STIH)

STIHL MS 241 C 2010-11

 Contents

1. Introduction and 6. Engine 34 8. M-Tronic 69

safety precautions 3
6.1 Muffler 34 8.1 Calibrating the
1.1 Introduction 3 6.2 Leak testing 35 control unit 69
1.2 Safety precautions 4 6.2.1 Preparations 35 8.2 Testing 70
6.2.2 Vacuum test 36 8.2.1 Test preparations 70
6.2.3 Pressure test 36 8.2.2 Connect the test lead 70
2. Specifications 5 6.3 Oil seals 37 8.2.3 Check screwed and
6.3.1 Ignition side 37 plug connections
2.1 Engine 5 6.3.2 Clutch side 37 as well as switch 70
2.2 Fuel system 5 6.4 Shroud 38 8.2.4 Checking the
2.3 Ignition system 5 6.5 Cylinder 39 solenoid valve 72
2.4 Chain lubrication 5 6.6 Crankshaft 41 8.2.5 Checking the start
2.5 Tightening torques 6 6.6.1 Ball bearing / detection function 73
crankcase 46 8.2.6 Checking the wiring
6.7 Piston 47 harness 74
3. Troubleshooting 8 6.8 Piston rings 49 8.3 Wiring harness 76
6.9 Decompression valve 50 8.4 Switchgear 76
3.1 Clutch 8 8.5 Troubleshooting,
3.2 Chain Drive, M-Tronic 80
Chain Brake, 7. Ignition system 51 8.5.1 Engine does not start 80
Chain Tensioner 9 8.5.2 Engine does not start
3.3 Chain lubrication 11 7.1 Ignition timing 51 in position } 81
3.4 Starter 12 7.2 Pre-separator 51 8.5.3 Engine speed drops
3.5 Ignition system 14 7.3 Control unit 51 under load
3.6 Carburetor 15 7.4 Spark test check – low power 82
3.7 Engine 18 control unit 54 8.5.4 Ignition –
7.5 Spark plug boot 55 no ignition spark 83
7.5.1 Ignition lead 56 8.5.5 Engine stops
4. Clutch 19 7.6 Flywheel 56 suddenly 84
7.7 Short circuit wire 57 8.5.6 Cut-off speed
4.1 Clutch drum 19 7.7.1 Contact test 57 not reached 85
4.2 Clutch 19 7.7.2 Removal and
installation 57
7.7.3 Ground wire 64 9. Rewind starter 86
5. Chain brake 20 7.7.4 Contact spring 64
7.8 Troubleshooting, 9.1 General 86
5.1 Checking operation of ignition system 66 9.2 Fan housing 86
chain brake 20 9.3 Pawls 87
5.2 Brake band 20 9.4 ErgoStart 88
5.3 Brake lever 21 9.5 Rope rotor 89
5.4 QuickStop Super 9.6 Starter rope /
brake lever 23 starter grip 89
5.4.1 Adjusting brake cable 25 9.7 Tensioning the rewind
5.4.2 Brake cable spring 90
Removal and 9.8 Replacing the rewind
installation 27 Spring 91
5.5 Cam lever 28
5.6 Pins 29
5.7 Chain tensioner 31
5.7.1 Quick chain
tensioner 31
5.7.2 Chain catcher 32
5.8 Bar mounting stud 32
5.9 Collar nut for chain
RA_741_00_01_01

sprocket cover 32

q
© ANDREAS STIHL AG & Co. KG, 2011

MS 241 C 1
Contents

10. Maintaining the 13. Fuel system 115 14. Heating 152
antivibration
elements 94 13.1 Air filter 115 14.1 Carburetor heating 152
13.2 Baffle 115 14.1.1 Check overall system 152
10.1 Antivibration element 13.3 Filter base 115 14.1.2 Check heating
on oil tank 94 13.4 Air guide shroud 117 element 152
10.2 Antivibration element 13.4.1 Air guide shroud, 14.1.3 Thermostatic switch 153
on fuel tank 94 versions with manual 14.2 Troubleshooting,
10.3 Antivibration element fuel pump 120 carburetor heating 154
on front handle 96 13.4.2 Air guide shroud 14.3 Handle heating
10.3.1 Antivibration element version with heating 123 systems 155
on handlebar, version 13.5 Carburetor 129 14.3.1 Troubleshooting 155
with heating 97 13.5.1 Leakage test 133 14.4 Heating switch 156
10.3.2 Stop buffer 98 13.6 Repairing the 14.5 Heating element
10.3.3 Filter base buffers 98 carburetor 133 in handle 158
10.4 Front handle 99 13.6.1 Metering diaphragm 134 14.6 Heating element in
10.4.1 Handlebar with 13.6.2 Inlet needle 135 front handle 159
heating 100 13.6.3 Pump diaphragm 135 14.7 Generator 160
13.6.4 Lead retainer 137 14.7.1 Troubleshooting chart,
13.6.5 Lever of the handle heating systems
11. Actuating levers 105 throttle shaft 137 and generator 162
13.6.6 Lever of the 14.7.2 Summary of test
11.1 Master Control lever 105 choke shaft 138 connections and test
11.1.1 Removal and 13.7 Carburetor values 164
installation 105 adjustment 138 14.8 Wiring harness 166
11.2 Throttle trigger / throttle 13.8 Carburetor bracket 138 14.9 Connecting leads
trigger interlock 106 13.9 Intake elbow 140 heating elements 167
11.3 Throttle trigger / 13.10 Tank vent 141
throttle trigger interlock / 13.10.1 Testing 141
QuickStop Super 107 13.10.2 Removal and 15. Special tools 170
11.3.1 Trigger switch installation 142
QuickStop Super 108 13.11 Fuel intake 143
11.3.2 Trigger interlock 13.11.1 Pickup body 143 16. Service
QuickStop Super 109 13.11.2 Fuel hose 143 accessories 172
11.4 Choke rod 110 13.11.3 Fuel hoses manual
11.5 Throttle rod 110 fuel pump 146
13.11.4 Manual fuel pump 148
13.11.5 Tank housing 149
12. Chain lubrication 112

12.1 Pickup body 112

12.2 Oil suction hose 112
12.3 Oil pump 112
12.4 Valve 114

2 MS 241 C
1. Introduction and safety precautions

1.1 Introduction The special tools mentioned in the

descriptions are listed in the chapter 1
"Special Servicing Tools" of this
This Service Manual contains 3
manual. The tools can be identified
detailed descriptions of all the
according to part number in the
typical repair and servicing
"STIHL Special Tools" manual. The
procedures for this machine.
manual lists all tools supplied by
2
STIHL.
Refer to the illustrated spare parts

2710RA320 TG
lists during all repair work. These
Symbols are included in the text and
lists show the installation position
pictures for greater clarity.
and order in which the individual
The meanings are as follows:
parts and modules should be Servicing and repairs are made
assembled. considerably easier if the machine
In the text:
is mounted on assembly stand (3)
Refer to the latest edition of the 5910 890 3101. For this purpose,
N Action to be taken as shown in
relevant spare parts list to check the secure the clamp (2)
the illustration above the text
part numbers of any spare parts 5910 850 1650 to the assembly
required. stand with two screws (1).
– Action to be taken that is not
A fault on the machine may be due shown in the illustration above
The screws must not protrude, as
to several causes. To help locate the text
they may damage the housings
the fault, consult the chapter on when clamping the machine,
"Troubleshooting" and the In the illustrations: depending on the machine.
"STIHL Service Training System"
for all functional groups. A Item pointer (short)

Refer to the "Technical Information" a Direction of

bulletins for engineering changes movement (long arrow)
which have been introduced since
publication of this Service Manual. @ 4.2 Reference to another
Technical information bulletins also chapter, in this case to
supplement the spare parts list and Chapter 4.2
Service Manual until an updated
Service Manuals and technical

2410RA000 TG
edition is issued.
information bulletins are intended
exclusively for the use of properly
equipped repair shops. They must
not be passed on to third parties. The machine is guided with the
collar screw through the upper hole
of the clamping rail and fastened
using nut M 8 (arrow).

The machine is fastened to the

mount on the clamping rail by the
screw head on the crankcase.

MS 241 C 3
Preparing to make repairs 1.2 Safety precautions The chapter "Tightening Torques"
lists all components of this machine
Before repair tasks or clamping on that must be tightened with the
Specific national safety regulations
the assembly stand, always remove specified tightening torques or
and the safety instructions in the
the chain sprocket cover, saw chain coated with thread-locking
instruction manual must be
and guide bar. adhesive. These specifications
observed if the machine has to be
must be observed throughout the
started up during maintenance or
Always use original STIHL Service Manual when tightening
repair work.
replacement parts. screws and nuts as well as other
They can be identified by the STIHL fasteners.
Gasoline is highly inflammable and
part number
can also be explosive under certain
the logo { conditions.
and the Fuel system – barbed connectors
STIHL parts symbol K
Do not bring any fire, flame, spark or
The symbol may appear alone on other source of heat near the fuel.
Pull or push the fuel hoses, by hand
small parts. All work with fuel must be performed
whenever possible, in the direction
of the connector in order to ensure
outdoors only. Spilled fuel must be
leakproofness of the fuel system.
wiped away immediately.
Storage or disposal of oil and fuel
Avoid damaging the barbed
Test for leakage after all work on the
Collect fuel or lubricating oil in fuel system and engine.
connectors
a clean container and dispose of it – sharp-edged pliers, screwdrivers,
in accordance with environmental etc., may not be used.
Exercise extreme caution while
regulations. Also, do not cut open fuel hoses
carrying out maintenance and repair
with a knife or similar aids.
work on the ignition system. The
high voltages which occur can
Plug connections on electrical Do not reuse fuel hoses after
cause serious or fatal accidents.
leads disassembly, but instead always
replace them with new hoses
Suitable gloves must be worn
– fuel hoses can be overstretched
without fail if parts are heated for
when being detached.
assembly/disassembly purposes.
a Mount new fuel hoses dry or using
Improper handling may result in
STIHL press fluid, b 16.
burns and other serious injuries.
Other press fluids are not permitted
Always replace damaged parts.
and may lead to fuel hose damage.
Check dismantled parts for wear
5902RA299 TG

and damage before installation,

When using STIHL press fluid,
replace if necessary.
apply press fluid to the ends of the
hose and the connectors and press
The insulating tube must be Only use the machine with the
the new hoses onto the barbed
oriented so that it is centered over shroud mounted – otherwise the
connectors, b 16.
the plug connection and completely rotating fan wheel poses a risk of
enclose the plug connection injury and there is a risk of engine
– danger of short-circuiting. damage due to overheating.

The plug connection is completely

plugged together when it has a total
length of a = max. 30 mm.

4 MS 241 C
2. Specifications

2.1 Engine

MS 241 C

Displacement: 42.6 cm3

Bore: 42.5 mm
Stroke: 30.0 mm
Engine power to ISO 7293: 2.2 kW (3.0 HP)
at 10000 rpm
Max. permissible engine speed
(with bar and chain): 14000 rpm
Idle speed: 2800 rpm
Clutch: Centrifugal clutch without
linings
Clutch engages at: 3500 rpm
Crankcase leakage test
at gauge pressure: pü = 0.5 bar
under vacuum pu = 0.5 bar

2.2 Fuel system

Carburetor leakage test at
gauge pressure: pü = 0.8 bar
Operation of tank vent at
gauge pressure: pü = 0.5 bar
Fuel: as specified in instruction
manual

2.3 Ignition system

Air gap between control unit
and fanwheel: 0.30 (+ 0.05/- 0.10) mm
Spark plug (suppressed): NGK CMR 6 H
Electrode gap: 0.5 mm

2.4 Chain lubrication

Speed-controlled oil pump with reciprocating piston and
manual oil flow control

Oil flow settings:

min: 4.0 (+/- 2.0) cm3/min

at 7000 rpm

max: 8.0 (+/- 3.0) cm3/min

at 7000 rpm

MS 241 C 5
2.5 Tightening torques

DG and P screws are fitted in plastic and light alloy metal parts. These screws form a permanent thread when
they are installed for the first time. The material is permanently deformed. Screws can be removed and installed
as often as necessary without impairing the strength of the screwed assembly, provided that the specified
tightening torque is observed.
For this reason it is essential to use a torque wrench.

Fastener Thread size For component Tightening Comment

torque
Nm

Screw P 4x12 Cover plate / fan housing 2.0

Screw P 4x10 Cover / tank housing 1.0
Screw D 4x12 Cover / chain tensioner / crankcase 2.5 2), 4)
Screw M 5x16 Antivibration element / crankcase 8.0 2), 4)
Screw P 5x34 Antivibration element / tank housing 4.0
Screw D 4x12 Brake band / crankcase 3.0 2), 4)
Screw P 4x10 Brake cable support / tank housing 1.0 Q
Stud M 5x18 Stud 7.0 2), 3)
Stud M8 Bar mounting stud 23.0 1)
Stud M8 Bar mounting stud 23.0 1), B
Stud D 8x18 Bar mounting stud (repair solution) 16.0
Screw D 4x12 Cover, chain brake / crankcase 3.0 2), 4)
M 10x1 Decompression valve 14.0
Nut M5 Filter base / baffle / carburetor 3.5
Screw M 4x12 Generator / crankcase 3.0 3), VW
Screw P 6x25 Handlebar / locking screw 8.0 VW
Screw P 6x26.5 Handlebar / tank housing right 6.0
Screw P 6x30 Handlebar / tank housing right 6.0 2), 4), VW
Screw M 5x16 Handlebar / tank housing bottom 5.0 2), 3)
Screw M 5x12 Handlebar / tank housing bottom 8.0 3), VW
Screw M 5x16 Handlebar / plugs antivibration springs 10.0 2), 3), VW
Screw M 5x20 Hand guard / fan housing / crankcase 6.0 3)
Screw P 6x30 Chain catcher / crankcase / bearing plugs 6.0
Nut M5 Spiked bumper / crankcase / upper lock nut 8.0
Screw M 5x10 Spiked bumper / top of crankcase 8.0 2), 3)
Screw M 5x16 Spiked bumper / bottom of crankcase 8.0 2), 3)
Screw D 4x12 Manifold / cylinder 4.0 2), 4)
Screw M 5x20 Crankcase drive side / fan side 10.0 2), 4)
Screw M 5x16 Bearing plugs / cylinder 10.0 2), 3)
Screw M 5x16 Fan housing / crankcase 6.0 2), 4)
Screw D 4x12 Air guide shroud / crankcase 4.0 2), 4)

6 MS 241 C
Fastener Thread size For component Tightening Comment
torque
Nm

Carrier M 12x1 L Crankshaft carrier 50.0

Screw D 4x12 Oil pump / crankcase 4.0 2), 4)
Screw M 5x16 Muffler / crankcase 10.0 2), 3)
Screw M 5x16 Muffler / cylinder 10.0 2), 3)
Nut M 8x1 Flywheel / crankshaft 28.0 5)
Nut M 12x0.75 Switch 2.0
Screw P 4x10 Support 1.0
Screw D 4x12 Pre-separator / crankcase 4.0 2), 4)
M 10x1 Spark plug / cylinder 12.0
Screw D 4x20 Control unit / cylinder 4.5 2), 4)
Screw M 5x20 Cylinder / crankcase 1st stage 4.0 2), 4)
Screw M 5x20 Cylinder / crankcase 2nd stage 10.0 2), 4)

Remarks:

1) Loctite 242 or 243 medium strength

2) Screws with locking serration
3) Microencapsulated screws
4) Screws with easy-slide coating
5) Connection between crankshaft and flywheel must be degreased and oil-free
Q) QuickStop Super
B) Quick chain tensioner
VW) Heating

When inserting DG and P screws into an existing screw thread:

Insert the DG or P screw in the hole and turn counterclockwise until it gently drops into the hole in axial direction.
Tighten the screw clockwise to the specified torque.

This procedure ensures that the screw engages properly in the existing thread and does not form a new thread
and weaken the assembly.

Coat micro-encapsulated screws with Loctite 242 or 243 medium strength before refitting them.

Screwdriver speed when used in plastic material: max. 500 rpm for DG and P-type screws.
Do not use an impact wrench to release or tighten screw connections.

Screws with and without locking serration must not be confused.

MS 241 C 7
3. Troubleshooting

3.1 Clutch

Problem Cause Remedy

Saw chain becomes stuck under Clutch shoes badly worn Install new clutch
full load

Clutch drum badly worn Install new clutch drum

Saw chain rotates at idle speed Idle speed too high Check M-Tronic

Tension springs of the clutch shoes Replace tension springs, replace

are stretched clutch if necessary

Tension springs of the clutch shoes Replace tension springs

are broken

Loud noises Tension springs stretched Replace all tension springs

Needle cage damaged Replace needle cage

Clutch shoe retainer broken Examine retainer, replace if

necessary

Clutch shoes and carrier worn Install new clutch

8 MS 241 C
3.2 Chain Drive, Chain Brake, Chain Tensioner

Problem Cause Remedy

Chain sprocket wears rapidly Chain not properly tensioned Tension chain as specified

Wrong chain pitch Fit chain of correct pitch

Insufficient chain lubrication Check chain lubrication

Saw chain becomes stuck under Clutch shoes badly worn Install new clutch
full load

Clutch drum badly worn Install new clutch drum

Brake band stuck Check freedom of movement and

function of brake band

Saw chain rotates at idle speed Idle speed too high Check M-Tronic

Tension springs of the clutch shoes Replace tension springs, replace

are stretched clutch if necessary

Tension springs of the clutch shoes Replace tension springs

are broken

Saw chain does not stop Brake spring stretched or broken Fit new brake spring
immediately when brake is
activated

Brake band stretched, worn or Fit new brake band

broken

Clutch drum worn Install new clutch drum

MS 241 C 9
Problem Cause Remedy

QuickStop Super Brake cable stretched Adjust brake cable

Coasting brake is not released
although trigger interlock is pressed

Brake cable unhooked or broken Reattach or replace brake cable

QuickStop Super Excessive play on trigger interlock Adjust brake cable

Brake band is not released
although trigger interlock is pressed

QuickStop Super Brake cable overstretched Adjust brake cable

Coasting brake does not brake
properly – trigger interlock not
pressed

Sleeve of the brake cable not Push the sleeve into the adjusting
seated completely in adjusting screw as far as it will go and adjust
screw brake cable

10 MS 241 C
3.3 Chain lubrication

In the event of trouble with the

chain lubrication system, check and .
rectify other sources of faults
before disassembling the oil pump.

Problem Cause Remedy

Chain receives no oil Oil inlet hole in guide bar is blocked Clean oil inlet hole

Intake hose or pick-up body Fit new intake hose and pick-up
clogged or intake hose ruptured body

Valve in oil tank blocked Clean or replace valve

Worm worn Replace worm

Oil pump damaged or worn Install new oil pump

Machine looses chain oil Oil pump damaged or worn Install new oil pump

Oil intake hose connection Fit new oil intake hose

damaged

Crankcase cracked Check crankcase halves and

replace damaged crankcase halves

Oil pump delivers insufficient oil Oil pump damaged or worn Install new oil pump

Worm carrier is loose Replace worm

MS 241 C 11
3.4 Starter

Problem Cause Remedy

Starter rope broken Rope pulled out too vigorously as Replace starter rope
far as stop or over edge, i.e. not
vertically

Normal wear Replace starter rope

Starter rope does not rewind Heavy fouling or rust on rewind Clean or replace rewind spring
spring

Spring insufficiently tensioned Check rewind spring and increase

tension

Rewind spring broken Replace rewind spring

Starter rope cannot be pulled out Rewind spring overtensioned Check rewind spring and reduce
far enough tension

Starter rope can be pulled out Guide peg on pawls or pawls Replace pawls
almost without themselves are worn
resistance (crankshaft does not
turn)

Spring clip fatigued Replace spring clip

Spring clip improperly installed Install spring clip properly

...Versions with ErgoStart Guide peg on pawls or pawls Replace pawls

themselves are worn

Torsion spring on flywheel are Clean mounts on the pawls,

fatigued, pawls are worn or sticking replace pawls and torsion springs if
necessary

Lugs on carrier are worn Replace carrier

Anchor loop in spring housing not Hook anchor loop to carrier

hooked onto carrier

Starter rope is difficult to pull – Spring in spring housing is fatigued Replace spring housing
versions with ErgoStart

12 MS 241 C
Problem Cause Remedy

Starter rope is difficult to pull or Starter mechanism is very dirty Thoroughly clean complete starter
rewinds very slowly mechanism

At very low outside temperatures: Coat rewind spring with a little

Lubricant oil on the rewind spring standard solvent-based degreasant
becomes viscous (spring winding (containing no chlorinated or
stick together) or moisture has halogenated hydrocarbons), then
penetrated the rewind spring pull rope carefully several times
(spring windings are frozen) until normal action is restored

MS 241 C 13
3.5 Ignition system

Problem Cause Remedy

Engine runs roughly, misfires, Spark plug boot is loose Press boot firmly onto spark plug
temporary loss of power and fit new spring if necessary

Spark plug sooted, smeared with oil Clean the spark plug or replace if
necessary
In the event of repeated sooting,
check air filter

Fuel/oil mixture Use a fuel mixture with the correct

– contains too much oil mixing ratio

Wrong air gap between control unit Set the correct air gap
and flywheel

Flywheel is cracked Install new flywheel

or has other damage or pole shoes
have turned blue

Incorrect ignition timing, flywheel Install new flywheel

out of adjustment
– Key in flywheel has sheared off

Weak magnetization in flywheel Install new flywheel

Irregular spark Check operation of switch shaft/

contact spring and control unit
Damaged insulation or interruption
in ignition lead or short circuit wire.
Check ignition lead/control unit,
replace control unit if necessary.
Check operation of spark plug,
clean spark plug and replace if
necessary. Check M-Tronic

14 MS 241 C
3.6 Carburetor

Problem Cause Remedy

Carburetor floods; engine stalls Inlet needle not sealing Remove and clean inlet needle or
– Foreign matter in valve seat or clean carburetor
cone

Inlet needle worn Replace inlet needle

Inlet control lever sticking on Examine control lever, replace if

spindle necessary

Helical spring not located on nipple Remove the inlet control lever and
of inlet control lever refit it correctly

Perforated disc on diaphragm is Replace metering diaphragm

deformed and presses constantly
against the inlet control lever

Metering diaphragm is deformed Replace metering diaphragm

Poor acceleration Carburetor setting too lean Check M-Tronic

Carburetor setting too rich Check M-Tronic

Inlet needle sticking to valve seat Remove inlet needle, clean and
refit

Diaphragm gasket leaking Replace diaphragm gasket

Metering diaphragm damaged or Replace metering diaphragm

shrunk

Tank vent faulty Replace tank vent

Leak in fuel line between tank and Seal connections or replace line
carburetor

MS 241 C 15
Problem Cause Remedy

Engine will not idle, idle speed too Throttle shutter is not closed Examine carburetor and throttle
high properly when the throttle trigger is rod, replace if necessary
not pressed

Oil seals or crankcase leaking Seal oil seals or crankcase, replace

if necessary

Throttle shutter does not close Replace carburetor

Engine stops when idling Idle jet bores Clean the carburetor
or ports blocked

Idle jet too rich or Check M-Tronic

too lean

Tank vent faulty Replace tank vent

Leak in fuel line between tank and Seal connections or replace line
carburetor

Saw chain rotates at idle speed Idle speed too high Check M-Tronic

Clutch springs stretched or fatigued Replace tension springs, replace

clutch if necessary

Anchor loops of the clutch spring Replace tension springs

hooks are broken

16 MS 241 C
Problem Cause Remedy

Engine speed drops quickly under Air filter dirty Clean air filter, replace if necessary
load – low power

Throttle shutter not opened fully Check throttle rod

Tank vent faulty Replace tank vent

Fuel pick-up body dirty Replace pickup body

Fuel strainer dirty Clean fuel strainer in carburetor,

replace if necessary

Leak in fuel line between tank and Seal connections or replace line
carburetor

Carburetor setting too lean Check M-Tronic

Main jet bores or ports blocked Clean the carburetor

Pump diaphragm damaged or Replace pump diaphragm

fatigued

Incorrect ignition timing, flywheel Install new flywheel

out of adjustment
– Key in flywheel has sheared off

Engine runs extremely rich, lacks Choke shutter does not open Examine the carburetor and starter
power and has very low final speed shaft and repair or replace if
necessary

Carburetor setting too rich Check M-Tronic

MS 241 C 17
3.7 Engine

Always check and, if necessary,

repair the following parts before
looking for faults on the engine:

- Air filter,
- Fuel system,
- Carburetor,
- Ignition system

Problem Cause Remedy

Engine does not start easily, stalls Oil seals in engine defective Replace oil seals
at idle speed but operates normally
at full throttle

Crankcase leaking or Replace damaged crankcase

damaged (cracks) halves

Intake manifold damaged/ hole is Clean hole or replace intake

plugged manifold

Engine does not deliver full power Piston rings worn or broken Replace piston rings
or runs erratically

Muffler / spark arresting screen Clean muffler (inlet and outlet

carbonized openings), replace spark arresting
screen, replace muffler if necessary

Air filter dirty Clean or replace air filter

Fuel line kinked or cracked Replace fuel line and ensure that is
installed without kinking

Intake manifold damaged / hole is Clean hole or replace intake

plugged manifold

Engine is overheated Insufficient cylinder cooling. Air Thoroughly clean all cooling air
inlets in fan housing blocked or openings and the cylinder fins
cooling fins on cylinder very dirty

Air intake in fan housing is fouled Clean air intake on fan housing

18 MS 241 C
4. Clutch

4.1 Clutch drum

1
– Clutch drum removal and
installation, see Instruction
Manual
1
– Remove needle cage

2410RA001 TG

2410RA004 TG
– Clean needle cage and
crankshaft stub, b 16

: Remove the spark plug boot (1) : Unscrew the clutch (1) with
– Grease needle cage and
hexagon (arrow) – left-hand
crankshaft stub, b 16
– Unscrew spark plug thread

Installation
1
1
TOP

1
100%
5902RA018 TG

2410RA002 TG
80% ! 2

2410RA005 TG
– Examine the clutch drum (1) for
signs of wear : Orient the locking strip (1)
0000 893 5904 so that the flat
side of the metallic attachment Slide washer (1) into place so that
The remaining thickness must be the word "TOP" is visible.
faces the piston and insert it in
measured if there are distinct signs
the cylinder
of wear on the inside diameter of the : Fit the clutch (2) on the
clutch drum (1). The clutch drum crankshaft stub so that the raised
must be replaced if the remaining hexagon (arrow) can be seen
thickness is less than approx. 80 %
of the original thickness.
1
: Screw on and tighten the
clutch (2) – left-handed thread
– Install the clutch drum

– Pull the locking strip out of the

cylinder
4.2 Clutch
2410RA003 TG

– Reassemble remaining parts in

– Troubleshooting, b 3.1 reverse order

– Removing the clutch drum,

b 4.1 : Locking strip (1) 0000 893 5904
must rest against the cylinder
wall (arrow) and the flat side of
– Remove shroud, b 6.4 the metal attachment must rest
against the piston head
– Position as shown

MS 241 C 19
5. Chain brake

5.1 Checking operation of All versions : Ease brake band (2) out of
chain brake guide (arrow)
The braking time is in order if
deceleration of the saw chain is – Remove brake band, taking care
The chain brake is one of the most
imperceptible to the eye (less than 1 not to overextend it
important safety devices on the
second).
chain saw. Its efficiency is
measured in terms of the chain – Release the chain brake
If the chain brake does not operate
braking time, i.e., the time that
properly, refer to the
elapses between activating the
troubleshooting chart, b 3.2.
brake and the saw chain coming to
a complete standstill.
5.2 Brake band
Fouling (particularly with chain oil,
chips, fine particles of abrasion, 2
etc.) and smoothing of the friction – Remove the clutch drum, b 4.1
surfaces of the brake band and
clutch drum impair the coefficient of – Troubleshooting, b 3.2
friction. This in turn extends the

5902RA024 TG
braking time. A fatigued or stretched
brake spring has the same negative 1
effect. 2 1
: Turn brake band (1) slightly aside
– Starting the engine and disconnect it from the brake
lever (2)
– With the chain brake
activated (locked), open the
throttle wide for a brief
2410RA006 TG

period (max. 3 seconds) – the

chain must not rotate
1
– With the chain brake released,
open the throttle wide and : Remove screws (1)
activate the brake manually – the
chain must come to an abrupt : Remove the cover (2)

219RA049 TG
stop
– Block chain brake
Versions with QuickStop Super
Install a new brake band if there are
When the trigger interlock is noticeable signs of wear on large
pressed, the clutch drum must areas on the inside diameter and/or
rotate freely. parts of the outside (arrows) and its
remaining thickness is less than
With the coasting brake released, 2 < 0.6 mm.
open the throttle wide and release
the trigger interlock in the rear
handle – the saw chain must come
2410RA007 TG

to an abrupt stop

: Unscrew screw (1) on the bottom

of the machine

20 MS 241 C
Installation 5.3 Brake lever

– Troubleshooting, b 3.2
1
– Remove shroud, b 6.4
2
– Remove fan housing, b 9.2

2410RA012 TG
2 – Remove brake band, b 5.2

1 2410RA009 TG
: Push brake band (1) fully home in
the mount (arrow)
– Release the chain brake
: Screw in and tighten screw (2) on
: Attach brake band (1) to brake the bottom of the machine
lever (2) sideways and turn it
towards its mount

1 2

2410RA014 TG
1 1

– Block chain brake

2410RA013 TG The brake spring is now relaxed.

2 : Use the assembly tool

2410RA010 TG

1117 890 0900 to unhook the

brake spring (1) at the anchor
: Insert cover (1)
pin (arrow)
: Insert brake cable (1) in : Insert and tighten down the
guide (arrow) – Unhook and remove the brake
screws (2)
spring at the brake lever
– Block chain brake – Install the clutch drum, b 4.1

When the chain brake is released,

the clutch drum must rotate freely.
1
– Carry out additional function
tests, b 5.1

– Reassemble remaining parts in

reverse order
2410RA011 TG

: Guide brake band (1) over

studs (arrows) and press it into
the mount

MS 241 C 21
 – Examine pins and replace if
necessary, b 5.6 2
1
– Check cam on hand guard,
replace hand guard if necessary
1

2410RA015 TG Installation

2410RA020 TG
– Clean pins and disassembled
parts, b 16
: Push out circlip (1) : Slightly lift up bearing eye of the
– Grease pins, b 16 hand guard (1) and brake
lever (2) and guide the parts over
the anchor pins (arrows)
2
1 1 2
2410RA016 TG

2410RA018 TG

2410RA021 TG
: Draw hand guard (1) and brake
lever (2) off the anchor : Position brake lever (2) so that
pins (arrows) simultaneously mount for brake spring (arrow) is
at the top : Turn cam lever (1) slightly aside
– Take out hand guard and brake until cam of hand guard (arrow)
lever : Slide brake lever (2) into recess slides past
in hand guard (1) until the holes
– Examine cam lever and replace if are lined up – Press bearing eye of hand guard
necessary, b 5.5 and brake lever onto the anchor
pins

2
1 2 1

1
2410RA019 TG
2410RA017 TG

2410RA022 TG

: Slide hand guard (1) with brake

: Pull brake lever (2) out of hand lever (2) across the machine until
guard (1) it rests against the anchor : Push circlip (1) into place
pins (arrows)

22 MS 241 C
 – Unhook and remove the brake
1 spring at the brake lever

5902RA040 TG

2410RA024 TG
1

The turns of the brake spring must : Use the assembly tool (2)

2410RA026 TG
be tightly spaced when not installed; 1117 890 0900 to attach the
use a new brake spring if necessary. brake spring (1) to the anchor
pin (arrow)
– Position the protective tube so : Unhook brake spring (1) from
that it starts after the – Grease brake lever, cam lever anchor pin (arrow)
second turn (arrow) and hand guard motion link,
b 16 : Unhook and remove the brake
– The pin for the brake spring must spring (1) at the brake lever
be replaced if it shows signs of – Reassemble remaining parts in
wear at the groove, b 5.6 reverse order

5.4 QuickStop Super brake 1

lever
2
– Troubleshooting, b 3.2

2410RA027 TG
– Remove shroud, b 6.4
2410RA023 TG

– Remove fan housing, b 9.2

1 : Draw hand guard (1) and brake
– Remove brake band, b 5.2
lever (2) off the anchor
: Hook brake spring (1) into brake pins (arrows) simultaneously
lever (arrow)
1 – Take out hand guard and brake
lever
2410RA025 TG

– Block chain brake

The brake spring is now relaxed.

: Use the assembly tool

1117 890 0900 to unhook the
brake spring (1) at the anchor
pin (arrow)

MS 241 C 23
 Installation
1
– Clean pins and disassembled 1
parts, b 16
2
– Grease pins, b 16

2410RA028 TG

2410RA032 TG
2

: Disconnect brake cable (1) : Slide hand guard (1) with brake
lever (2) across the machine until
it rests against the anchor
1 pins (arrows)
2

2410RA030 TG
1
: Position brake lever (2) so that
mount for brake spring (arrow) is
at the top 2
2410RA029 TG

1
: Slide brake lever (2) into recess
in hand guard (1) until the holes

2410RA033 TG
: Pull brake lever (2) out of hand are lined up
guard (1)

– Examine cam lever and replace if : Slightly lift up bearing eye of the
necessary, b 5.5
1 hand guard (1) and brake
lever (2)and guide the parts over
the anchor pins (arrows)
– Examine pins and replace if
necessary, b 5.6

– Check cam on hand guard,

2410RA031 TG

replace hand guard if necessary

: Attach brake cable (1) to

hole (arrow) in brake lever

24 MS 241 C
 : Attach brake spring (1) to anchor
pin (2) 1

2410RA034 TG

2410RA025 TG
1

: Turn cam lever (1) aside until : Use the assembly tool

5902RA040 TG
cam of hand guard (arrow) slides 1117 890 0900 to hook the brake
past spring (1) onto the anchor
pin (arrow)
– Press bearing eye of hand guard The turns of the brake spring must
and brake lever onto the anchor be tightly spaced when not installed; – Grease brake lever, cam lever
pins use a new brake spring if necessary. and hand guard motion link,
b 16
– Position the protective tube so
that it starts after the – Adjust brake cable, b 5.4.1
1 second turn (arrow)
– Reassemble remaining parts in
– The pin for the brake spring must reverse order
be replaced if it shows signs of
wear at the groove, b 5.6
5.4.1 Adjusting brake cable
2410RA035 TG

1 If the coasting brake does not

operate properly although the brake
band is intact, it may be necessary
: Check seat of the sleeve (1) at to adjust the brake cable.
the brake cable, push completely
into the hole in the – Troubleshooting, b 3.2
housing (arrow) if necessary
2410RA037 TG

– Check condition and play

2 – Remove chain brake cover,

b 5.2
: Hook brake spring (1) onto brake
lever (arrow)
When the trigger interlock is not
1 pressed, the brake cable must
be without tension.
2410RA036 TG

: Hook brake spring (1) into the

brake lever so that the opening of
the anchor loop (arrow) is visible

MS 241 C 25
 Adjust brake cable : Screw in adjusting screw (2)
– Play increases

: Unscrew adjusting screw (2)

1 – Play decreases
1
: Once play is adjusted correctly,
2410RA038 TG
2 tighten clamping screw (3)

2410RA039 TG
– Press and hold the trigger
interlock down completely
: Remove screw (1)
Brake band (1) must rest against
the crankcase (arrows) without play : Lower tank housing (2) 1
and the clutch drum must rotate
freely.

2410RA038 TG
– Release trigger interlock 1

– Press and hold the trigger

interlock down completely
1
a Brake band (1) must rest against
the crankcase (arrows) without play
2310RA050 TG

and the clutch drum must rotate

freely.

– Reassemble remaining parts in

0001RA456 TG

: Loosen clamping screw (1) on

the support for the brake cable reverse order

: Press trigger interlock (1) gently

to check the play
1
– The play must not exceed the
mark (a) 2
3
Play: is equal to the distance
traveled by the trigger interlock (1)
2410RA556 TG

without causing the brake lever to

move at the same time.

Play is necessary to ensure trouble

The sleeve (1) must be seated on
free functioning of the coasting
the adjusting screw (2) as far as it
brake.
will go.
– Troubleshooting, b 3.2
: Position open-end wrench SW 6
on the adjusting screw (2) and
adjust play

26 MS 241 C
5.4.2 Brake cable : Push hook (1) through the
Removal and installation 1 support (2) with a gentle twisting
motion
– Unhook brake spring, b 5.4

– Remove QuickStop Super 2 1

throttle trigger, b 11.3

2310RA053 TG
– Remove QuickStop Super trigger
switch, b 11.3.1 2

: Examine brake cable (1) and

support (2), replace if necessary

2310RA056 TG
1
Dismantle brake cable and
support : Turn adjusting screw (1) until the
distance between the hexagon of
the adjusting screw and the
2 holder is 2 mm
2410RA040 TG

1
: Screw in the clamping screw (2)
and tighten
: Pull brake cable (1) out slightly
and disconnect it
2310RA054 TG
4
– Loosen tank housing and lower it, 3 4
b 13.11.2
: Unscrew clamping screw (1) and
2
– Do not overextend fuel hose adjusting screw (2) 3
: Turn hook (3) so that the angled 1

2410RA042 TG
2 part is at the opening (arrow) and
twist it out of the support (4)

: Guide the brake cable (1) over

Installation fuel hose (3) or, in versions with
1
manual fuel pump, over the fuel
hose (3) and fuel return line (2)
2
2410RA041 TG

: Push brake cable (1) with short

hook (4) in front through the
hole (arrow) in the crankcase
: Remove screw (1)

: Remove support (2) with brake

2310RA055 TG

cable
1

: Turn hook (1) so that it runs along

the support (2) and push it into
the hole (arrow)

MS 241 C 27
 – Reassemble remaining parts in
1 reverse order
1
– Adjust brake cable and check
2 operation, b 5.4.1

2410RA043 TG 5.5 Cam lever

2410RA046 TG
The cam lever defines the engaged
position of the hand guard.
: Push brake cable (1) with sleeve When raising the tank housing,
into the hole in the make certain that the sleeve (1) is – Remove brake lever, b 5.3,
housing (arrow) as far as it will go pushed completely into the QuickStop Super, b 5.4
adjusting screw (2) – incomplete
insertion of the sleeve changes the
setting of the brake cable.
1 2 2
– Check position of the fuel hose
and correct it if necessary,
b 13.11.2 1

– Check position of the fuel return

line and correct it if necessary,
2410RA044 TG

2410RA048 TG
b 13.11.3
3
– Raise and fasten the
tank housing, b 13.11.2
: Hook brake cable (1) into : Unhook the brake spring (1) from
hole (arrow) in brake lever (2) the anchor pin (2)

– Unhook and remove the brake

2 spring (1) at the cam lever

: Push out circlip (3)

1
1 – Remove cam lever
2410RA047 TG
2410RA045 TG

: Insert brake cable (1) in

guide (arrow)
: Press brake cable holder with the
pin (1) through the opening and
into the mount (arrow) – Install QuickStop Super trigger
switch, b 11.3.1
: Screw in the screw (2) and
tighten it – Install QuickStop Super throttle
trigger, b 11.3

28 MS 241 C
 5.6 Pins

The pins ensure that the springs are

securely mounted. They must
2 therefore be replaced when worn,
otherwise the springs may pop out.

1 The pins must be driven in square.

2410RA051 TG
2410RA049 TG
1 For reasons of simplicity, the parts
connected to the pins have already
: Examine cam lever (1) and brake : Push circlip (1) into place been removed in the following
spring (2) and replace if illustrations.
necessary

: Check condition of cam 2 2 3 1 6

guide (arrow) and replace hand
guard if necessary 1

– Examine all pins and replace if

necessary,
b 5.6

2410RA052 TG

2410RA053 TG
4 5
Installation
: Hook brake spring (1) into the : Remove pins (1) through (6)
– Clean pins and disassembled brake lever so that the opening of
parts, b 16 the anchor loop (arrow) is visible
Item 6 is present only in the version
– Grease pins, b 16 with QuickStop Super.
: Hook brake spring (1) onto
pin (2)

– Grease cam lever, b 16

3
The cam lever is not yet tensioned –
the spring may become detached
again.
1
– Reassemble remaining parts in
2 reverse order
2410RA050 TG

: Orient cam lever (1) so that the

cam (arrow) faces the pin (3)

: Slide cam lever (1) onto anchor

pin (2)

MS 241 C 29
Installation Machines with QuickStop Super
a

1
2
b

0001RA061 TG
5
2410RA054 TG

2410RA058 TG
: Pin (1) a = approx. 2.9...3.3 mm 6
Pin (2) b = approx. 4.3...4.7 mm
– Coat the knurled area of the new : Drive in anchor pins (5) and (6) in
pin with Loctite before fitting the accordance with the following
pin, b 16 information

: The pin must be inserted in the

hole (arrow) so that the knurling
on the pin engages the knurled a
profile
3
Turn the pin back and forth slightly 6
2410RA056 TG

until it fits.
4 5
b
The pins must be driven in square.

2410RA059 TG
: Drive in anchor pins (3), (4)
and (5) in accordance with the 5
following information
: Pin (5) b = approx. 5.1...5.3 mm
Pin (6) a = approx. 2.9...3.3 mm

4 a – Reassemble remaining parts in

reverse order
3
2410RA055 TG

5 – Grease brake and cam levers,

b 16
2 1 c
2410RA057 TG

: Drive in pins (1) and (2) in

accordance with the following
information b
: Pin (3) a = approx. 8.9...9.1 mm
Pin (4) b = approx. 4.6...4.8 mm
Pin (5) c = approx. 5.1...5.3 mm

30 MS 241 C
5.7 Chain tensioner 5.7.1 Quick chain
tensioner
– Troubleshooting, b 3.2 The quick chain tensioner is built
into the chain sprocket cover.
1

2410RA063 TG
2
2
3
2410RA060 TG
– Fold out wing nut (1)

: Push wing nut (1) into the

2410RA544 TG
1 opening thin side (arrow) first,
1 then press it in until it snaps into
place
: Turn the spur gear (2) clockwise
until the tensioner slide (1) : Unscrew screw (1) and remove
makes contact on the right and side plate (2), remove Loctite
the screw (3) is revealed residue if necessary
1
: Remove screw (3) – Examine side plate, replace if
necessary
: Remove spur gear (2) and 2
tensioner slide (1) – Coat screw with Loctite before
insertion, b 16

2410RA064 TG
– Install parts in reverse order
2 2 4
: Remove the screw (arrow)

: Remove cover plate (1) and

adjusting wheel (2)
1
2410RA061 TG

When installing the adjusting wheel,

1 3 make certain that the teeth face the
cover plate
2410RA062 TG

: Examine the cover (1), spur gear

– Reassemble the parts in reverse
kit (2), tensioner slide (3) and
thrust pad (4) and replace if order
necessary : Carefully pry out wing nut (1) at
the side (arrow)
– Clean all disassembled parts,
b 16 – Check wing nut (1) and replace if
necessary
– Coat the threads and gear
wheels with STIHL multi-purpose
grease, b 16

– Reassemble parts in reverse

order

MS 241 C 31
5.7.2 Chain catcher – Reassemble remaining parts in
reverse order
– Remove the chain sprocket cover

5.9 Collar nut for chain

sprocket cover

2410RA067 TG
This chain sprocket cover can only
be used on the MS 241.
It cannot be retrofitted to other
1 models. The length and shape of
the stud must be appropriate for the – Flip over the chain sprocket cover
chain sprocket cover with captive and clamp the assembly tool into
2410RA300 TG

nut. a vise by the hexagon

2 The special tool stud : Drill out the collar nut with an
5910 893 9600 is available for 11 mm diameter drill bit – the
: Remove screw (1) and pull out replacing the nut. base in the chain sprocket cover
chain catcher (2) under the
must not be drilled out
bumper strip

– Reassemble parts in reverse 2 1 – Pull out the collar nut

order
– Unscrew the assembly tool from
the collar nut
5.8 Bar mounting stud
2410RA066 TG

– Remove the chain sprocket cover

2 – Remove the chain sprocket cover

: Screw the assembly tool (1)

5910 893 9600 with the short
1 stud into the collar nut (2) as far
as it will go
2410RA065 TG

: Push stud driver (1)

5910 893 0501 onto the stud (2)
as far as it will go and unscrew
counterclockwise

– Coat stud with Loctite, screw in

and tighten, b 16

32 MS 241 C
Installation

2410RA068 TG

: Push in new collar nut (1)

1
2410RA069 TG

– Hold the hexagon of the collar nut

in place

: Screw the assembly tool (1)

5910 893 9600 with the long stud
into the opposite side of the collar
nut as far as it will go

Now the new collar nut has been

flanged and secured in the chain
sprocket cover.

– Reassemble remaining parts in

reverse order

MS 241 C 33
6. Engine

6.1 Muffler – Remove and install spark

arresting screen, if present, see 2
Check and if necessary repair the
fuel supply, carburetor, air filter and Instruction Manual
1
ignition system before looking for
faults on the engine. 2
Installation
– Troubleshooting, b 3.7
– Cover exhaust bore and remove

2410RA071 TG
– Remove shroud, b 6.4 any fouling on the cylinder and
exhaust bore 3 3
To keep dirt particles from entering
the cylinder, move piston to top : Carefully fit the muffler (1)
dead center before removing the
muffler. : Fit screws (2) and check that
gasket is correctly positioned

1 1 : Insert screws (3) – do not tighten

: First tighten screws (2), then

2410RA072 TG
tighten screws (3)

– Press in new stoppers evenly and

straight around the
: Examine and clean the mating
2410RA070 TG

circumference with a blunt tool –

surfaces (arrows), remove any
do not insert them on a slant or
gasket residues if necessary –
damage them
there must not be any gasket
residues or dirt particles in the
: Pry out the stoppers (1) around
exhaust bore
the circumference at the
markings
– Do not reuse dismantled Parts with damaged mating
stoppers surfaces must be replaced.

1
3

1
2410RA073 TG
2410RA071 TG

2 2 1

: Orient the exhaust gasket (1) so

: Remove screws (1) and (2)
that the tabs (arrows) face
towards the cylinder
: Take out and examine the
muffler (3), replace if necessary
: Fit the exhaust gasket (1) and
orient it with the tabs (arrows) on
– Remove exhaust gasket the connector of the cylinder
– always use a new exhaust
gasket

34 MS 241 C
6.2 Leak testing
2
Defective oil seals and gaskets or c
cracks in housing are the usual
causes of leaks. Such faults allow
1
supplementary air to enter the

a
engine and upset the fuel-air
mixture. b

2410RA075 TG

2710RA164 TG
This makes adjustment of the
prescribed idle speed difficult, if not
impossible. : Fit the stopper (1) 1122 025 2200 The flange (1) 4224 893 2501 can
and screw it tight be reworked as shown.
Moreover, the transition from idle a = 13 mm
speed to part or full throttle is not b = 39.25 mm
: Screw in spark plug (2) and
smooth. c = 6 mm
tighten it securely
Always start with the vacuum test
and then continue with the pressure – Remove muffler and gasket,
test. b 6.1

The engine can be thoroughly 1

checked for leaks under vacuum
and at gauge pressure using the 2 2
pump 0000 850 1300.
2

2410RA077 TG
6.2.1 Preparations
3 3
– Remove shroud, b 6.4
2410RA076 TG

: Slide sealing plate (1)

0000 855 8106 between cylinder
– Take off the spark plug boot and 1 exhaust port and flange (2)
remove the spark plug
: Position flange (1)
: Tighten screws (3) lightly
– Set the piston to the top 5910 855 4201 on cylinder
dead center (this can be checked exhaust port
through the spark plug hole) The sealing plate must fill the full
width between the screws.
: Screw in screws (2)
– Remove the decompression – do not tighten
– Carefully pull out the carburetor
valve, b 6.9 over the studs and lay it aside
– Do not overextend fuel hose,
b 8.4

MS 241 C 35
 1 4 3 3 2

2410RA078 TG

2310RA080 TG

2410RA081 TG
2 1

: Washer (1) must be fitted : Push the hose (1) of pump : Slide ring (1) to the right
0000 850 1300 onto the – Pressure test
connector (arrow)
: Operate the lever (2) until the
1 : Slide ring (2) to the left pressure gauge (3) indicates a
– Vacuum test pressure of 0.5 bar. If this
pressure remains constant for at
: Operate lever (3) until the least 20 seconds, the engine
pressure gauge (4) indicates a crankcase is airtight
2
2 vacuum of 0.5 bar
– If the pressure drops, the leak
2410RA079 TG

If the vacuum reading remains must be located and the defective

constant, or does not decrease by part replaced
more than 0.3 bar within 20
: Orient flange (1) 1118 850 4200 seconds, it may be assumed that To find the leak, coat the suspect
and push it onto the studs the oil seals are in good condition. area with soapy water and
If the vacuum in the crankcase is pressurize the crankcase. Bubbles
reduced further, the oil seals must will appear if a leak exists.
: Fit flange (1) 1118 850 4200
be replaced, b 6.3.
– After testing, slide the ring on the
: Tightly screw on nuts (2) – After testing, slide the ring on the pump to the left to vent the pump
pump back to the right to vent the – disconnect the hose
pump.
6.2.2 Vacuum test – Remove flange 1118 850 4200
– Continue with pressure test, on intake elbow
Oil seals tend to fail when subjected b 6.2.3
to a vacuum. In other words, the – Refit carburetor, b 8.4
sealing lip lifts away from the
crankshaft during the piston's 6.2.3 Pressure test – Remove flange 5910 855 4201
induction stroke because there is no and sealing plate 0000 855 8106
internal counterpressure.
The same preparatory steps are
required as for the vacuum test, – Refit the muffler, b 6.1
This kind of fault can be detected by
b 6.2.2.
testing with pump 0000 850 1300.
– Press in new stoppers straight
with a blunt tool
– Do not damage stoppers

– Reassemble remaining parts in

reverse order

36 MS 241 C
6.3 Oil seals Installation – Clean the cone of the crankshaft
to ensure it is completely grease-
– Clean the mating surface, b 16 free, b 16
It is not necessary to dismantle the
complete engine if only the oil seals
need to be replaced. – Grease the sealing lips of the – Reassemble remaining parts in
new oil seal, b 16 reverse order
Pull out oil seals using puller
5910 890 4400 and
jaws (profile no. 6) 0000 893 3711. 6.3.2 Clutch side
2
– Remove the clutch, b 4.2
6.3.1 Ignition side

– Remove oil pump, b 12.3

– Remove fan housing, b 9.2 1
– Remove the flywheel, b 7.6

2410RA083 TG
Versions with heating

– Unscrew screws, remove : Fit the installing sleeve (1)

generator and set it aside, 1141 893 4600 1
b 14.7
: Slide the oil seal (2) over the

2410RA085 TG
installing sleeve with the sealing
lip facing the crankcase

– Remove the installing sleeve (1)

: Remove the circlip (1)

1 1
2410RA082 TG

Avoid damage to the crankshaft 2

stub.
2410RA084 TG

– Free the oil seal in its seat by

tapping it with a suitable tube or a
punch. : Orient press sleeve (2)
1143 893 2400 with the
: Position puller (1) 5910 890 4400 collar (arrow) facing the engine

– Clamp the puller arms : Use the press sleeve (2)

1143 893 2400 to install the oil
– Pull out the oil seal seal (1)

The seating face must be flat and

free from burrs.

MS 241 C 37
 : Remove the installing sleeve (1) 6.4 Shroud

1
2
1
2410RA086 TG

2410RA090 TG
2410RA088 TG
Avoid damage to the crankshaft
stub.
: Release quick release
– Free the oil seal in its seat by : Orient press sleeve (1) locks (arrows)
tapping it with a suitable tube or a 1118 893 2401 with the – Using the combination wrench,
punch. collar (arrow) facing the engine turn 1/4 turn counterclockwise

: Position puller (1) 5910 890 4400 : Use the press sleeve (1) : Remove the shroud (1)
1118 893 2401 to install the oil
– Clamp the puller arms seal (2)

– Pull out the oil seal The seating face must be flat and 1
free from burrs.

Installation

– Clean the mating surface, b 16

2410RA091 TG
– Grease the sealing lips of the
new oil seal, b 16
1
: Push out cap (arrow) with drift (1)
2410RA089 TG

: Fit the circlip (1)

1 – Reassemble remaining parts in

reverse order
2410RA087 TG

: Fit the installing sleeve (1)

1141 893 4600

: Slide the oil seal (2) over the

installing sleeve with the sealing
lip facing the crankcase

38 MS 241 C
Installation – Remove the carburetor, b 13.5

– Remove carburetor support,

b 13.8

– Remove air guide shroud, 1

2 b 13.4, versions with manual
fuel pump b 13.4.1, versions

2410RA094 TG
1
with heating b 13.4.2

2410RA092 TG
– Remove the muffler, b 6.1
: Carefully pull off the cylinder (1)
– Remove the decompression
: Push in cap (1) with drift (2) valve, b 6.9
– not for version with ErgoStart
– Reassemble remaining parts in
reverse order – Remove the front handle,
b 10.4
– not for version with heating
6.5 Cylinder 1
– Remove antivibration spring on
front handle, b 10.3.1

2410RA095 TG
Before removing the cylinder,
decide whether or not the – not for version with heating
crankshaft is to be removed.

With cylinder installed : Remove the cylinder gasket (1)

The crankshaft must be prevented
from twisting by blocking the piston
through the spark plug hole in order
to remove the flywheel and clutch.

With cylinder removed

The crankshaft is blocked by
2410RA093 TG

placing the piston on the wooden

assembly block in order to remove
the flywheel and clutch.

2410RA096 TG
– Remove shroud, b 6.4 : Take out the screws (arrows)

– Take off the spark plug boot and

remove the spark plug, b 4 : Examine and clean the mating
surface (arrow), b 16
– Remove fan housing, b 9.2
The mating surface must be in
perfect condition and without any
– Remove short circuit wire,
damage whatsoever. Parts with
b 7.7.2
damaged mating surfaces must be
replaced, b 3.7.
– Remove the control unit, b 7.3

– Remove filter base, b 13.3

MS 241 C 39
 Installation
2 2
2 2
1
1

2410RA097 TG
1

2410RA102 TG
2

2410RA099 TG
: Examine the intake elbow (1), 2 – Coat piston, piston rings and
replace if necessary. Engine inside of cylinder with oil, b 16
operation may be impaired even : Position intake elbow (1)
by the slightest damage, b 3.7 : Fit clamping strap (1)
: Insert and tighten down the 0000 893 2600 around piston
: Remove screws (2) screws (2) and piston rings

: Remove intake elbow (1) – Ensure that piston rings are

correctly positioned, b 6.8

The clamping strap (1) must be

fitted in such a way that the piston
rings do not protrude beyond the
1 piston sides.
2410RA100 TG
2410RA098 TG

: Guide new cylinder gasket (1)

1
over the piston so that the
: Examine and clean the mating tab (arrow) faces the spiked 2
surfaces (arrows), and remove bumper

2410RA103 TG
any gasket residues, b 16

– Clean mating surface on intake

1
elbow, b 16
: Orient cylinder (1) so that the
intake elbow (2) faces the control
The mating surfaces must be in
handle
perfect condition and without any
damage whatsoever. A new cylinder
must be used if the mating surfaces When fitting the cylinder over the
are damaged. piston, ensure that the clamping
2410RA101 TG

strap securely encloses the piston

Always use a new cylinder gasket and that none of the piston rings
after removing the cylinder. protrudes
– danger of breakage.
: Place wooden assembly
block (1) 1108 893 4800
: Slide cylinder over piston; the
between piston and crankcase
clamping strap is removed at the
same time
Avoid damage to the cylinder
gasket.

40 MS 241 C
 6.6 Crankshaft Clutch side half of crankcase

– Drain fuel tank and oil tank, 1

b 1.1
2
– Remove brake band, b 5.2
1

2410RA104 TG
– Remove oil pump, b 12.3

2410RA106 TG
– Remove oil suction hose,
b 12.2
: Remove clamping strap (1) and
wooden assembly block (2)
– Remove brake lever, b 5.3 : Remove the circlip (1)
QuickStop Super, b 5.4
Make certain that the cylinder
gasket is oriented according to the
holes. – Remove the front handle,
b 10.4
Version with heating, b 10.4.1

– Remove the tank housing,

b 13.11.5

– Remove the flywheel, b 7.6

2410RA107 TG
– Version with handle heating
Remove generator, b 14.7
2410RA093 TG

The tools from the assembly tool kit

– Remove the cylinder, b 6.5 5910 007 2205 are used for
removal and installation.
– Push cylinder home as far as – Remove piston, b 6.7
possible : Take out the screws (arrows)
– Remove spiked bumper
: Fit screws (arrows) and secure
cylinder with gasket
Always fit new ball bearings and oil
seals when removing the
: Tighten down the screws through crankshaft, b 6.6.1 and b 6.3.
the holes (arrows) crosswise

– Reassemble remaining parts in

reverse order
2410RA105 TG

1 2

: Remove screws (1) and pull out

chain tensioner (2)

MS 241 C 41
 Ignition side half of crankcase : Align the assembly tool (1) with
the disk (2) 5910 893 2103
against the ignition-side half of
1 the crankcase so that the edge
2 number "24" (arrow) is at the
bottom

2410RA544 TG : Insert three M5 x 72 screws (3)

through the holes marked "24"
1 and screw them as far as

2410RA109 TG
possible into the crankcase half
: Unscrew screw (1), remove
Loctite residue from the threaded
hole if necessary : Remove the gasket (1)

: On versions with quick chain

tensioner, remove side plate (2)
22

24 23

3 22

24

23

22
22
23

2
23

2
24
24

2410RA111 TG
22

24
1
23

22
23
24
2410RA110 TG

1 : Turn the spindle (1)

3 3 counterclockwise until the
crankshaft has been forced out of
2410RA108 TG

the ignition-side half of the

The tools from the assembly tool kit
crankcase
1 5910 007 2201 are used for
removal and installation.
: Unscrew spindle (1) until it no – Use disk 5910 893 2103
longer rests on the crankshaft 1
stub The assembly took kit
5910 007 2201 can be expanded
with the disk 5910 893 2103.
: Push assembly tool (2) from kit
5910 007 2205 onto the
The new assembly tool kit
stud (arrow), twist on and tighten
5910 007 2201 contains all three
the nut
disks.
2410RRA112 TG

: Turn spindle (1) clockwise until : Adjust the spindle (1) of the
the crankshaft stub has been
2
assembly tool
forced out of the ball bearing so that the disk (2) rests against
The crankshaft (1), connecting
the half of the crankcase
rod (2) and the needle bearing
The clutch-side half of the – Left-hand thread
between them make up a complete
crankcase is pulled off in this way
unit and must therefore always be
and the two halves of the crankcase
replaced as a unit.
separated.
– Check the two halves of the
– Replace ball bearings and oil
crankcase and the grooved ball
seals, b 6.6.1 and b 6.3
bearing, replace if necessary,
b 6.6.1

– Before installation, clean the

crankshaft, b 16

42 MS 241 C
Installation
2
Ignition side half of crankcase

Avoid damage to the crankshaft

stub.
1
Examine and clean the mating

5902RA135 TG

2410RA114 TG
surfaces of the ignition-side half of
the crankcase (including the
cylinder sealing surface) – the
1
sealing face must not display any
signs of damage, b 16. If the inner race cannot be heated, : Fit the screw sleeve (2) over the
the crankshaft can be drawn into the thread of the conical crankshaft
crankcase with the assembly tool stub (1) and screw it on
5910 007 2201.
– Use disk 5910 893 2103.

: Screw the threaded sleeve (1)

5910 893 2420 onto the
completely screwed in spindle as
2
22

far as it will go 24 23

22

24
2410RA113 TG

– Coat the tapered crankshaft stub 23

with oil. 23
24
22

2410RA115 TG
1
: Orient the crankshaft with the 2
.
conical crankshaft stub (arrow)
facing the ignition-side ball : By turning the spindle screw (1),
bearing position disk 5910 893 2103
against the ignition-side half of
– Wear protective gloves the crankcase and orient it so that
– risk of burns the edge number "24" is at the
bottom
2410RA113 TG

– Heat only the inner race of the

ball bearing to approx. 150 °C : Insert M5x72 screws (2) through
(300 °F) the holes marked "24"
– anti-twist device
: Align the crankshaft with the
: Press crankshaft stub fully home
conical crankshaft stub (arrow) : Turn the spindle screw (1)
facing the ignition-side ball clockwise
The crankshaft must be fitted bearing and push it home
rapidly, as the heat is transmitted to
the crankshaft stub and the inner – Draw the ignition-side half of the
bearing race contracts. crankcase in as far as possible

MS 241 C 43
 1 1

22

24 23

22

24

23

2410RA116 TG

2410RA118 TG

2410RA120 TG
22
23
24

The crankshaft also turns when it is : Fit a new gasket (1) and secure it – Wear protective gloves
drawn in with the installing tool. For at the guide sleeves (arrows) – risk of burns
this reason, ensure that the rod
eye (1) always faces upwards – Coat the cylindrical crankshaft – Heat only the inner race of the
towards the cylinder. stub with oil ball bearing to approx. 150 °C
(300 °F)
– Remove the installing tool
Clutch side half of crankcase – Align the crankcase half with the
cylindrical crankshaft stub and
Avoid damage to the crankshaft the two screws and position it
stub.
: Push the crankcase home until it
Examine and clean the mating makes contact
surfaces of the clutch-side half of
the crankcase (including the
The crankcase must be fitted
cylinder sealing surface) – the
rapidly, as the heat is transmitted to
sealing face must not display any
2410RA117 TG

the crankshaft stub and the inner

signs of damage, b 16.
bearing race contracts

If it is not possible to heat the inner

: Screw two screws (arrows) race, the crankcase half is drawn in
M5x72 into the holes on the with the assembly tool from kit
ignition side 5910 007 2205.
– for guidance and to prevent
twisting – Coat the cylindrical crankshaft
stub with oil
2410RA119 TG

– Align the crankcase half with the

cylindrical crankshaft stub and
the two screws and position it

Ensure that the guide

sleeves (arrows) line up with the
holes and that the housing gasket is
not jammed or buckled.

44 MS 241 C
 2410RA121 TG

2410RA119 TG
165RA133 TG
1

– By turning it, screw the spindle : Hold crankshaft steady and Ensure that the guide
completely into the assembly tool screw threaded sleeve onto sleeves (arrows) line up with the
thread of crankshaft stub by holes and that the housing gasket is
: Screw the threaded sleeve (1) turning the spindle not jammed or buckled.
5910 893 2409 onto the spindle counterclockwise
as far as it will go – Continue turning the spindle of
– Left-hand thread – Release crankshaft and hold the assembly tool until the gap
assembly tool steady and between the halves of the
continue turning the spindle until crankcase is closed
the assembly tool rests against
the crankcase half. – Unscrew nuts

– Screw nut onto the stud and – Turn the spindle clockwise to
tighten it by hand remove the assembly tool

– Remove the two M5x72 screws

which were fitted to prevent
0001RA494 TG

twisting

: Fit threaded sleeve on crankshaft

stub (arrow) and push assembly
tool over the studs
2410RA122 TG

: Turn spindle (1)

counterclockwise until the 2410RA107 TG

crankcase half rests against the

guide sleeves
: Insert the screws (arrows) and
tighten them down crosswise

MS 241 C 45
 6.6.1 Ball bearing / crankcase Ignition-side half of the
crankcase
The two halves of the crankcase
can be replaced individually if they
are defective.

New crankcases are delivered with

2410RA545 TG the relevant components pre-
assembled
1 – see spare parts list

2410RA124 TG
– For versions with quick chain Those parts which are not supplied
tensioner, fit side plate with the new crankcase must be
removed from the old crankcase,
examined and replaced if : Carefully drive the oil seal out
: Coat screw (1) with Loctite, necessary.
screw in and tighten, b 16 with a punch
When fitting a new crankcase, the
: Examine and clean the
machine's serial number must be
crankcase, replace if necessary.
stamped on the crankcase with
1 2.5 mm figure stamps.
– Replace ball bearings if the
If the original crankcase is reused, crankcase is in good condition
the oil seals and grooved ball
bearings must be replaced, all
gasket residues removed and the
mating surfaces cleaned
2410RA123 TG

thoroughly. The mating surfaces

must be absolutely flawless and
clean to guarantee a perfect seal,
b 16.
: Fit the circlip (1)
1
Examine both halves of the

2410RA125 TG
– Examine and install the piston, crankcase for cracks and check all
b 6.7 mating surfaces for signs of
damage.
– Examine and install the cylinder,
b 6.5 – Refer also to troubleshooting, – Heat the bearing seat of the ball
b 3.7 bearing to approx. 150 °C
(300 °F)
– Install chain tensioner, b 5.7
– Remove crankshaft, b 6.6
The bearing (1) drops out of its own
– Reassemble remaining parts in
accord when this temperature is
reverse order – Wear protective gloves
reached.
– risk of burns

46 MS 241 C
Installation – Replace ball bearings if the The ball bearing must be fitted
crankcase is in good condition rapidly, as it absorbs heat and
expands.

– Check seat of ball bearing, if

necessary, use press arbor
1118 893 7200 to carefully press
the ball bearing fully home until it
rests against the oil pump

2410RA126 TG
– Remove oil pump, b 12.3
1

2410RA128 TG
– Install crankshaft, b 6.6
– Heat the bearing seat of the ball
bearing to approx. 150 °C – Install the oil seals, b 6.3
(300 °F) – Heat the bearing seat of the ball
bearing to approx. 150 °C – Reassemble remaining parts in
– Position ball bearing so that the (300 °F) reverse order
open side (balls visible) faces the
inside of the crankcase The bearing (1) drops out of its own
accord when this temperature is 6.7 Piston
: Press the grooved ball bearing reached.
home as far as possible
Before removing the cylinder,
decide whether the crankshaft is to
The ball bearing must be fitted Installation
be removed, b 6.6
rapidly, as it absorbs heat and
expands. Because the clutch side half of the
– Remove the cylinder, b 6.5
crankcase does not have a fixed
– Check seat of ball bearing, if bearing seat, the oil pump must be
removed beforehand The clutch side snap ring is not
necessary, use press arbor
– The oil pump serves as a removed.
1118 893 7200 to press the ball
bearing fully home in the ball reference
bearing seat
– Install oil pump, b 12.3

Clutch-side half of the crankcase

2410RA130 TG
2410RA129 TG

: Pry the hookless snap ring out of

2410RA127 TG

the recess (arrow) on the ignition

side with a suitable tool
– Heat the bearing seat of the ball
: Carefully drive the oil seal out bearing to approx. 150 °C
with a punch (300 °F)

– Examine and clean the – Position ball bearing so that the

crankcase, replace if necessary. centering ring (arrow) points
towards the oil pump

: Press ball bearing fully home (oil

pump)

MS 241 C 47
 Installation
1
1

2410RA131 TG

5904RA089 TG
2 2 1

2410RA133 TG
: Push assembly drift (1) : Remove the sleeve (1)
1110 893 4700 through the 5910 893 1707 from the installing
installed snap ring – Coat needle bearing with oil and tool (2) 5910 890 2210
slide it into the rod eye
: Push the piston pin (2) out of the
piston with the assembly drift (1) Line up the piston so that the
1110 893 4700 arrow (arrow) in the piston base
points towards the spiked
If the piston pin is stuck, tap the end bumper (exhaust port)
of the drift gently with a hammer to
loosen it. The assembly drift can be inserted
The piston must be held steady through the fitted snap ring.
during this process to ensure that

165RA153 TG
jolts are not transmitted to the – Position the piston on the rod eye
connecting rod. 2 1
: Push assembly drift (1)
– Remove the piston 1110 893 4700 with the stub end
: Attach the snap ring (1) to the
first through piston hole and rod
magnet (2) and align it so that the
– Examine the piston rings and eye (needle cage) and secure
snap ring gap is on the flat
replace if necessary, b 6.8 the piston
side (arrow)

1 1 2 2 1
2410RA134 TG
2410RA132 TG

5904RA090 TG

: Take out the needle bearing (1), – Coat the piston pin (1) with oil
: Push the slotted opening of the
examine and clean it, replace if sleeve over the magnet and snap
necessary : Fit the piston pin (1) on the stub ring
of the assembly drift (2) and slide
it into the piston
The inner pin (1) must point towards
the flat face of the tool's shank (2).

48 MS 241 C
 6.8 Piston rings

– Remove piston, b 6.7

– Remove piston rings from piston

5904RA091 TG

2410RA136 TG
Press the assembly tool down in the : Position the installing tool
sleeve until the magnet is at the end 5910 890 2210 with the taper
of the guide slits. sleeve on the piston boss, hold
the piston steady and press the

2410RA138 TG
tool shank home until the snap
ring slips into the groove

The tool must be precisely aligned

in axial direction of the piston pin. : Use a piece of old piston ring to
scrape the grooves (arrows)
clean
216RA178 TG

: Remove sleeve and fit it over the

opposite shaft end of the
assembly tool, with the internal
2410RA137 TG

pin pointing towards the flat

surface.

2410RA139 TG
– Examine the piston rings and
replace if necessary, b 6.8
: Align the new piston rings so that
– Install the cylinder, b 6.5 the radiuses at the ends of the
ring (arrows) face upwards

1 – Reassemble remaining parts in

reverse order
2410RA135 TG

The snap ring (1) must be fitted so

that the gap in the ring (arrow)
points upwards in axial direction of
the piston.

MS 241 C 49
 6.9 Decompression valve

– Remove shroud, b 6.4

1
2410RA140 TG

– Carefully slide the piston rings

over the piston

2410RA141 TG
– danger of breakage

: Position the piston rings so that

the radiuses at the ring gaps
: Unscrew decompression
encircle the fixing pins in the
valve (1)
piston grooves (arrows)

: Check the correct installed

position of the piston rings
again (arrows)

– Install the piston, b 6.7

– Reassemble remaining parts in

reverse order
5902RA164 TG

: Examine the sealing

cone (arrow) on the
decompression valve for signs of
damage

– Use a new decompression valve

if the sealing cone on the
decompression valve does not
seal tightly or is damaged

– Fit the decompression valve by

hand and screw it in

– Screw the decompression valve

tight

– Reassemble remaining parts in

reverse order

50 MS 241 C
7. Ignition system

Exercise extreme caution while Testing of the ignition module is not 7.3 Control unit
carrying out maintenance and repair limited to only a spark test. If no
work on the ignition system. The ignition spark is obtained or other
– Remove fan housing, b 9.2
high voltages which occur can functions do not work, a diagnosis
cause serious or fatal accidents. must be carried out according to the
troubleshooting chart; replace – Unplug the spark plug boot
Troubleshooting on the ignition control unit or M-Tronic wiring
system should always start with the harness if necessary.
spark plug, b 3.5
3 1
– Remove fan housing, b 9.2 7.1 Ignition timing

Ignition timing is fixed and cannot

be adjusted during repair work.
4
Since there is no mechanical wear

2410RA144 TG
1 in these systems, ignition timing
cannot get out of adjustment during 2
operation.
: Remove holders (1) and (2)
carefully from the slits (arrows)
2410RA142 TG

7.2 Pre-separator and open

2 3
– Remove fan housing, b 9.2 : Pull the ignition lead (3) out of the
The contactless electronic ignition guide
system basically consists of a
control unit (1), flywheel (2),
switchgear (3) and solenoid
valve (4).
2
The ignition module accommodates
all the components required to
control the ignition timing and fuel
1 1
flow. There are only three electrical
2410RA143 TG

connections leaving the control unit:

2410RA145 TG
1. High voltage output for the
ignition lead.
: Remove screw (1)
2. Connector tab for black : Lift retaining tab (arrow) and
lead – short circuit wire. : Remove pre-separator (2), check remove angled plug (1)
and replace if necessary
3. Connector tab for red lead – Examine insulating sleeve of the
– M-Tronic. – Reassemble parts in reverse angled plug, clean or replace if
order necessary, b 7.7.2

MS 241 C 51
 Installation
1 1

1
2
2410RA146 TG

2410RA150 TG
1

2410RA148 TG
: Remove screws (1) with washers : Position ground wire (1) so that
the cable lug is pressed fully
– Remove control unit : Position cable holder (1) on the home (arrow) and the crimped
cylinder and secure it with the side faces the screw head
pins on the cylindrical raised
parts : Insert screw (2) with washer – do
not tighten
3
1

1
3
2410RA147 TG

2 2
2410RA149 TG

2410RA151 TG
: Remove wiring harness (1) and
ground wire (2) from the
guides (arrows) and remove 1
cable holder (3) : Hold cable holder (1) against
cylinder and position control : Push back ignition module and
unit (2) slide setting gauge (1)
– Check ignition lead, replace if
necessary 1111 890 6400 between the legs
: Insert screw (3) with washer – do of the ignition module and the
not tighten magnetic poles of the flywheel
– Examine the spark plug boot,
replace if necessary, b 7.5
On the cable lug of the ground wire,
the crimped side must face the
– Troubleshooting, b 3.5
screw head.

52 MS 241 C
 1 1

2
1 2
2
N
2
S

2410RA152 TG

2410RA154 TG

2410RA156 TG
Shown without setting gauge for a : Orient angled plug (1) so that the : Orient wiring harness (1) so that
better view. retaining tab (2) faces the muffler the protective tube (2) lines up
with the leading edge (arrow) and
– Flywheel must turn freely : Press the angled plug (1) straight the red M-Tronic lead is
onto the connector tags until the underneath the short-circuit
: Turn the flywheel until the retaining tab (2) snaps into place wire (black)
magnet poles "N/S" (arrows) are – Do not insert the angled plug on
at the control unit (1) a slant or tilt it

: Press control unit (1) against the 1

setting gauge and tighten
screws (2) – the cable lug of the a
ground wire must be fully seated
1
– Remove the setting gauge
4

2410RA157 TG
– Checking correct functioning
– Turn the flywheel: it must not
2410RA155 TG

touch the control unit

3 2 : Press wiring harness (1)
completely into the
Protective tube (2) must be guides (arrows)
positioned snug against the
grommet in the air guide shroud.

: Press the wiring harness (1) into

1 the guide so that the protective
tube (2) a = ca. 8 mm is seated in
1
the guide (arrow)
2410RA153 TG

– Ground wire is routed 2

underneath the wiring harness
2410RA158 TG

: Press ground wire (1) completely : Push the holder (3) into the slit of
into the guide (arrow) the cable holder (4) until it clicks
– Ground wire is routed into place
underneath the wiring harness : Plug the spark plug boot (1) onto
the spark plug so that it runs
parallel to the air guide shroud
underneath the tab (2)

MS 241 C 53
 7.4 Spark test check control The engine may start and
unit accelerate during the test.

If a spark is visible, the ignition

The ignition test refers only to a
system is in order.
spark test, not the general functions
of the control unit; these are
described in the M-Tronic chapter, – If no spark is visible in the
window (2), check the ignition
2410RA159 TG b 8.2, b 8.5.
system with the aid of the
troubleshooting chart, b 7.8,
1 To spark test the control unit, use
b 8.5
either the ZAT 4 ignition system
: Press ignition lead (1) completely tester 5910 850 4503 or the
into the guide (arrow) ZAT 3 ignition system tester
5910 850 4520. Using the ZAT 3 ignition system
– Note routing of the ignition lead,
tester 5910 850 4520
see illustration
Using the ZAT 4 ignition system
Ignition lead and spark plug boot tester 5910 850 4503
must not touch the air guide shroud.

1
1

165RA184 TG
2 3 4
165RA183 TG

– Before starting the test, install a

2410RA160 TG

1 2 3 new spark plug and tighten it

down firmly
– Before starting the test, install a
new spark plug in the cylinder : Connect the spark plug boot to
: Press the holder (1) into the and tighten it down firmly. the terminal (2)
slit (arrow) until it clicks into place
: Connect the spark plug boot to : Attach ground terminal (1) to the
– Reassemble remaining parts in
the input terminal (1). Push the spark plug
reverse order
tester's output terminal (3) onto
the spark plug : Use adjusting knob (4) to set
spark gap to approx. 2 mm,
Danger! High voltage – risk of see window (3)
electrocution.

– Crank the engine quickly with the

rewind starter and check
sparkover in the window (2) of
the ignition system tester

54 MS 241 C
 5

2310RA127 TG

2310RA128 TG
165RA185 TG
2 3 4

While using the ZAT 3, hold it only : Use suitable pliers to pull the – Apply STIHL press fluid to the
by the handle (4) or position it in a torsion spring out of the spark inside of the spark plug boot,
safe place. Keep fingers or other plug boot b 16
parts of your body at least 1 cm
away from the spark window (3), – Unhook the torsion spring from : Push the ignition lead and torsion
high-voltage connection (2), ground the ignition lead spring into the spark plug boot
connection (5) and the ground
terminal (1).
– Pull the boot off the ignition lead
Danger! High voltage – risk of
electrocution. – Check ignition lead, replace if
necessary, b 7.5.1
– Crank the engine quickly with the
rewind starter and check
sparkover in the window (3) of Installation
the ignition system tester

2310RA129 TG
The engine may start and
accelerate during the test.

If a spark is visible in the : Ensure that the torsion

window (3), the ignition system is in spring (arrow) is located in the
order. recess
165RA188 TG

– If no spark is visible in the – Plug spark plug boot onto spark

window (3), check the ignition plug and press ignition lead
system with the aid of the completely into the guide, b 7.3
troubleshooting chart, b 7.8
– With a new ignition module, use a
pointed tool to pierce the center Ignition lead and spark plug boot
of the new lead's insulation must not touch the air guide shroud.
7.5 Spark plug boot approx. 13 mm from the end of
the ignition lead – Reassemble remaining parts in
– Remove shroud, b 6.4 reverse order
: Pinch the hook of the torsion
– Unplug spark plug boot and pull spring into the center of the
ignition lead out of the guides, ignition lead (arrow) where it has
b 7.3 been pierced

MS 241 C 55
7.5.1 Ignition lead – Before twisting in the ignition – Block the piston with the locking
lead, fill the coil tower with STIHL strip, b 4
multi-purpose grease, b 16
The ignition lead is built into the high
voltage output of the control unit. If
the ignition lead is damaged, the Do not use either graphite grease or
control unit must be replaced. silicone insulating paste.

– Remove spark plug boot, b 7.5

1
– Remove the control unit, b 7.3 2

2410RA164 TG
1
2

2410RA162 TG
: Unscrew the flywheel nut (1)
1

– Push grommet onto ignition lead 3

2410RA161 TG

: Twist ignition lead (2) into control

unit
: Pull grommet (1) off of high-
1
voltage output (arrow) : Push on the grommet (1)

2410RA163 TG
: Twist ignition lead (2) out of – Install control unit and adjust air
control unit gap control unit/ flywheel, b 7.3 2 1

– Pull the grommet off the ignition – Reassemble remaining parts in : Screw the screws (1) of the
lead reverse order puller (3) 5910 890 4504 into the
flywheel as far as they will go
– Ensure that the screws are
7.6 Flywheel screwed in uniformly

– For versions with heating, only M

For versions with ErgoStart, the new
5 x 25 screws can be used to
puller 5910 890 4504 with extended
fasten the puller
clamping bridge must be used. The
– Generator can be damaged
previous puller 1135 890 4500 is
being replaced by the new puller,
but can still be used for the standard – For versions with ErgoStart, do
165RA191 TG

versions. not damage the pawls

: Turn screw (2) clockwise until the

– Remove shroud, b 6.4 flywheel comes off the crankshaft
: Use a pointed tool to pierce the
stub
center of the end of the new
ignition lead, which is to be – Remove fan housing, b 9.2
twisted into the control unit. : Unscrew puller (3)
5910 890 4504 from flywheel

56 MS 241 C
 – Reassemble remaining parts in 7.7.2 Removal and installation
reverse order
– Remove shroud, b 6.4

7.7 Short circuit wire

– Unplug the spark plug boot

Ground wire, short-circuit wire and – Remove fan housing, b 9.2

0001RA167 TG
M-Tronic lead are all combined into
one wiring harness.
– Remove choke rod, b 11.4
Make a contact test of the short
The flywheel and magnet circuit wire if the spark plug and
poles (arrows) must not display any ignition lead with spark plug boot
signs of damage or blue are in order.
1
discoloration; replace flywheel if
necessary.
7.7.1 Contact test
– The magnet ring must also be
examined for signs of damage in – Remove fan housing, b 9.2
versions with handle heating,

2410RA165 TG
b 7.6
– Move the Master Control lever to
"0" 2
– With versions with ErgoStart
pawls, check for damage and : Remove holders (1) and (2)
smoothness of motion, b 9.4. carefully from the slits (arrows)
and open

Installation

Flywheel and crankshaft stub must

be free from grease for installation.
2310RA155 TG

2410RA166 TG
– Blade receptacle of the short-
circuit wire must touch the
contact spring (arrow) in position
"0"
: Lift retaining tab (arrow) and
2310RA110 TG

remove angled plug (1)

Also carry out a contact and
continuity test of the ground wire
between cable lug and contact
Ensure that the machined key spring, replace wiring harness if
(arrow) engages the slot in the necessary.
crankshaft.
– If no fault can be found, test the
– Set the air gap between control M-Tronic in accordance with flow
unit and flywheel, b 7.3 chart, b 7.8

– Reassemble parts in reverse

order

MS 241 C 57
 1

1
1
2410RA167 TG

2410RA170 TG

2410RA171 TG
2

: Remove screw (1) with washer : Remove blade receptacle (1) of : Pull plug connector (1) out of the
and remove ground wire cable the carburetor heating lead carburetor support mount (arrow)
lug (2)

Versions with manual fuel pump

2 1

1 2

2410RA172 TG
2
2410RA168 TG

2410RA220 TG

3 : Hold the jack (1), press the

: Remove wiring harness (1) and tab (arrow) and pull out the
ground wire (2) from the : Push out the holder (1) with the plug (2) – do not tug on the leads
guides (arrows) fuel pump at the air guide
shroud (2), remove fuel hose (3) – Turn the carburetor a little in the
at the carburetor (arrow) and lay direction of the control handle
Versions with heating it on top of the air guide shroud – Do not overextend fuel hose

All versions

– Remove filter base, b 13.3

1 – Remove contact spring, b 7.7.4

– Remove switch shaft on filter 1

2410RA169 TG

base, b 11.1
2410RA173 TG

: Pull out carburetor heating

lead (1) at the guide (arrow) : Remove the plug (1)

58 MS 241 C
 1 2
2

2410RA174 TG

2410RA177 TG

2410RA180 TG
1

: Remove diagnostic jack (1) with : Pull out grommet (1) with wiring : Pull the retaining tab (1) in the
connector housing (2) from the harness direction of the leads and open
guides (arrows) the cover (2)

1
1 1 1

2410RA178 TG
2410RA175 TG

2410RA181 TG
: Remove ground wire (1) from the
: Pry out and remove the cable guides (arrows) : Pull blade receptacles (1) out of
holder (1) at the pin (arrow) the insulating sleeve (2)

– Check blade receptacles and

insulating sleeves, clean or
1 replace insulating sleeves if
necessary
2
With a new wiring harness, the
grommets and the plugs as well as
the insulating sleeve are pre-
2410RA179 TG

assembled.
2410RA176 TG

: Remove ground wire (1) from the

: Remove wiring harness (1) from guide (arrow)
the guides (arrows) of the air
guide shroud : Remove the switch shaft (2)

MS 241 C 59
Installation

The ground wire (4) must be routed

1 1 behind the protective tube (2)
– facing the cylinder.

2
1
2 2410RA182 TG

2410RA184 TG
3

: Push the blade receptacle (1) of : Close and lock the cover (1) so
2

2410RA187 TG
the red lead (M-Tronic) into the that the tab (2) engages the
rear receptacle (arrow) of the slit (arrow) of the retaining tab (3)
insulating sleeve (2) – the retaining tab must fit snugly
– Crimped side faces forward against the insulating sleeve
: Push the grommet (1) into the
The leads must not be reversed. opening (arrow) in the air guide
shroud (2) until it is flush with the
1 2 edge of the air guide shroud

1
3 1

2
2410RA185 TG
2410RA183 TG

2410RA189 TG
The protective tube (1) must rest
against the grommet (2).
: Push the blade receptacle (1) of 2 4
the black lead (short-circuit wire) : If necessary, push the wiring
into the front receptacle (arrow) harness towards the grommet (2) : Orient wiring harness so that the
of the insulating sleeve (2) until the protective tube (1) rests red lead (1) is above and the
– Crimped side faces forward against the grommet (2) black lead (2) is underneath the
ground wire (3)
The leads must not be reversed.
Starting at the protective tube (4),
4 the ground wire branches out into a
1 thin black lead (M-Tronic) and a
thick blue lead (short-circuit wire).

3 When inserting the ground wire, the

small guide rib (arrow) must be
between these two leads
2410RA186 TG

: Orient the wiring harness (1) so

that the protective tube (2) and
angled plug (3) face the control
unit

60 MS 241 C
 1 4

2
2
1
1

2410RA190 TG

2410RA192 TG

2410RA194 TG
3 5 2

: Press the red M-Tronic lead (1), : Check that the leads are properly : Press the diagnostic jack (1) into
ground wire (2) and black seated in the guides and press the mount so that it is seated
lead (3) of the short-circuit wire the cable holder (1) with the completely in the recess (arrows)
all the way into the pin (arrow) into the mount until it and the tabs (2) snap into place
guides (arrows) snaps into place

The protective tube (4) must start at

the beginning of the rib and
protective tube (5) must rest against 3
the beginning of the rib.
2
1

2410RA195 TG
1
2410RA193 TG

: Press plug (1) into the mount as

: Orient diagnostic jack (1) so that far as it will go
2410RA191 TG

the black leads (2) face the

control handle
1
: Press diagnostic jack (1) and 1
: Slide cable holder (1) with the connector housing (3) into the
hinge into the slot (arrow) of the guides (arrows)
air guide shroud

: Turn the cable holder (1) towards

the cylinder and position it 2410RA196 TG

: Using wiring tool 5910 890 4000,

press the blue ground wire (1)
and black short-circuit wire (2)
into the guide (arrow) so that the
wires are snug against the air
guide shroud

MS 241 C 61
 1 3 2 1

2
1

2410RA188 TG

2410RA199 TG

2410RA201 TG
2

: Orient plug (1) and jack (2) that : Slide the blade receptacle (1) of : Check the routing of the blue
the tab (3) lines up with the the blue ground wire, with the ground wire (1) and black short-
mount (arrow) – do not twist the crimped side facing the cam (2), circuit wire (2), if necessary,
leads into the guide (arrow) as far as it press them completely into the
will go guide (arrow) using wiring tool
: Plug connector (1) into jack (2) 5910 890 4000 – wires must rest
until the tab (3) clicks into place in snug against the air guide shroud
the mount (arrow)

1
2
2 1
2410RA200 TG

2410RA202 TG
2410RA197 TG

: Hook ground wire (1) into the

guides (arrows)
: Using wiring tool 5910 890 4000,
: Press the plug connection (1) – Push switch shaft onto filter base, press the blue ground wire (1)
into the mount (2) of the b 11.1 and black short-circuit wire (2)
carburetor support so that the into the guides so that the
tab (arrow) engages in the recess markings (arrows) are located at
– Install contact spring, b 7.7.4
of the plug connection the guide ribs

– Install filter base, b 13.3

– Push on the carburetor and – Conduct a function test of the
observe cable routing as well as switch shaft, b 11.1
installation position of the
M-Tronic and, if present, the
heating system, b 8.4

62 MS 241 C
Versions with heating : Press fuel return line (3)
completely into the guide (arrow)
1

2410RA204 TG
2410RA198 TG
: Press ground wire (1) completely

2410RA227 TG
into the guide (arrow)
: Orient blade receptacle (1) so 1 – Ground wire is routed
that the crimped side faces the underneath the wiring harness
carburetor Push the new fuel suction hose (1)
completely onto the
: Press blade receptacle (1) onto connectors (arrows)
the connector tab (arrow) of the 1
heating switch as far as it will go
All versions

2
1

2410RA205 TG
1
: Orient angled plug (1) so that the
2410RA203 TG

retaining tab (2) faces the muffler

2410RA169 TG

2 4 3 : Press the angled plug (1) straight

onto the connector tags until the
: Press carburetor heating lead (1) Ground wire: Crimped side of the retaining tab (2) snaps into place
completely into the guide (arrow) cable lug (1) must be visible. – Do not insert the angled plug on
a slant or tilt it
: Position cable lug (1) between
control unit (2) and stop (3)
Versions with manual fuel pump

: Insert screw (4) with washer and

tighten
2

1
2410RA226 TG

: Push the holder (1) with the fuel

pump into the recess in the air
guide shroud (2) as far as it will
go

MS 241 C 63
 7.7.4 Contact spring
a 1
The short-circuit wire must be
1 seated firmly in the eye of the
contact spring, if necessary, carry
4 out a contact and continuity test,
b 7.7.1.
2410RA155 TG

2410RA207 TG
– Remove the filter base from the
3 2 studs, b 13.3

Protective tube (2) must be : Press wiring harness (1)

positioned snug against the completely into the
grommet in the air guide shroud. guides (arrows)

: Press the wiring harness (1) into – Check the air gap between
the guide so that the protective 1
control unit and flywheel, adjust if
tube (2) a = approx. 8 mm is necessary, b 7.3
seated in the guide (arrow)
– Ground wire is routed

2410RA209 TG
underneath the wiring harness
2 1
: Push the holder (3) into the slit of
the cable holder (4) until it clicks
: Turn filter base (1) to the side
into place

1
1
2410RA208 TG

2 Ignition lead (1) must be seated 2

completely in the guide.

2310RA151 TG
2410RA206 TG

: Press the holder (2) carefully into

the slit (arrow) until it clicks into
place
: Lift contact spring (1) slightly and
: Orient wiring harness (1) so that – Conduct a function test of the guide it over the tab (arrow)
the protective tube (2) lines up switch shaft, b 11.1
with the leading edge (arrow) and
the red M-Tronic lead is : Press contact spring (1) out of
– Reassemble remaining parts in the guides in the filter base (2)
underneath the short-circuit
reverse order
wire (black)

7.7.3 Ground wire

Testing and installation of ground

wire is the same as for the short-
circuit wire

– Check contacts and operation,

b 7.7

64 MS 241 C
 2

1
1
2 1

2410RA210 TG

2410RA212 TG

2310RA154 TG
: Press contact sleeve (1) of the : Position contact spring (1) : Push the contact spring (1) into
short-circuit wire out of the against the guide (arrows) the guide (arrows) as far it will go,
contact spring (2) until the tab surrounds the
: Lift contact spring (1) slightly at contact spring
– Examine contact spring, replace the connection of the short-circuit
if necessary wire and guide it over the tab (2) – Install filter base, b 13.3
– do not overextend the contact
spring
Installation

2310RA155 TG
1
2410RA211 TG

2310RA153 TG

: Checking correct functioning

– Blade receptacle of the short-
: Push the contact sleeve (1) of the Before pushing the contact circuit wire must touch the
short-circuit wire into the spring (1) all the way in, lift it slightly contact spring (arrow) in position
eye (arrow) of the contact and guide it over the switch shaft – "0"
spring (2) as far as it will go 2 mm maximum.
– Reassemble remaining parts in
reverse order

MS 241 C 65
7.8 Troubleshooting, ignition system

Engine does not run

Stop switch:
– in position "F"?

Check spark plug:

– Smeared with oil, black?
– Sooted?
– Electrode gap correct?
– Contacts shorted (threads)?
– Clean, adjust or replace spark plug,
b 7.5

Check spark plug boot:

– Firmly seated on spark plug (torsion
spring)?
– Torsion spring hook in center of ignition
lead?
– Spark plug boot damaged?
– Replace spark plug boot and/or torsion
spring if necessary,
b 7.5

Check ignition:
with ZAT 3 or ZAT 4
(use ZAT 3 as main spark gap
see TI 32.94),
b 7.4

66 MS 241 C
 1

Spark yes
present?

no

Air gap:
– Check control unit/ flywheel,
– adjust if necessary, b 7.3

Check flywheel:
– Have pole shoes turned blue?
– Replace flywheel if necessary,
b 7.6

Check short circuit wire:

– Wire damaged?
– Plug connections firmly seated?
– Check continuity, replace wiring harness if
necessary, b 7.7.1

Check ignition lead:

– Severe chafing?
– Spark plug boot: Holes / cracks?
– Resistance of spark plug boot to ground:
Required 1.5...12 kΩ
– Check resistance of spark plug lead to
ground, (spark plug boot and control unit have
been removed)
Value: Required < 10 Ω,
replace spark plug boot and/or ignition module
if necessary,
b 7.5.1

2 3

MS 241 C 67
 2 3

Switch shaft
Check correct operation:
– Short circuit wire chafed?
– Function between contact spring and
contact of the switch shaft:
– Position "F" = no connection
– Position "0" = connection
– Replace wiring harness if necessary,
b 11.1

Spark yes
present?

no

Control unit
needs to be replaced,
b 7.3

yes Machine no
runs?

Engine runs smoothly, – Look for fault in fuel or carburetor

troubleshooting procedure system
completed – Check engine for leaks
– Check position of flywheel on
crankshaft,
b 3.6, b 6.2

68 MS 241 C
8. M-Tronic

8.1 Calibrating the control If the control unit or carburetor is

unit replaced during servicing...

– Remove the saw chain and guide

If the outstanding running behavior
bar
and usual performance or maximum
speed of the engine can no longer
be attained, the usual engine – Reinstall the chain sprocket
performance can be attained again cover

2410RA546 TG
by calibrating the control unit.
– Set Master Control lever to
A regulating cycle only starts if the Start }
The fully electronic M-Tronic engine machine is operated for
management system controls the approximately 2 seconds under – Start machine – do not blip the
ignition timing and fuel flow, taking constant conditions. throttle trigger
all external conditions into account.
If the maximum speed is not After completion of the following
A basic or standard setting of the procedure, the Master Control lever
carburetor is no longer required. reached...
must be moved from Start } to
The M-Tronic electronically adjusts STOP 0 without pressing the throttle
the fuel-air mixture in the carburetor. – Examine air filter, clean or
replace if necessary, b 13.1 trigger.
The M-Tronic controls all operating – Let the machine warm up for at
states such as start, idle, part – Examine the spark arresting least 60 seconds in the Start }
throttle and full throttle while screen (if installed); clean or position and then move the
accounting for the external replace it if necessary, b 6.1 Master Control lever to STOP 0
conditions, e.g., use at varying – Calibration is completed
attitudes, as well as changing – Check chain tension, adjust if
temperatures or fuel quality – the necessary
carburetor does not have any The control unit is adjusted to the
adjusting screws. carburetor while the engine runs in
– Check chain lubrication the position Start }.
Troubleshooting and test
procedures are described in the – Set Master Control lever to The machine must be switched off
Start } immediately for the information to
following chapters, Testing, b 8.2,
Troubleshooting, b 8.5. be stored in the control unit.
– Start engine and let it warm up

– Carry out five uniform cuts to

length
– speed between 8000 rpm and
11200 rpm, log diameter
approx. 30 cm

– If the outstanding running

behavior and the usual
performance are not attained,
continue troubleshooting and test
procedures as described under
Testing, b 8.2,
Troubleshooting, b 8.5

MS 241 C 69
8.2 Testing
8.2.1 Test preparations

The following steps must be carried

out before testing. 1
1
– Carry out troubleshooting

2410RA213 TG

2410RA216 TG
according to troubleshooting
chart, b 8.5

– Remove shroud, b 6.4

: Remove diagnostic jack (1) from : Press the diagnostic jack (1) into
the guide (arrow) the mount (arrow) until it is fully
– Remove the air filter, b 13.1 home

– Remove coarse dirt from around – Reassemble remaining parts in

the screwed connections, control reverse order
unit, switchgear, solenoid valve
and diagnostic jack
8.2.3 Check screwed and plug
connections as well as
8.2.2 Connect the test lead 2410RA214 TG switch

– Remove shroud, b 6.4 – Carry out test preparations,

1 2 b 8.2.1
– Remove the air filter, b 13.1
: Orient the plug (1) of the There must be a reliable connection
M-Tronic test lead for communication between control
5910 840 0903 so that the unit, switching device and solenoid
angled shapes (arrows) match valve. If communication between
between diagnostic jack (2) and control unit and solenoid valve is
plug (1) interrupted or faulty, the control unit
does not initiate an ignition spark.

1 – In the event of a malfunction or if

there is no ignition spark, first
2410RA173 TG

2 check the plug connections and

wiring harness between control
device and solenoid valve
: Remove the plug (1) 1
2410RA215 TG

: Push the plug (1) of the

M-Tronic test lead
5910 840 0903 into the
diagnostic jack (2) as far as it will
go

– After completion of the test

procedure, unplug the test lead
from the diagnostic jack

70 MS 241 C
 Versions with heating All versions

1 1
5

2410RA217 TG
1 4

2410RA219 TG

2410RA221 TG
Screw (1) must be tight. 2

Leads (arrows) must be seated : Remove blade receptacle (1) and Plug (1) must be seated completely
completely and firmly in the blade contact sleeve (2) and firmly in the recess of the
receptacles and the cable lug. solenoid.
: Push out the holder (3) with
ground wire (4) at the air guide : If necessary, remove plug (1) and
shroud (5) and lay it aside check contacts
2 1

Versions with manual fuel pump

1
2

2
2410RA218 TG

3
1

2410RA222 TG
Plug connection (1) must be
pressed together completely –
2410RA220 TG

locking lug (3) must engage the

recess. 3 : Set Master Control lever (1) to
position }; the cam on the
: If necessary. remove the plug lever (2) must actuate the
: Push out the holder (1) with the
connection (1) from the microswitch (arrow) – clicking
fuel pump at the air guide
mount (arrow), remove the sound
shroud (2), remove fuel hose (3)
plug (2) and check the contacts,
at the carburetor (arrow) and lay
b 8.2.3
it on top of the air guide shroud – If the microswitch is not actuated
by the lever at the carburetor,
replace lever if necessary,
b 13.6.6

– If the microswitch does not

function although it was actuated,
then the switchgear must be
replaced, b 8.4

MS 241 C 71
Versions with heating
1
3

2410RA225 TG

2410RA227 TG
2
1
2410RA223 TG

: Push blade receptacle (1) onto : Push the new fuel suction
the connector tab hose (1) completely onto the
: Push the holder (1) with the – Push on blade receptacle all connectors (arrows)
ground wire (2) into the recess in the way
the air guide shroud (3) as far as – Reassemble remaining parts in
it will go : Press lead (2) completely into the reverse order
guide (arrow) of the filter base
: Push ground wire (2) into the
guide (arrow) 8.2.4 Checking the solenoid
Versions with manual fuel pump valve

2 – Carry out test preparations,

b 8.2.1
2
– Check screwed and plug
1 connections, b 8.2.3

– Check contacts and operation,

2410RA224 TG

2410RA226 TG

b 8.2.5
1 3
– Move the Master Control lever to
position "F"
: Push contact sleeve (1) into : Push the holder (1) with the fuel
heating switch pump into the recess in the air
– Push in contact sleeve guide shroud (2) as far as it will – Connect the test lead, b 8.2.2
completely go

: Press lead (2) completely into the : Press fuel return line (3)
guide (arrow) completely into the guide (arrow)

72 MS 241 C
Measuring resistance
1
2
1
1

2410RA222 TG

2410RA166 TG
2 2410RA228 TG
: Set Master Control lever (1) to : Lift retaining tab (arrow) and
position }; the cam on the remove angled plug (1)
: Measure resistance between lever (2) must actuate the
plugs (1) and (2) of the M-Tronic microswitch (arrow) – clicking – Check angled plug, dismantle
test lead sound and clean if necessary, b 7.7.2

Target value: between 28 and – Set Master Control lever to

42 ohms Versions with manual fuel pump position }

– If the target value is not attained, – Push out the holder with the fuel
– Connect the test lead, b 8.2.2
check electrical leads for pump and set it aside, b 8.2.3
interruption, e. g., due to cable
breakage between solenoid
valve and diagnostic jack, or Versions with heating
contact due to damaged
insulation – Disconnect leads, push out the
holder with the heating switch
and set it aside, b 8.2.3
8.2.5 Checking the start
detection function
All versions
– Carry out test preparations,
b 8.2.1

– Check screwed and plug

connections, b 8.2.3
1
2410RA229 TG

: Disconnect the plug (1) from the

solenoid valve (2) – the solenoid
valve must not be twisted; if
necessary, hold the solenoid
valve in place when
disconnecting the plug

MS 241 C 73
 Versions with manual fuel pump Checking the ground connection
2
– Install holder with fuel pump,
push new fuel hose onto
connector and press fuel return 2
line into the guide, b 8.2.3

2410RA230 TG
Versions with heating 1
1 3

2410RA231 TG
– Install holder with heating switch,
press leads in and on and into the
– Connect M-Tronic test lead to
guides, b 8.2.3
multimeter
: Measure the resistance between
– Reassemble remaining parts in blade receptacle (1) with black
: Insert black plug (1) in the "com"
reverse order lead and screw (2) at the control
/ "ground" jack and the red
plug (2) in the "volt" / "ohm" jack unit

8.2.6 Checking the wiring Target value: < 10 ohms.

– Set multimeter to "diode test"
harness

: Test diode on
switchgear (3) (microswitch) in – Carry out test preparations,
2 1
accordance with multimeter b 8.2.1
instruction manual
– Check contacts and operation,
If the switchgear (microswitch) is b 8.2.3
intact and the Master Control lever
is set to the } position, the – Set Master Control lever to

2410RA232 TG
following target values will be position STOP 0
attained:

– Measurement in direction of flow,

target value: 0.3 volts to 0.7 volts : Measure the resistance between
contact spring (1) and screw (2)
– Move the Master Control lever to at the control unit
position F 1
Target value: < 10 ohms.
– Measurement in direction of flow,
required: 1.2 volts to infinity If the target values are not
2410RA166 TG

– Observe display, e.g., (O.L.) attained

or (1.)
– Check electrical leads for
interruption, e. g., cable
– If the required values are not : Lift retaining tab (arrow) and breakage – if necessary, replace
attained, replace switchgear and remove angled plug (1) wiring harness, b 8.2.6
repeat test procedure, b 8.4
– Check angled plug, dismantle
– If the required values are not and clean if necessary, b 7.7.2
attained again, replace wiring
harness; it may be possible to
reuse the previous switchgear,
b 7.7.2

74 MS 241 C
Check leads between control unit – Check continuity between leads Target value: < 10 ohms
and diagnostic jack and blade receptacles
– Blade receptacles must be
– Connect the test lead, b 16 firmly connected to the leads; in
the event of contact problems,
the wiring harness must be
replaced, b 8.2.3, b 8.2.6 1
2

Check leads between solenoid

valve and diagnostic jack

2410RA236 TG
1
– Connect the test lead, b 8.2.2 2
2410RA233 TG

– Versions with manual fuel pump, : Measure the resistance between

remove fuel pump and set it black lead (1) at the plug of the
aside, b 8.2.3 solenoid and red plug (2) of the
: Measure the resistance between diagnostic cable
blade receptacle (1) with red lead
and black plug (2) of the Target value: < 10 ohms
diagnostic cable
If the target values are not
Target value: < 10 ohms. attained
1
– Check contact surfaces on plug
of the plug connection, as well as
2 checking electrical leads for
2410RA229 TG

interruption, e. g., cable

2 breakage

: Disconnect the plug (1) from the – If the contact surfaces on the plug
1
solenoid valve (2) – the solenoid are damaged in the plug
valve must not be twisted; if connection between wiring
2410RA234 TG

necessary, hold the solenoid harness and switchgear, the

valve in place when wiring harness must be replaced,
disconnecting the plug b 7.7.2, if the contacts in the
jack are damaged, the
: Measure the resistance between switchgear must be replaced,
blade receptacle (1) with black b 8.4
lead and red plug (2) of the
diagnostic cable
1 2
– Reassemble remaining parts in
reverse order
Target value: < 10 ohms.

If the target values are not

attained
2410RA235 TG

– Check contact between blade

receptacle of the switch shaft and
contact spring
: Measure the resistance between
red lead (1) at the plug of the
solenoid and black plug (2) of the
diagnostic cable

MS 241 C 75
8.3 Wiring harness Versions with heating All versions

– The M-Tronic leads and the 1 1

ground wire are all combined into
one wiring harness; removal and
installation are described in the
chapter "Short-circuit wire",
b 7.7.2
2

2410RA240 TG

2410RA243 TG
8.4 Switchgear

– Remove shroud, b 6.4

: Remove blade receptacle (1) : Pull plug connector (1) out of the
carburetor support mount (arrow)
– Remove the air filter, b 13.1
: Remove heating element (2)
from the studs
– Check switchgear, b 8.2.5
2 1
– Remove choke rod, b 11.4 Versions with manual fuel pump

– Remove baffle, b 13.2

– Remove filter base, b 13.3

2410RA172 TG
: Hold the jack (1), press the
2410RA241 TG

tab (arrow) and pull out the

1
1 plug (2) – do not tug on the leads

: Disconnect the fuel hose (1)

2410RA239 TG

2
: Pull holder (1) of the switchgear
over the studs (arrows) and lay it
aside
2410RA242 TG

: Push out the holder (1) with the

fuel pump on the air guide
shroud (2) and lay it on top of the
air guide shroud

76 MS 241 C
 1 2 1

2410RA244 TG

2410RA247 TG

2410RA249 TG
3

The fuel hose does not have to be : Pull the wiring harness (1) out of : Orient plug (1) so that the guide
removed from the carburetor the guide (arrow) and pull it out pin (arrow) faces the carburetor
support. between the special bolt (2) and
the starter shaft (3) : Push the plug (1) into the jack of
: Carefully pull out the carburetor the solenoid (2) as far as it will go
with the fuel hose over the studs : Check lever on the starter
and lay it aside – do not shaft (3), replace if necessary,
overextend the fuel hose b 13.6.6
1 2

Installation

With a new switchgear, first the

leads must be inserted in the guides
1 of the switchgear.

2410RA250 TG
Leads and plug connections must
not be damaged.
3
2410RA245 TG

: Orient wiring harness (1) so that

2 the red lead runs underneath the
black lead
: Turn the throttle shaft lever (1)
slightly in the direction of full- 2 1 Choke shutter must be closed.
throttle, then turn the starter
shaft (2) until the choke shutter is
: Guide wiring harness (1)
closed 3
between the special bolt (2) and
the starter shaft (3)
2410RA248 TG

: Press red lead (1) and black

lead (2) completely into the
2 guides (arrows) of the
switchgear (3)
– see illustration
2410RA246 TG

: Disconnect the plug (1) from the

solenoid valve (2) – the solenoid
valve must not be twisted; if
necessary, hold the solenoid
valve in place when
disconnecting the plug

MS 241 C 77
 Versions with manual fuel pump
1 2 1 3 2

2410RA251 TG

2410RA188 TG
2410RA253 TG
: Position the wiring harness (1) so : Orient plug (1) and jack (2) that
that the protective tube (2) rests the tab (3) lines up with the
against the beginning of the : Check seat of the fuel return opening (arrow) – do not twist the
guide line (1), if necessary. press it leads
completely into the
: Press the red and black leads guides (arrows) : Plug connector (1) into jack (2)
completely into the until the tab (3) clicks into place
guides (arrows)
All versions

Versions with heating 2

1

4
1
5

2410RA256 TG
2410RA078 TG

1
2410RA252 TG

: Press the plug connection (1)

2 3 Washer (1) must be fitted. into the mount (2) of the
carburetor support so that the
: Check the lead (1) of the tab (arrow) engages and snaps
thermostatic switch, if necessary, into place in the recess of the
1
press it completely into the plug connection
guides (arrows) on the base of – Plug connection (1) must be
the carburetor and route it behind seated firmly in the mount (2)
the pin (5)
– Push on the carburetor as far as
Plug connectors (2) and (3) and the it will go – pay attention to cable
generator lead (4) must be seated 2 routing and make sure not to
2410RA254 TG

completely in the guides. pinch any leads

Do not remove the fuel hose from

the carburetor support.

: Carefully push the carburetor (1)

with the fuel hose (2) over the
studs (arrows) – do not
overextend the fuel hose

78 MS 241 C
Versions with heating Versions with manual fuel pump All versions

4
2
1
5 1
1

2410RA257 TG

2410RA259 TG

2410RA260 TG
3

: Press thermostatic switch : Push the holder (1) with the fuel : Push the holder (1) of the
lead (1) completely into the pump into the mount of the air switchgear over the studs so that
guide (arrow) of the air guide guide shroud (2) as far as it will the tab rests against the
shroud go; push new fuel hose (3) onto pin (arrow)
– Lead (1) must form a loop at the the connectors (arrows)
plug connection – Install filter base, b 13.3
: Fuel return line (4) must be
seated completely in the – Reassemble remaining parts in
guide (5); if necessary, press the reverse order
3 fuel return line (4) into the
guide (5) again

1
2410RA258 TG

: Slide the heating element (1)

over the studs so that the hole
engages the pin (2)

: Orient the crimped side of the

blade receptacle (3) so that it
faces the carburetor

: Push the blade receptacle (3)

completely onto the connector
tab (arrow)

MS 241 C 79
8.5 Troubleshooting, M-Tronic

8.5.1 Engine does not start

Engine does not start

Can engine yes

– Set Master Control lever be started? Troubleshooting completed
to position }

no
– Test ignition system
according to flow chart
"Ignition system
troubleshooting", b 7.8
no

– Check ignition (spark yes yes

Ignition spark
plug, spark plug boot, Is it possible to start
present?
ignition spark), b 7.4 the engine?

no

– Check start detection,

Mechanically no – Examine switch gear,
(microswitch, actuating
lever), b 8.2.5 OK? clean or replace if
necessary, b 8.2.5
yes

– Examine switch gear and/

– Check start detection and Are target values no or wiring harness, clean or
wiring harness electrically, attained?, b 8.2.5 replace if necessary,
b 8.2.5, b 8.2.6 b 8.2.5, b 8.2.6
yes

Are target values no

– Check solenoid valve, – Replace carburetor,
attained? b 8.2.4 b 13.5
b 8.2.4
yes

– Look for a fault in the fuel

path, check engine for
leaks, b 13.11, b 6.2

80 MS 241 C
8.5.2 Engine does not start in
position }

Engine does not start in

position } – engine floods.
Can the flooded engine be
started in position F? yes
Is it possible to start Troubleshooting completed
the engine?
no

– Check start detection no – Examine switch gear,

Mechanically
(microswitch actuation) clean or replace if
OK?
clean if necessary necessary, b 8.2.5, b 8.4

yes

– Examine switch gear and/

– Check start detection, no or wiring harness, clean or
Are target values
wiring harness and plug replace if necessary,
attained?, b 8.2.5
connections, b 8.2.5, b 8.2.3
b 8.2.5,b 8.2.3
yes

– Look for a fault in the fuel

path (inlet needle, lever,
spring, membrane),
check engine for leaks,
b 13.11, b 6.2

MS 241 C 81
8.5.3 Engine speed drops
under load
– low power

Engine speed drops under load –

low power

– Examine air filter, clean or

replace if necessary, b 13.1

– Calibrate control unit,

b 8.1

yes no
Machine OK?

Troubleshooting completed – Look for a fault in the fuel

path, check engine for
leaks,
b 13.11, b 6.2

82 MS 241 C
8.5.4 Ignition – no ignition
spark

No ignition spark

Can engine yes Troubleshooting

– Set Master Control lever be started? completed
to position }

no

no
– Check the flywheel, Combination Establish correct control unit/
(two pairs of poles?) b 7.6 OK? flywheel combination

yes

Air gap no
– Check air gap between – Set correct air gap, b 7.3
OK?
control unit and flywheel,
b 7.3
yes

– Test ignition system

according to flow chart
"Ignition system
troubleshooting", b 7.8

MS 241 C 83
8.5.5 Engine stops suddenly

Engine stops suddenly Machine yes Troubleshooting

OK? completed

no

– Check fuel path (fuel pick-up no

Fuel path – Repair fuel
body, tank vent, fuel hoses),
OK? system
b 13.11

yes

– Check plug connections,

– Check plug connection on Connection replace wiring harness
no
control unit or between wiring and firm seat of the and/or switching device, if
harness and switchgear plugs OK? necessary b 8.2.3,
b 8.3, b 8.4

yes

– Check start no
Mechanically – Replace switchgear,
detection (microswitch,
OK? b 8.4
actuating lever), clean if
necessary
yes

– Examine switch gear

– Check start detection, wiring no and/or wiring harness,
harness and plug connections, Are target values
attained?, b 8.2.5 clean or replace if
b 8.2.5, b 8.2.6 necessary, b 8.2.5,
b 8.2.6, b 8.3, b 8.4
yes

– Replace carburetor,
Are target values no b 13.5
– Check solenoid valve, attained?, b 8.2.4
b 8.2.4
yes
– Check engine for leaks,
b 6.2

84 MS 241 C
8.5.6 Cut-off speed not
reached

Maximum speed less than

13000 rpm

– Check air filter and spark arrestor screen

(if present) in muffler, clean or replace if
necessary, b 13.1, b 6.1
– Check saw chain tension and chain
lubrication

–Calibrate control unit, Maximum speed yes Troubleshooting

b 8.1 greater than 13000 completed
rpm?

no

Connection no – Check plug, replace

– Check plug connection on and firm seat of the insulating housing or
control unit, b 8.2.3 plug wiring harness if
OK? necessary, b 7.3

yes

– Check start detection, no

Are target values – Replace switchgear,
wiring harness and plug
attained?, b 8.2.5 b 8.4
connections, b 8.2.5
b 8.2.3

yes

– Look for a fault in the fuel

path, check engine for
leaks,
b 13.11, b 6.2

MS 241 C 85
9. Rewind starter

9.1 General 9.2 Fan housing Installation

If the action of the starter rope – Remove shroud, b 6.4 1

becomes very stiff and the rope
rewinds very slowly or not
completely, it may be assumed that
the starter mechanism is in order 1
but plugged with dirt. At very low
outside temperatures, the
lubricating oil on the rewind spring

2310RA203 TG
may thicken and cause the spring
windings to stick together. This has
a detrimental effect on the function

2310RA201 TG
of the starter mechanism. : First insert and position
segment (1) in the slit (arrow) on
To clean the rewind spring, it is the fan housing
sufficient to apply a few drops of a
standard solvent-based degreasant : Remove screw (1) with sleeve
not containing any chlorinated or and screws (arrows)
halogenated hydrocarbons to the 1
rewind spring. – Lift hand guard slightly and
remove fan housing
Carefully pull out the starter rope
several times and allow it to rewind
until its normal smooth action is
restored. 1

2310RA202 TG
Before installing, lubricate the
rewind spring and starter post with 2 2
STIHL special lubricant, b 16.
: Press segment (1) as far as it will
If clogged with dirt or pitch, the go into the pegs (2)
entire starter mechanism, including
2310RA202 TG

the rewind spring, must be removed

and disassembled. Take particular 2 2
care when removing the rewind 1
spring. : Push out segment (1) on the
pegs (2) on the opposite side
– Clean all components through the holes with drift

– Examine fan housing and

Versions with ErgoStart segment, replace if necessary.
2310RA201 TG

– Relieve the tension of the rewind

spring, b 9.4

– Lift hand guard slightly and

position fan housing

: Insert and tighten screw (1) with

sleeve and screws (arrows)

– Reassemble remaining parts in

reverse order

86 MS 241 C
9.3 Pawls Versions with ErgoStart

– Remove ErgoStart, b 9.4

– Remove fan housing, b 9.2

Two pawls are installed in the

– Relieve the tension of the rewind 1 version with ErgoStart. Removal is
spring, b 9.5
the same as with the standard
version.

2310RA206 TG
– Grease the mounts of the new
pawls, b 16
: Position the spring (1) so that the
loop of the spring encloses the – Insert the new pawls and oil the
1 peg of the pawl and the curved pegs of the pawls with resin-free
part of the spring (arrow) is lubricating oil, b 16
located in the groove in the
2310RA204 TG

starter post
Installation
: Then slide the straight part of the
spring over the starter post until it
: Carefully ease the spring (1) off engages in the groove
3
the starter post

– Remove pawl 2

Installation

2310RA208 TG
1

Washer (1) must be fitted.

2310RA207 TG

1
: Position spring (2) so that its
anchor loops engage the pegs of
the pawls and the curved part of
The guide loop of the spring must
the spring (arrow) is located in
2310RA205 TG

run along the pawl (arrow).

the groove of the rope rotor post
Checking correct functioning
: Then slide the straight part (3) of
– Press new pawl into hole (arrow) – Pull starter rope, the rope rotor the spring over the starter post
and grease the peg (1), b 16 turns, and the peg at the pawl until it engages in the groove
moves in the direction of the
anchor loop – the pawl moves – Reassemble remaining parts in
outward reverse order

– Reassemble remaining parts in

reverse order

MS 241 C 87
9.4 ErgoStart Installation Checking correct functioning

The pawls must move freely and

The spring may still have spring
rest against the stop due to the
tension stored in it, thus release the
spring force.
spring tension before any assembly 1
procedure:

– Pull out the starter until the

engine turns – the preloaded 1
spring is relaxed

533RA198 TG
1
– Remove fan housing and, if
necessary, segment, b 9.2
: Install torsion springs in pawls (1)

2310RA210 TG
– observe installation
position (arrows)
2
4 : Push spring housing (1) over the
rope rotor post into the pawls of
the rope rotor (2) – the pawls
must engage in the spring
housing
1
2310RA209 TG

3 2 1
2 1 3 4
5902RA581 TG

: Remove the circlip (1)

2
: Remove washer (2) and
carrier (3) : Push pawls (1) onto the posts (2)
on the flywheel, in the process
pretensioning the torsion springs
: Remove spring housing (4)

2310RA211 TG
and positioning them on the
support ribs (arrow)

: Insert the carrier (1) in the spring

1 housing so that the
1 recess (arrow) engages the
anchor loop (2) of the rewind
spring

1 2 : Fit washer (3)

2710RA165 TG

2710RA274 TG

: Fit the circlip (4)

– Do not overextend circlip
: Push out circlips (arrows)
: Push on the pawls (1) so that – Reassemble remaining parts in
: Pull out pawls (1) and remove they can move towards the reverse order
torsion springs middle of the flywheel as far as
they will go
– Clean the mounts of the
pawls (1), b 16 : Push circlips (2) into place

88 MS 241 C
9.5 Rope rotor – Install pawl or pawls and spring,
b 9.3
Relieve tension of rewind spring
– Install starter rope, b 9.6
The system will not be under 2
tension if the starter rope or rewind 1 – Tension the rewind spring, b 9.7
spring is broken.

2310RA213 TG
– Grease the pegs of the pawl or
– Remove fan housing and pawls, b 16
segment, b 9.2
– Reassemble remaining parts in
Versions with ErgoStart : Remove the washer (1) reverse order
– Remove ErgoStart, b 9.4 The rewind spring must be relieved.
9.6 Starter rope / starter grip
: Carefully pull off the rope rotor (2)
All versions –The rewind spring may pop out – Remove fan housing and
segment, b 9.2
– Examine the rope rotor, replace if
necessary. Versions with ErgoStart

1 2 – Coat the hole in the rope rotor – Remove ErgoStart, b 9.4

with STIHL special lubricant,
b 16 All versions
2310RA212 TG

– Relieve the tension of the rewind

Installation spring, b 9.5

The rewind spring will not be under

: Pull out the starter rope (1) tension if the starter rope is broken.
about 5 cm, then hold the rope
rotor (2) steady – Remove any remaining rope from
the rope rotor if necessary
– Still holding the rope rotor steady,
take three full turns off the rope The starter rope must not be
rotor shortened.
2310RA214 TG

– Pull out the rope with the starter 1

grip and carefully release the
rope rotor : Fit the rotor on the starter post so
that the inner loop of the
– Remove the starter rope; remove spring (arrow) enters the
any remaining scraps of rope, recess (1)
b 9.6
The recess in the hub of the rope
– Remove spring and pawl or rotor acts as carrier for the anchor
pawls, b 9.3 loop.

– Fit the washer.

MS 241 C 89
 1

2310RA215 TG

4903RA132 TG

2310RA218 TG
: Push starter rope (1) out a short Pull the rope through the grip until : Pull starter rope (1) into rotor until
distance and undo the knot the knot at the end of the rope is in the knot rests in the
the recess (arrow) recess (arrow) of the rope rotor
– Pull starter rope out of rope rotor
and fan housing. – Tension the rewind spring, b 9.7

– Reassemble remaining parts in

reverse order

9.7 Tensioning the rewind

1 spring
2310RA216 TG

– Remove fan housing and

segment, b 9.2
165RA227 TG

: Then thread the rope (1) through

the opening (arrow)
: Tie one of the two special knots 2
shown above at the end of the
rope in the starter grip.

1
1
2310RA219 TG
2310RA217 TG

: Pull out part of the starter rope (1)

4903RA131 TG

: Thread starter rope (1) into rope : Turn starter rope (1) with rope
rotor rotor (2) six times clockwise

– Secure the rope (1) with a simple The rewind spring is now tensioned.
: Thread the new starter rope into
the starter grip from above overhand knot
Hold the tensioned rope rotor firmly,
as the rewind spring will be
damaged if it jumps back suddenly.

90 MS 241 C
 When the starter rope is fully Install new rewind spring
1 extended, it must still be possible to
rotate the rope rotor at least
another turn before the maximum 1
spring tension is reached. If not, the
spring tension must be reduced,
otherwise it will break.
2 2

2310RA220 TG
Reduce spring tension
Pull the rope out, hold the rope rotor

2310RA224 TG
steady and take off one turn of the
rope.
: Hold the rope rotor (1) steady
– Reassemble remaining parts in
: Pull out the twisted starter reverse order – Lubricate replacement spring
rope (2) with the starter grip and with frame with a few drops of
straighten it out STIHL special lubricant before
installing it, b 16
9.8 Replacing the rewind
Spring
: Position replacement spring with
2 frame in the fan housing so that
– Troubleshooting, b 3.4 the outer anchor loop (1) is
positioned over the mount for the
The replacement spring is supplied loop (2) and aligns with the
1 ready for installation and secured in mount (arrow)
a spring housing.

– Wear face shield and protective

2310RA221 TG

gloves
– risk of injury

: Hold the starter grip firmly to – Remove fan housing and

keep the rope (1) tensioned segment, b 9.2

: Let go of the rope rotor (2) and let – Relieve the rewind spring if

2310RA226 TG
the starter rope rewind slowly necessary and remove the rope
rotor, b 9.5

– Remove any fragments of the old : Starting at the outer anchor loop,
1 spring push the new rewind spring
through the openings (arrows)
If the rewind spring no longer into the mount of the fan housing
produces sufficient tension, it must – in the process, the frame is
be replaced. removed

A worn rewind spring may still be

2310RA222 TG

under tension while installed.

– Lay a blanket over the assembly

The rewind spring is correctly area and remove the rewind
tensioned when the starter grip (1) spring from the fan housing
sits firmly in the rope guide
bushing (arrow) without drooping to
one side. If this is not the case, the
rewind spring must be tensioned by
one additional turn.

MS 241 C 91
 Reinstalling a rewind spring that Versions with ErgoStart
has popped out Install new rewind spring

If the rewind spring pops out during

installation, fit it in the fan housing 1
as follows:
1
2310RA227 TG

2310RA223 TG
: Press the frame (1) against the
rewind spring and turn it slightly
clockwise until the rewind spring
is completely seated : Check washer (1) and replace if

2310RA230 TG
necessary
The rewind spring may pop out.

– Carefully remove the frame and

keep it – Arrange the rewind spring (1) as
– The frame is reused as an shown in the illustration 1
installation tool for installing
rewind springs that have popped : Insert outer anchor loop in the
out recess (arrow) of the fan housing
2

2310RA225 TG
– Lubricate replacement spring
with frame with a few drops of
1 STIHL special lubricant before
1 installing it, b 16
2310RA228 TG

2310RA231 TG

Position replacement spring with

frame in the fan housing so that the
outer anchor loop (1) is positioned
Make certain that the : Fit the rewind spring (1) in the over the mount for the loop (2) and
rewind spring (1) is inserted spring housing in a circular aligns with the mount (arrow)
completely and the outer anchor fashion, working in clockwise
loop is seated in the anchor loop direction while holding the The further course of action is the
mount (arrow), if necessary, press inserted turns of the spring in same as for "Installing a new rewind
the rewind spring completely into place spring" in versions without
the mount in the fan housing. ErgoStart.
The further course of action is the
– Secure the rewind spring so that same as for "Installing a new rewind
it cannot pop out spring".

– Install the rope rotor, b 9.5

– Reassemble remaining parts in

reverse order

92 MS 241 C
 Reinserting a popped out rewind
spring into the frame

In versions with ErgoStart, the

rewind spring mount sits lower, thus
the rewind spring can only be
1 inserted directly into the fan housing
premounted in a frame.

2310RA229 TG
If the rewind spring pops out during
installation, fit it in the frame as
follows:
Make certain that the rewind
spring (1) is inserted completely
and the outer anchor loop is seated
in the anchor loop mount (arrow), if
necessary, press the rewind spring
completely into the mount in the fan
housing. 1
– Secure the rewind spring so that
it cannot pop out

5902RA608 TG
– Install the rope rotor, b 9.5

– Reassemble remaining parts in

: Insert anchor loop in the
reverse order
recess (arrow) of the frame

: Fit the rewind spring (1) in the

frame in a circular fashion,
working in counterclockwise
direction while holding the
inserted turns of the spring in
place

The further course of action is the

same as for "Installing a new rewind
spring" in versions with ErgoStart.

MS 241 C 93
10. Maintaining the antivibration elements

The front handle / tank housing and

crankcase are connected by 1
vibration-damping springs, rubber
buffers and stop buffers.
2
Damaged springs rubber buffers 2 1
and stop buffers must always be
replaced.

2310RA233 TG

2410RA301 TG
10.1 Antivibration element on
3
oil tank
: Twist out spring (1) with bearing : Push the chain catcher (3) into
plug (2) the mount so that it engages
The antivibration elements are under the bumper strip (2)
located in the area of the oil tank
and are fastened to the bottom of – Inspect spring with plug, replace
if necessary : Screw in the screw (1) and
the machine.
tighten it
– Remove the front handle,
b 10.4, versions with heating, Installation – Reassemble remaining parts in
b 10.4.1 reverse order

2
10.2 Antivibration element on
fuel tank

1
2310RA234 TG

1
1
2410RA300 TG

2 Bearing plug (1) must be twisted

into the spring (2) as far as it will go.

2410RA302 TG
: Remove screw (1)
: Twist spring (2) with bearing
plug (1) into the mount (arrow) as
: Remove the chain catcher (2) far as it will go : Remove screw (1)
– Remove the tank housing, – Install the tank housing,
b 13.11.5 b 13.11.5

94 MS 241 C
Versions with heating Installation

1 2

1
1 3

2310RA237 TG
2410RA303 TG

2310RA239 TG
: Remove cover (1)

: Remove screw (1) on front – Push tank housing down slightly

handle and hold it there

: Orient antivibration element so

All versions that the tab (1) faces the
1 crankcase and push it bearing
plug (2) first between crankcase
and tank housing
1

2310RA238 TG
: Push bearing plug (2) through
the opening

1 2
: Push the antivibration : Push the bearing plug (3) into the
mount (arrow)
2310RA236 TG

element (1) slightly upward and

lift it out of the guide (arrow)

: Remove antiivibration
: Remove screws (1) element (1) between crankcase
and tank housing
: Push tank housing (2) down
slightly and hold it there – Inspect spring and plug, replace if
necessary 1

2310RA240 TG

: Position cover (1) so that it

engages the peg (arrow)
1
2410RA304 TG

: Push front handle out of the

mount (arrow) on the peg (1)
– Do not remove screws on front
handle

MS 241 C 95
 10.3 Antivibration element on
2 front handle

The antivibration element is

1 between front handle and cylinder.

– Remove shroud, b 6.4

1
2410RA304 TG

2410RA306 TG
– Remove the air filter, b 13.1

: Push tank housing upward until : Position bearing stopper (1)

the peg (1) of the front
handle engages in the : Coat screw (2) with Loctite,
mount (arrow) screw in and tighten, b 16
1

Versions with heating

2410RA302 TG
4
1

2 1 : Remove screw (1)

3
2310RA241 TG

– Remove the front handle,

b 10.4
5
2410RA307 TG

: Raise tank housing (1) 2

: Orient bearing plugs (2) and : Position bearing plug (1) and
cover (3) so that the holes align insert and tighten screw (2)
with the hole on the tank housing
– Reassemble remaining parts in
: Screw in and tighten reverse order
screws (5) and (4) 2310RA243 TG

1
2

: Twist out bearing plug (1) and

unhook retainer (arrow)

: Twist out spring (2) and push

retainer (arrow) out of front
handle

– Inspect spring and bearing plug

and retain, replace if necessary

96 MS 241 C
Installation
2

2 1
3
1

2410RA306 TG

0001RA219 TG
2

1 2310RA244 TG : Position bearing plug (1) against : Twist out bearing plug (1) and
cylinder unhook retainer (arrow)
: Push retainer (1) with the small
nipple into the hole in the front : Coat screw (2) with Loctite, : Twist out spring (2) and pull out
handle (2) screw in and tighten, b 16 retainer (arrow)

: Twist spring (3) onto the – Reassemble remaining parts in

peg (arrow) as far as it will go reverse order Installation

10.3.1 Antivibration element on

handlebar, version with
heating
1

1 3
2

5902RA246 TG
2310RA245 TG

1
: Insert retainer (1) with the nipple
: Hook retainer (arrow) onto in the holder (2)
2410RA308 TG

bearing plug (1)

2
: Push bearing plug (1) into the
spring as far as it will go
: Remove screws (1) and (2)

– Install the front handle, b 10.4 : Remove the antivibration

element (3) completely

1
0001RA219 TG

: Twist spring (2) onto the peg

: Hook retainer (arrow) onto

bearing plug (1)

: Twist bearing plug (1) into the

spring (2) as far as it will go

MS 241 C 97
 – Replace stop buffer 10.3.3 Filter base buffers
3 1
– Remove filter base, b 13.3
Installation

2410RA309 TG
1

: Position antivibration element (1)

2
against front handle and cylinder

2410RA311 TG

2310RA249 TG
: Screw in the screw (2) and 1
tighten it
– Orient the stop buffer (1) on both : Remove screw (1)
: Coat screw (3) with Loctite, sides – the conical pegs (arrow)
screw in and tighten, b 16 facing the crankcase
: Push tank housing (2) down
slightly and hold it there
– Reassemble remaining parts in – To simplify installation, coat the
reverse order conical pegs with STIHL press
fluid, b 16
1 1
10.3.2 Stop buffer : Press the stop buffers (1) with the
pegs on the inside of the
crankcase completely into holes
The stop buffers are installed – to simplify assembly, twist the
between crankcase and tank stop buffers while pressing them
housing on the ignition and clutch in
side.

2410RA313 TG
– Remove the tank housing,
b 13.11.5
: Press out the buffers (1) on the
underside (arrows)

– Check buffers (1) and replace if

necessary
2410RA312 TG
2410RA310 TG

The conical pegs must enclose the

holes completely.
1
– Reassemble remaining parts in
: Pry out stop buffers (1) on the reverse order
ignition and clutch sides

98 MS 241 C
Installation : Lift front handle (1) slightly at the
side and remove it from the
2 guide (arrow).
1 1

1 1 1 2

2310RA253 TG
2410RA314 TG
: Push tank housing (1) upward
and hold it there

2310RA157 TG
: Orient buffers (1)
– conical pegs facing the : Screw in the screw (2) and
holes (arrows) tighten it
: Remove screws (1) on the
– To simplify installation, coat the – Reassemble remaining parts in underside of the machine and lift
conical pegs with STIHL press reverse order front handle (2) out of the
fluid, b 16 mount (arrow)

: Press the buffers (1) with the 10.4 Front handle

conical pegs completely into the
holes (arrows) –to simplify
assembly, twist the buffers while – Remove shroud, b 6.4
pressing them in 1

0001RA232 TG
1

: Remove front handle (1) from the

2410RA302 TG

lower guide
2410RA315 TG

– Remove and examine front

handle (1), replace if necessary
: Remove screw (1)
The conical pegs (arrows) must – Examine the antivibration spring
enclose the holes completely on the and replace if necessary, b 10.3
reverse.

1
2410RA315 TG

– Take out screws

MS 241 C 99
Installation
2 1
– Position front handle

1
1

2410RA306 TG

2410RA303 TG
2
: Position bearing plug (1) of the : Remove screw (1) on front
antivibration spring against handle
2310RA158 TG

cylinder

: Coat screw (2) with Loctite,

: Lift front handle (1) with the screw in and tighten, b 16 1 1 2
peg (2) facing forward into the
recess (arrow) until it is seated in – Reassemble remaining parts in
the mount of the tank housing reverse order

– Insert and tighten down

the screws 10.4.1 Handlebar with heating

2310RA157 TG
As the front handle is heated in
these machines, the wiring must
also be disconnected for : Remove screws (1) on front
2 installation. handle (2) on the underside of
the machine
1 – Troubleshooting, b 14.7.1

– Remove shroud, b 6.4

2410RA317 TG

– Remove handle molding, trigger

interlock and throttle trigger, 1
b 11.2
: Lift the front handle (1) somewhat
at the side and place it in the
guide (arrow) so that the peg (2)
2410RA557 TG

engages in the mount of the

crankcase
1
– Insert and tighten down the : Remove screw (1)
screws 2
2310RA167 TG

: Pull throttle rod (1) out of the

mount (arrow) and unhook it from
the throttle trigger (2)

100 MS 241 C
 1 4

1 1

2410RA319 TG

2410RA323 TG

0001RA240 TG
2 3 5

: Press pegs (1) out of the : Push insulating tube (1) toward : Remove front handle (1) from the
mount (arrow) and lower front the wiring harness and push lower guide
handle (2) with tank housing insulating tube (2) toward the
front handle heating element – Remove front handle

Do not disconnect plug

connection (3).
2
: Disconnect plug connections (4)
and (5)
2
1
1
2410RA321 TG

2410RA325 TG
: Unscrew screw (1) and remove 1
cover (2) : Unscrew screw (1) while pushing
1 down the plastic sleeve (2)
2410RA320 TG

– Remove plastic sleeve

: Remove screws (1)

1
3
2
2410RA322 TG

2 1
1
2410RA326 TG

: Pull plug connections (1), (2)

and (3) with insulating tubes out
of the guides
2410RA324 TG

: Remove the handle insert (1)

– Examine the front handle

: Lift front handle (1) at the side
heating, replace front handle if
and remove the cover (2) from
necessary
the mount
b 14.6

MS 241 C 101
Installation
1 2
– Press the plug connection
together completely, b 1 1

2410RA329 TG

2410RA330 TG
The leads on the front handle are of Do not pinch the leads and plugs.
different lengths; during assembly,
1 take care that the short lead (1) is : Lift front handle (1) slightly and
2410RA327 TG

connected to the lead to the heating push the cover (2) into the mount
switch and the long lead (2) is
connected to the lead to the handle : Push the front handle (1) into the
: Press in the handle insert (1) as heating element. mount (arrow)
far as it will go
– Position front handle

2
2
1

3
1 2 1

2410RA335 TG
2410RA328 TG

2310RA158 TG

: Orient the leads of the front

: Screw in the screw (1) and handle in the guide (arrow) so
tighten it : Lift front handle (1) with the that the long lead (1) runs
peg (2) facing forward into the underneath the short lead (2)
recess (arrow) until it is seated in
: Push on plastic sleeve (2) until it
the mount of the tank housing
snaps into place The wiring harness and the
connecting leads must be located
– Insert screws – do not tighten underneath the throttle rod (3).

102 MS 241 C
 1 3 2 1

2410RA332 TG

2410RA334 TG

2410RA337 TG
: Insert and tighten screws (1) – : Push insulating tube (1) onto Plug connection with shorter lead of
lines must be seated in the thick lead of the handle heating the front handle.
guide (arrow)
: Push connector (2) with long lead : Press insulating tube (1) with
– Tighten screws of the front completely into the terminal plug connection as far as it will go
handle on the underside of the socket (3) into the guide (arrow)
machine
– Push insulating tube entirely over
the plug connection
1
1 3 2 – Lift tank housing slightly

2410RA338 TG
2410RA333 TG

– Lift the tank housing again and

: Push insulating tube (1) onto hold it there
2410RA336 TG

lead of the heating switch

: Press insulating tube (1) with
: Push connector (2) with short plug connection as far as it will go
lead completely into the terminal into the guide (arrow)
Plug connection with longer lead of
socket (3) the front handle.

– Push insulating tube entirely over : Position insulating tube (1) with
the plug connection plug connection at the edge of
the tank housing and push it into
the guide (arrow) as far as it will
go

MS 241 C 103
 1
2

2 1
2410RA339 TG

2410RA341 TG

2310RA253 TG
: Run the thin lead (1) with a The leads of the handle heating : Push tank housing (1) upward
loop (2) around the rib and press element must be seated completely and hold it there
it into the guide (arrow) as far as in the guide (arrow).
it will go : Screw in the screw (2) and
– Install throttle trigger, b 11.2 tighten it

– Reassemble remaining parts in

reverse order
3
2 1
2
2
2410RA340 TG

2310RA167 TG

: Orient cover (1) so that the

pegs (2) engage the holes and : Hook throttle rod (1) onto throttle
the tab (3) engages the trigger (2) and press it into the
fin (arrows) guide (arrow)

– Replace cover, insert and tighten – Install trigger interlock and

screw handle molding, b 11.2
– Ensure that wires are not
pinched

104 MS 241 C
11. Actuating levers

11.1 Master Control lever – Examine the filter base, replace if

necessary 2
The positions of the Master Control
lever are described in the
Instruction Manual. Installation
1
– Position filter base in the
11.1.1 Removal and installation carburetor space

2310RA164 TG
– Remove the air filter, b 13.1

– Remove choke rod, b 11.4 : Press the switch shaft (1) onto
the post (2) of the filter base as
far as it will go
– Remove the filter base from the
studs, b 13.1
– Install contact spring, b 7.7.4
– Remove contact spring, b 7.7.4 1

2310RA162 TG
2
: Position switch shaft (1) in
carburetor space

– Install ground wire on the switch

1 shaft, b 7.7

2310RA155 TG
2310RA160 TG

1 : Check correct functioning

– Blade receptacle of the ground
: Turn the switch shaft (1) wire must touch the contact
counterclockwise as far as it will spring (arrow) in position "0"
go and pull it of off the shaft (2) of
the filter base
– Reassemble remaining parts in
reverse order
2410RA343 TG

: Orient the switch shaft (1) so that

the inserted ground wire faces
the filter base and the
opening (arrow) lines up with the
rib (2)
1
2310RA161 TG

– Disconnect ground wire at the

switch shaft, b 7.7

: Take out and examine the switch

shaft (1), replace if necessary

MS 241 C 105
11.2 Throttle trigger / throttle
trigger interlock 3 2
1

1 2

2310RA170 TG
2310RA167 TG
5902RA307 TG

: Pull throttle rod (1) out of the : Insert throttle trigger (1) into the
1 mount (arrow) and unhook it from handle so that the tab (arrow) is
the throttle trigger (2) inside the handle and the holes
on the throttle trigger and handle
: To disassemble the handle
align
molding. press the pegs (1) on
the underside apart and through
the rear hand guard 2 : Center the throttle trigger (1) with
4 punch (2)
1
In version with heating, the
1 connecting leads must be routed
entirely in the guide and must not
3 protrude
2310RA168 TG

– Risk of leads becoming pinched,

b 14.9.

: Drive in the pin (3) until it is

: Push out pin (1) with drift (2)
2310RA165 TG

equidistant on both sides

: Remove throttle trigger (3) with

torsion spring (4)
: Remove handle molding (1)
– Examine trigger interlock, throttle 1
The trigger interlock (arrow) may trigger and torsion springs,
pop out. replace if necessary
2

Installation
2310RA171 TG

1
: Hook the throttle rod (1) onto the
throttle trigger (2) and hook it into
1 the guide (arrow)
2
2310RA166 TG

Make certain that the torsion spring

2310RA169 TG

is hooked entirely into the throttle

trigger.
: Pull the trigger interlock (1) out of
the bearing points (arrows)
: Hook the torsion spring (1) into
the throttle trigger (2)
– Note the installed
position (arrow)

106 MS 241 C
 – Check correct functioning
2
1
– Reassemble remaining parts in
reverse order 2

11.3 Throttle trigger / throttle

trigger interlock /

2310RA172 TG

2310RA176 TG
QuickStop Super
1
After each removal, coat sliding and
: Press end (1) of the torsion bearing points with grease. : Pull throttle rod (1) out of the
spring toward the handle mount (arrow) and unhook it from
the throttle trigger (2)
: Press the trigger interlock (2) into
the bearing points (arrow) 1

5902RA307 TG
1

2310RA177 TG
: To disassemble the handle 1
2310RA173 TG

molding. press the pegs (1) on

1 the underside apart and through : Push out pin (1) with drift (2)
the rear hand guard
: Hook the torsion spring (1) onto
the trigger interlock (arrow)
1
The trigger interlock may pop out.
1
2

2310RA178 TG
2310RA175 TG

: Remove throttle trigger (1) with

: Remove handle molding (1) torsion spring (2)
2310RA174 TG

1 2 – Check rotor on throttle trigger to

ensure that it can be rotated,
: Hook handle molding (1) with the replace throttle trigger if
tabs (2) into the openings (arrow) necessary

– Fit handle molding (1) until it – Examine the torsion spring and
snaps into place replace it if necessary

MS 241 C 107
Installation – Carefully fit handle molding (1)
3 1 2 until it snaps into place

– Check correct functioning

– Reassemble remaining parts in

2 1 reverse order

2310RA182 TG
2310RA179 TG

11.3.1 Trigger switch

QuickStop Super
: Center the throttle trigger (1) with
punch (2)
After each removal, coat sliding and
: Hook the torsion spring (1) into
bearing points with grease.
the throttle trigger (2) : Drive in the pin (3) until it is
– Note the installed equidistant on both sides – Remove handle molding, b 11.3
position (arrow)

1
2
1
2310RA183 TG

2310RA184 TG
2310RA180 TG

1
: Hook the throttle rod (1) onto the : Push out pin (arrow) with drift (1)
: Insert throttle trigger (1) in the throttle trigger (2) and hook it into
handle so that the angled end of the guide (arrow)
the torsion spring engages in the
mount (arrow) and the holes on
– Grease rotor on throttle trigger,
the throttle trigger and handle
align
b 16 2

1
1
2310RA185 TG

: Partly remove switch lever (1)

2310RA174 TG

and turn by approx. 90°, then pull

2310RA181 TG

off brake cable (2)

1 2
– Examine switch lever, replace if
: Hook handle molding (1) with the necessary
The brake cable (1) must lie
tabs (2) into the openings (arrow)
completely in the guide (arrows)
and be underneath the drift – do not
damage the brake cable. – Press trigger interlock
downwards

108 MS 241 C
Installation 11.3.2 Trigger interlock Installation
QuickStop Super

After each removal, coat sliding and

bearing points with grease.
1
– Remove handle molding, b 11.3 1
2

2310RA186 TG

2310RA190 TG
2

: Hook brake cable (1) into : Align torsion spring (1) and insert
hole (arrow) in switch lever in trigger interlock

: Turn switch lever (2) until it faces : Slide bushing (2) into

2310RA188 TG
upwards hole (arrow) – torsion spring is
1 secured

: Push out pin (arrow) with drift (1)

3 1
– Remove trigger interlock
2310RA187 TG

2310RA191 TG
2
2 3 1 2
: Center the throttle trigger (1) with
punch (2) Torsion spring (arrow) must rest
2310RA189 TG

against the tank housing.

: Drive in the pin (3) until it is 1
equidistant on both sides : Center trigger interlock (1) with
drift (2)
: Drive out bushing (1)
– Reassemble remaining parts in
reverse order : Drive in the pin (3) until it is
: Remove torsion spring (2) equidistant on both sides
– Check function of the switch lever
– Examine trigger interlock, throttle – Reassemble remaining parts in
by actuating the trigger interlock
trigger and bushing, replace if reverse order
necessary
– Check correct functioning

MS 241 C 109
11.4 Choke rod
1
– Remove the air filter, b 13.1

1 2

3 2

2410RA345 TG

2310RA293 TG
2
: Insert choke rod (1) in : Pry out throttle rod (1) at the
1 guide (arrow) carburetor support (2)
2410RA344 TG

: Move switch shaft (2) to position

"F" and hold it there, then press
choke rod (1) completely into the
: Move switch shaft (1) to position
mount (arrow)
"F" and pry out choke rod (2) at
the mount (arrow)
– Check correct functioning 1
: Unhook the choke rod (2) from
the lever (3) The choke rod must be completely
snapped into place.

2310RA294 TG
– Examine choke rod and replace it
– Reassemble remaining parts in
if necessary
reverse order
: Guide throttle rod (1) through the
opening (arrow) in the direction
Installation
11.5 Throttle rod of the control handle and remove
it
2 – Remove handle molding and
trigger interlock, b 11.2, – Examine the throttle rod and
QuickStop Super, b 11.3 replace it if necessary

– Remove choke rod, b 11.4

Installation
– Remove baffle, b 13.2
2410RA331 TG

1 – Remove filter base and set it

aside, b 13.3
: Hook choke rod (1) into
hole (arrow) in the starter – Carefully pull out the carburetor
shaft (2) over the studs and lay it aside 1
– Do not overextend fuel hose,
2310RA295 TG

b 8.4

: Guide throttle rod (1) between

tank housing and crankcase
through the opening (arrow) in
the direction of the carburetor
support

110 MS 241 C
 1

2310RA296 TG
: Press the throttle rod (1) into the
guide (2) on the carburetor
support until it snaps into place

– Install handle molding and trigger

interlock, b 11.2, QuickStop
Super, b 11.3

– Push carburetor with attached

fuel hose onto the studs, b 8.4

– Install filter base, b 13.3

– Check correct functioning

– when the throttle trigger is
actuated, the throttle trigger must
move upwards at the carburetor

– Reassemble remaining parts in

reverse order

MS 241 C 111
12. Chain lubrication

12.1 Pickup body 12.2 Oil suction hose : Orient oil suction hose (1) so that
the straight sides (arrows) rest
Impurities gradually clog the fine against the crankcase
– Unscrew oil tank cap and drain oil
pores of the filter with minute tank, b 1
particles of dirt. This prevents the oil : Push in oil suction hose (1) until
pump from supplying sufficient oil to the groove is completely flush
– Remove the clutch, b 4.2
the bar and chain. Always check the with the hole in the crankcase
oil tank and pick-up body first if
– Remove brake band, b 5.2
problems develop in the oil supply. – Check position of pick-up body,
clear it with the aid of assembly
– Troubleshooting, b 3.3 – Remove oil pump, b 12.3 hook 5910 893 8800 if necessary

– Unscrew oil tank cap and drain oil – Install oil pump, b 12.3
tank
– Reassemble remaining parts in
– Collect oil in a clean container, reverse order
b1

– Clean the oil tank if necessary, 1 12.3 Oil pump

b 16

2410RA346 TG
– Troubleshooting, b 3.3

1 – Remove the clutch, b 4.2

: Pry out oil suction hose (1) and
pull it out with pickup body – Remove brake band, b 5.2

– Examine oil suction hose and

pick-up body, replace if
necessary
2
219RA457 TG

TOP
– Fit the pickup body, b 12.1
1
: Pull pick-up body (1) out of oil
tank with assembly hook (2) Installation
5910 893 8800 2410RA348 TG

Take care not to overextend the

suction hose.
: Remove the washer (1)
– Pull off pickup body (1) and
1
examine it, replace if necessary
2410RA347 TG

– Reassemble parts in reverse

order

– Coat groove of oil suction hose

with STIHL press fluid, b 16

: Push oil suction hose (1) through

opening in housing with the pick-
up body first

112 MS 241 C
 2
1 1
1
2
2

2410RA349 TG

2410RA352 TG

2410RA355 TG
: Pull worm (1) with spring (2) out : Remove sealing ring (1) : Push in oil pump (1) as far as it
of oil pump will go
– Examine oil pump, replace if
– Inspect spring and worm, replace necessary : Screw in screws (2)
if necessary and tighten them

Installation – Push the worm home until it

makes contact

1 1
2 TOP

1
2410RA350 TG

2410RA353 TG

2410RA356 TG
: Unscrew screw (1) and remove
cover (2) : Push new sealing ring (1) into the
opening (arrow)
: Slide on the washer (1)

It has been fitted correctly when the

4 1
1 word "TOP" (arrow) is visible.
5
2 – Reassemble remaining parts in
reverse order
1 3
2
2410RA351 TG

2410RA354 TG

: Remove screws (1)

: Orient oil pump (1) so that the
: Pull oil pump (2) out of the oil connector (2) engages in the oil
suction hose and remove it suction hose (3) and the
connector (4) slides into the
sealing ring (5)

– Coat connectors and sealing ring

with STIHL press fluid, b 16

MS 241 C 113
12.4 Valve Installation

A valve is installed in the tank wall to

keep internal tank pressure equal to
atmospheric pressure. The valve
must be replaced if faulty. 1
– Unscrew oil tank cap and drain oil
tank, b 1

2410RA318 TG
Ensure that the parts are installed
correctly.

: Insert valve (1) into hole (arrow)

in crankcase
2410RA342 TG

– Carefully drive valve into hole in

engine housing from the outside
with a Ø 6 mm drift – observe the
insertion depth
: From the outside, carefully drive
the valve out of the case in the
direction of the inside of the tank
with a Ø 6 mm drift
219RA479 TG
219RA476 TG

: Drive new valve into the hole

1 a = 1 mm +/- 0.1

: Remove old valve (1) from oil – Reassemble remaining parts in

tank reverse order

114 MS 241 C
13. Fuel system

13.1 Air filter 13.2 Baffle

Dirty air filters reduce engine power, – Remove the air filter, b 13.1
2
increase fuel consumption and
make starting more difficult. The air
filter should be checked when there
is a noticeable loss of engine power.

2410RA237 TG
– Refer also to troubleshooting,
b 3.6, b 3.7 1
1
– Remove shroud, b 6.4 : Push buffer (1) out from under
the pin of the filter base (2)

2410RA263 TG
: Unscrew the nuts (arrows)
1 1
: Remove baffle (1)

– Examine baffle, replace if

2410RA255 TG

necessary.

2410RA264 TG
– Reassemble parts in reverse
order
: Turn the air filter (1)
counterclockwise and remove it : Remove filter base (1) from the
studs (arrows)
13.3 Filter base
– Examine air filter, clean or
replace if necessary
– see Instruction Manual – Remove the air filter, b 13.1

– Remove choke rod, b 11.4

1
– Reassemble parts in reverse
order
– Remove baffle, b 13.2

2410RA238 TG
Versions with heating

: Pull the filter base (1) out of the

buffer (2)

1
2410RA169 TG

: Remove lead (1) from cable

guide (arrow)

MS 241 C 115
 Installation

– Position filter base in the

carburetor space
1
2 1
– Install switch shaft, b 11.1

– Install contact spring, b 7.7.4

2410RA268 TG
2410RA265 TG

: Remove short circuit wire (1) and : Press filter base (1) over the
contact spring (2) from the 2 studs (arrows) onto the
guides (arrows) carburetor

– Remove contact spring, b 7.7.4

3
– Remove switch shaft, b 11.1

2410RA261 TG
2
– Remove filter base 1

– Use STIHL press fluid to improve

assembly, b 16
1 1

2410RA269 TG
: Push the pin (1) of the filter
base (2) into the hole in the 1
ignition side buffer (3) as far as it
will go – Use STIHL press fluid to improve
assembly, b 16
2410RA266 TG

: Push the buffer (1) completely

over the pins of the filter base (2)
1
– the shoulder of the pin must
protrude completely from the
: Check buffer (1), replace if
opposite side of the buffer
necessary, b 10.3.3 3
– Install the choke rod, b 11.4
2410RA267 TG

: Orient the filter base (1) so that

the pin (2) is below the tab (3)

116 MS 241 C
 Versions with heating
2 1

1 1

2410RA270 TG

2410RA172 TG
2

2410RA169 TG
: Use wiring tool 5910 890 4000 to : Hold the jack (1), press the
press the ground wire (1) into the tab (arrow) and pull out the
guides (arrows) so that it lies : Insert lead (1) completely in plug (2) – do not tug on the leads
snug against the air guide shroud cable guide (arrow)
and the marking (2) is at the edge – Remove the carburetor, b 13.5
of the guide – Reassemble remaining parts in
reverse order – Remove the throttle rod, b 11.5

– Remove carburetor support,

13.4 Air guide shroud b 13.8

– Remove shroud, b 6.4

– Remove fan housing, b 9.2

1
2410RA271 TG

2 – Remove filter base

– Do not remove contact spring
and switch shaft, b 8.4
1
: Use wiring tool 5910 890 4000 to

2410RA272 TG
press the short-circuit wire (1) – Unplug the spark plug boot
into the guides (arrows) so that it
lies snug against the air guide
shroud and the marking (2) is at
the edge of the guide : Remove the plug (1)

– Check the switching functions of

the switch shaft
1
2
2410RA171 TG

1
2410RA273 TG

: Pull plug connector (1) out of the

carburetor support mount (arrow)

: Remove diagnostic jack (1) with

bushing (2) from the
guides (arrows)

MS 241 C 117
 1
1

2410RA274 TG

2410RA277 TG

2410RA280 TG
1 2

: Pry out and remove the cable : Press the grommet (arrow) of the : Pull the air guide shroud (1) over
holder (1) at the pin (arrow) fuel hose (1) downward and out the buffers and out of the mounts,
in the process, pushing the fuel
hose (2) through the hole (arrow)

1
2

1
1
2
2410RA275 TG

2410RA278 TG

2410RA281 TG
: Remove grommet (1) and wiring : Press tab (1) in the direction of
harness from the guides (arrows) the clutch side and pry the air
guide shroud (2) out of the mount : Press the manifold flange (1) out
– Lay aside the wiring harness with of the air guide shroud (2) by
the filter base hand in the direction of the
cylinder while pulling of the air
guide shroud
2
1 1 – Pull the fuel hose out of the air
guide shroud
1
– Remove the air guide shroud
2410RA279 TG

– Replace fuel hose, b 13.11.2

2410RA276 TG

: Press tab (1) in the direction of

the ignition side and pry the air
: Remove screws (1) guide shroud (2) out of the mount

118 MS 241 C
Installation : Pull the grommet of the fuel
hose (2) into the hole (arrow) in
the air guide shroud (1) until the
grommet entirely encloses the
hole

2410RA284 TG
1 2410RA282 TG
: Push new fuel hose (1) through 1
the opening (arrow)
– Pull out the shutter and inspect it,
replace if necessary

2410RA287 TG
: Slide the shutter (1) into the 2
guide until it snaps into place
: Orient the grommet (1) of the fuel
1
hose (2) so the the straight
3 side (arrow) rests against the
edge of the air guide shroud
2

2410RA285 TG
2

1 : Pull the manifold flange (1)

1
through the opening by the ends
2410RA283 TG

of the string (2), at the same time

pressing the air guide shroud (3)
2
against the manifold flange

2410RA288 TG
: To pull the manifold flange (2)
into the hole of the air guide – Remove the string
shroud, place a string (1) that is 2
approx. 15 cm long around the
manifold flange Shown without piston and cylinder
for a better view.
– To simplify assembly, coat the
manifold flange with The lugs (2) of the air guide
STIHL press fluid, b 16 1 shroud (1) must engage the
mounts (arrows) of the crankcase.
2
2410RA286 TG

– To simplify installation, coat the

grommet with STIHL press fluid,
b 16

MS 241 C 119
 – Remove the throttle rod, b 11.5
1
1 – Remove carburetor support,
b 13.8

2410RA289 TG 1

2410RA292 TG
2 2 2

: Guide the air guide shroud (1) : Push the grommet (1) into the
over the buffers (2) and push the mount until it is flush with the
lugs into the mounts of the edge of the air guide shroud

2410RA293 TG
crankcase
– Install wiring harness in the air
guide shroud, b 7.7.2
: Remove fuel return line (1) at the
1 – Install the carburetor, b 13.5 fuel pump (2) and pull it out of the
guides (arrows)
– Install the filter base with the
attached wiring harness, b 8.4
2
1 1
– Reassemble remaining parts in
2410RA290 TG

reverse order

13.4.1 Air guide shroud,

: Press the air guide shroud (1) versions with manual fuel
into the mount until the tab (2) pump

2410RA294 TG
snaps into place

– Remove shroud, b 6.4

: Remove screws (1)

– Remove fan housing, b 9.2
1
– Remove filter base
– Do not remove contact spring
2 and switch shaft, b 8.4

– Unplug the spark plug boot

2410RA291 TG

– Remove wiring harness from the

air guide shroud and lay it aside
2410RA295 TG

: Press the air guide shroud (1) with the filter base, b 7.7.2
into the mount until the tab (2) 1
snaps into place – Remove the carburetor, b 13.5
: Press the grommet (arrow) of the
– Install the carburetor support, fuel hose (1) downward and out
b 13.8

– Install the throttle rod, b 11.5

120 MS 241 C
 Installation
2
2
1

2410RA296 TG

2410RA299 TG

2410RA442 TG
: Press tab (1) in the direction of : Pull fuel hose (1) and fuel return 1
the clutch side and pry the air line (2) out of the air guide shroud
guide shroud (2) out of the mount – Pull out the shutter and inspect it,
– Remove the air guide shroud replace if necessary

: Slide the shutter (1) into the

2 guide until it snaps into place

1
1
2410RA297 TG

1
2410RA538 TG

: Press tab (1) in the direction of

2410RA443 TG
the ignition side and pry the air : Ease out grommet (1) and
guide shroud (2) out of the mount examine it, replace if necessary

– Replace fuel hose, b 13.11.2 – To simplify installation, coat the

outside of the grommet with
STIHL press fluid, b 16
– Replace fuel return line and fuel
suction hose, b 13.11.3
1 : Press grommet (1) into
hole (arrow) until it encloses the
: Examine fuel pump and replace if
2 hole completely
necessary, b 13.11.4
2410RA298 TG

: Press the manifold flange (1) out

of the air guide shroud (2) by
hand in the direction of the
cylinder while pulling the air guide
shroud out of the mounts

MS 241 C 121
 2 1
1
3
1
2410RA283 TG 2

2410RA445 TG

2410RA447 TG
2

: To pull the manifold flange (2) : Pull the manifold flange (1) : Orient the grommet (1) of the fuel
into the hole of the air guide through the opening by the ends hose (2) so the the straight
shroud, place a string (1) that is of the string (2), at the same time side (arrow) rests against the
approx. 15 cm long around the pressing the air guide shroud (3) edge of the air guide shroud
manifold flange against the manifold flange

– To simplify assembly, coat the – Remove the string

manifold flange with
STIHL press fluid, b 16

2
1

2410RA448 TG
3
2
4
2410RA446 TG

2 1 : Pull in the new fuel return line (1)

completely through the
2410RA444 TG

grommet (2)
– To simplify installation, coat the
grommet with STIHL press fluid,
: Fit the air guide shroud (1) b 16

: Push new fuel hose (2) through : Position the air guide shroud (1) 1
the opening (arrow) and pull the grommet of the fuel
hose (2) into the hole (arrow)
– Use STIHL press fluid to simplify until the grommet completely
encloses the hole 2
assembly, b 16
2410RA288 TG

: Push the new fuel return line (3)

completely through the 2
grommet (4)
Shown without piston and cylinder
for a better view.

The lugs (2) of the air guide

shroud (1) must engage the
mounts (arrows) of the crankcase.

122 MS 241 C
 1
1
1

2410RA449 TG

2410RA452 TG

2410RA292 TG
2 2

: Guide the air guide shroud (1) : Orient the fuel return line (1) so : Push the grommet (1) into the
over the buffers (2) and push the that the marking (arrow) is mount until it is flush with the
lugs into the mounts of the located at the grommet (2) edge of the air guide shroud
crankcase
– Install wiring harness in the air
guide shroud, b 7.7.2
1
1 – Install the filter base with the
3 attached wiring harness, b 8.4

– Reassemble remaining parts in

2 reverse order

2410RA453 TG
2
2410RA450 TG

13.4.2 Air guide shroud version

with heating
: Starting at the grommet (2),
: Press the air guide shroud (1) press the fuel return line (1) into
– Remove shroud, b 6.4
into the mount until the tab (2) the guides (arrows) – the
snaps into place marking (3) must be located at
the upper guide rib – Remove fan housing, b 9.2

– Route the fuel return line so that – Remove filter base

it is snug – the fuel return line – Do not remove contact spring
1 must not form a loop between the and switch shaft, b 8.4
air guide shroud and the
grommet – Unplug the spark plug boot
2
– Install the carburetor support, – Remove wiring harness from the
b 13.8 air guide shroud and lay it aside
2410RA451 TG

with the filter base, b 7.7.2

– Install the throttle rod, b 11.5
– Remove the carburetor, b 13.5
: Press the air guide shroud (1) – Install the manual fuel pump,
into the mount until the tab (2) b 13.11.4 – Remove carburetor support,
snaps into place b 13.8
The fuel return line must not be
kinked or pinched.

– Install the carburetor, b 13.5

MS 241 C 123
 1 1
2

2410RA454 TG

2410RA457 TG

2410RA460 TG
2

: Pull contact sleeve (1) out of : Slide insulating tube (1) towards : Press tab (1) in the direction of
heating switch (2) generator and disconnect plug the clutch side and pry the air
connection guide shroud (2) out of the mount

3 3
2
1

1
2410RA455 TG

2410RA458 TG

2410RA461 TG
1 2
: Remove lead (1) from the
guides (arrows) : Pull insulating tube (1) off of the : Press tab (1) in the direction of
generator lead (2) the ignition side and pry the air
guide shroud (2) out of the mount
: Remove screws (3)

2 1
2
2410RA456 TG

1
2410RA462 TG
2410RA459 TG

: Remove plug connection with

insulating tube (2) and generator 1
lead (1) from the guides (arrows) : Press the manifold flange (1) out
: Press the grommet (arrow) of the of the air guide shroud (2) by
fuel hose (1) downward and out hand in the direction of the
cylinder while pulling the air guide
shroud out of the mounts

124 MS 241 C
 Installation
2

1 1

2410RA463 TG

2410RA465 TG

2410RA467 TG
: Press out the grommet (1) of the : Ease out grommet (1) and 1
generator lead (2) in the direction examine it, replace if necessary
of the generator and pull the – Pull out the shutter and inspect it,
generator lead (2) out of the replace if necessary
hole (arrow)
: Slide the shutter (1) into the
– Pull the grommet off of the guide until it snaps into place
generator lead – to make it 2
easier, twist the grommet while
pulling it off 1

2410RA466 TG
1
2
: Remove ground wire (1) from the
3
guide (arrow)

2410RA468 TG
: Push the holder (2) with the
2410RA464 TG

heating switch out of the mount

1 – To simplify installation, coat the
– Examine heating switch and outside of the grommet with
replace if necessary, b 14.4 STIHL press fluid, b 16
: Pull the fuel hose (1) out of the air
guide shroud : Press grommet (1) into
– Examine ground wire and
replace if necessary, b 14.4 hole (arrow) until it encloses the
: Pull the wiring harness (2) out of hole completely
the air guide shroud through the
– Replace fuel hose, b 13.11.2
grommet (3)

– Remove air guide shroud with

heating switch and ground wire

MS 241 C 125
 – To simplify assembly, coat the
manifold flange with
STIHL press fluid, b 16

2410RA469 TG

2410RA473 TG
1
1 2 2
2
: Push grommet (1) onto the The crimped side of the ground
generator lead (2) so that the wire (2) must face the intake elbow.

2410RA286 TG
conical area (arrow) faces the
generator – to make it easier, : Press holder (1) with heating
twist the grommet while pushing switch as far as it will go into the
it on : Fit the air guide shroud (1) guides (arrows)

: Push new fuel hose (2) through

the opening (arrow)
1 4
6
5 1
1
3 2
2410RA413 TG

2410RA474 TG
2
2410RA472 TG

The generator lead (1) must be : Push lead (1) with terminal
seated completely in the socket (2) through the right
guide (arrow). hole (see illustration) of the
grommet (3) and pull it in until the
– To simplify installation of the
connector (4) has been pulled
grommet, coat the outside of the
through the grommet (3)
grommet with STIHL press fluid,
b 16
: Push lead (5) with terminal
2 : Push the generator lead (1)
socket (6) through the left
hole (see illustration) of the
through the hole on the
grommet (3)
1 side (arrow) and press the
grommet (2) into the hole until it
2410RA471 TG

completely encloses the hole

: To pull the manifold flange (2)

into the hole of the air guide
shroud, place a string (1) that is
approx. 15 cm long around the
manifold flange

126 MS 241 C
 : Position the air guide shroud (1)
and pull the grommet of the fuel
hose (2) into the hole (arrow)
until the grommet completely
encloses the hole
2

2410RA475 TG

2410RA479 TG
1 1
2 1 2

: Pull in wiring harness (1) until the : Guide the air guide shroud (1)
protective tube (2) rests against over the buffers (2) and push the
the grommet lugs into the mounts of the
crankcase

2410RA478 TG
2

: Orient the grommet (1) of the fuel 1

hose (2) so the the straight
1
side (arrow) rests against the
edge of the air guide shroud
3
2
2
2410RA476 TG

2410RA480 TG
1
: Pull the manifold flange (1)
through the opening by the ends : Press the air guide shroud (1)
of the string (2), at the same time into the mount until the tab (2)
2
pressing the air guide shroud (3) snaps into place
against the manifold flange
2410RA288 TG

– Remove the string 2

Shown without piston and cylinder 1

for a better view.

The lugs (2) of the air guide 2

1 shroud (1) must engage the
mounts (arrows) of the crankcase.
2410RA481 TG
2410RA477 TG

: Press the air guide shroud (1)

2 into the mount until the tab (2)
snaps into place
– To simplify installation, coat the
grommet with STIHL press fluid,
b 16

MS 241 C 127
 4 1 2 1 2 3 1
5

2410RA482 TG

2410RA484 TG

2410RA486 TG
4 2

: Pull in generator lead (1) and : Push together the connector (1) : Push the contact sleeve (1) into
wiring harness (2) and the terminal socket (2) the heating switch (2) as far as it
will go
: Position cable lug (3) so that the : Slide insulating tube (3) over the
crimped side faces upward and plug connection
insert screws (4)

: Push ground wire (5) into the

guide (arrow) and tighten 1
screws (4)

– Press the plug connections 2

together completely, b 1

2410RA487 TG
1
2410RA485 TG

3 : Press the lead (1) completely into

the guides (arrows) so that it
: Press the plug connection with rests snug against the air guide
1 insulating tube (1) into the center shroud
of the guide
3 The generator lead must be routed
: Route the generator lead (2) in along the lower guide below the
2410RA483 TG

the guides (arrows) so that it lies lead of the heating switch.

2 snug against the air guide shroud
and forms a loop (3) at the – Install the carburetor support,
insulating tube (1) b 13.8
: Route generator lead (1) behind
the wiring harness (2)
– Install the throttle rod, b 11.5
: Slide insulating tube (3) over the
generator lead (1) – Install the carburetor, b 13.5

128 MS 241 C
 All versions
1
1
1

2410RA292 TG

2410RA239 TG

2410RA243 TG
: Push the grommet (1) into the : Pull holder (1) of the switchgear
mount until it is flush with the over the studs (arrows) and lay it
edge of the air guide shroud aside : Pull plug connector (1) out of the
carburetor support mount (arrow)
– Install wiring harness in the air
guide shroud, b 7.7.2 Versions with manual fuel pump

– Install the filter base with the

2 1
attached wiring harness, b 8.4

– Reassemble remaining parts in

reverse order

2410RA172 TG
2410RA241 TG
13.5 Carburetor

1
– Pull off the filter base over the
: Hold the jack (1), press the
studs and lay it aside with the
: Disconnect the fuel hose (1) tab (arrow) and pull out the
attached wiring harness, b 8.4
plug (2) – do not tug on the leads

– Open filler cap and drain fuel tank

2 Version with heating
– Collect fuel in a clean container,
b1
1
The fuel hose may only be removed
when the tank filler cap is open.
2410RA242 TG

1 2
2410RA240 TG

: Push out the holder (1) with the

fuel pump on the air guide
shroud (2) and lay it on top of the
air guide shroud : Remove blade receptacle (1)

: Remove heating element (2)

from the studs

MS 241 C 129
 All versions – Examine the carburetor and
repair or replace it if necessary,
b 13.5, b 13.6
2
– Replace fuel hose, b 13.11.2

Versions with manual fuel pump

2410RA470 TG

– Replace fuel suction hose,

1 b 13.11.3

2410RA488 TG
: Pull off carburetor (1) slightly and 1
pull lead (2) out of the Installation
guide (arrow) : Disconnect the fuel hose (1) from
the connector (arrow). Versions with manual fuel pump

2410RA493 TG
2410RA488 TG

2410RA491 TG

1
1 2
: Disconnect the fuel hose (1) from : Check seat of the fuel return
the connector (arrow). : Pull off carburetor (1) with line (1), if necessary. press it
switchgear (2) completely into the
guides (arrows)
– Remove switchgear at the
2 carburetor, b 8.4
Versions with heating

1
2
2410RA489 TG

1
4 1 3
2410RA494 TG

: Pull insulating tube (1) with plug

2410RA492 TG

connection out of the

3 2
guide (arrow), slide insulating
tube (1) in direction of the
thermostatic switch and : Check seat of the heating switch
: Check ring (1) and sealing
disconnect plug connection lead (1) and generator lead (2), if
ring (2) and replace if necessary
necessary. press completely into
the guides (arrows)
: Pull off carburetor (2) with : Check connector (3) – in case of
switchgear (3) and thermostatic a damaged connector (3), the
switch (4) carburetor must be replaced

130 MS 241 C
All versions : Push together the connector (3)
2 and the terminal socket (4)

1 : Slide the insulating tube (1) over

the plug connection, if necessary,
with gentle twisting motions

2410RA497 TG
1
2410RA495 TG
: Push new fuel hose (1) onto the
connector (2) so that the
Washer (1) must be fitted. tab (arrow) faces the throttle
shaft lever and fits against the
1
connector evenly

2410RA416 TG
2 Version with heating
: Press the plug connection with
1 – Press the plug connection insulating tube (1) into the center
together completely, b 1 of the guide (arrow)
2410RA492 TG

3
1

Ring (1) must be in place.

2
Sealing ring (2) must be in place.
1
Connector (3) must engage in the
2410RA498 TG

2410RA503 TG
hole of the manifold flange.

– Install the switchgear wiring 2

harness on the carburetor, b 8.4
: The lead (1) of the thermostatic The lead (1) of the thermostatic
switch must be seated in the switch must run along the loop (2)
guides (arrows) and run behind above the generator lead.
the stud (2)
: Press lead (1) completely into the
guide (arrow)

4
2410RA496 TG

3
1
1
2410RA499 TG

: Slide on the carburetor (1) over 2

the studs (arrows) until it is flush
with the studs
: Push insulating tube (1) onto
lead (2) of the thermostatic
switch

MS 241 C 131
All versions Versions with manual fuel pump
1 2
1 4
2

5 1

2410RA505 TG
2410RA504 TG

2410RA259 TG
: Press the plug connection (1) 3
into the mount (2) of the
: Push on the carburetor (1) further carburetor support so that the : Push the holder (1) with the fuel
tab (arrow) engages and snaps pump into the mount of the air
into place in the recess of the guide shroud (2) as far as it will
plug connection go; push new fuel hose (3) onto
1 3 2 - Plug connection (1) must be the connectors (arrows)
seated firmly in the mount (2)
: Fuel return line (4) must be
– Push on the carburetor as far as seated completely in the
it will go – pay attention to cable guide (5); if necessary, press the
routing and make sure not to fuel return line (4) into the
pinch any leads guide (5) again
2410RA188 TG

Versions with heating

: Orient plug (1) and jack (2) that
the tab (3) lines up with the 3
opening (arrow) – do not twist the
leads

: Plug connector (1) into jack (2) 2

until the tab (3) clicks into place
1
2410RA258 TG

: Slide the heating element (1)

over the studs so that the hole
engages the pin (2)

: Orient the crimped side of the

blade receptacle (3) so that it
faces the carburetor

: Push the blade receptacle (3)

completely onto the connector
tab (arrow)

132 MS 241 C
All versions 2. The inlet valve is not sealing
1 (foreign objects in the valve
seat,
sealing cone of the inlet needle
is damaged or
inlet control lever is sticking),
1 remove to clean,
b 13.1

2410RA506 TG
2 3. Pump diaphragm or

2410RA260 TG
gasket damaged,
replace if necessary, b 13.6.3
: Push the fuel line (1)
1110 141 8600 onto the double – Check tank vent if necessary,
: Push the holder (1) of the connector (2) 0000 855 9200 b 13.10.1
switchgear over the studs so that
the tab rests against the : Push the fuel line with double – After completing the test, slide
pin (arrow) connector onto the fuel ring (1) to the left and vent the
port (arrow) system, then disconnect fuel line
– Install the filter base with the from elbow connector of
attached wiring harness, b 8.4 carburetor

– Install the choke rod, b 11.4 2 – Install the carburetor, b 13.5

– Install air filter, b 13.1 – Install the filter base with the
attached wiring harness, b 8.4
– Check correct functioning
– Set throttle trigger to full – Reassemble remaining parts in
throttle; the throttle shutter on the
2410RA507 TG

reverse order
carburetor must be open all the
way 1
13.6 Repairing the carburetor
– Reassemble remaining parts in – Push the delivery hose of the
reverse order pump 0000 850 1300 onto the
double connector All versions are controlled by the
M-Tronic system, thus no adjusting
screws are required or present on
13.5.1 Leakage test : Push ring (1) to the right and
the carburetor. Solenoid and special
pump air into the carburetor until
bolt for idle stop may not be
the pressure gauge (2) shows a
The tank vent must also be checked modified or removed; if they are
pressure of approx. 0.8
and replaced if problems develop damaged, the carburetor must be
bar (80 kPa)
with the carburetor or fuel supply, replaced.
b 13.10
If this pressure remains constant,
The carburetor can be tested for the carburetor is airtight. However, if
leaks with the pump the pressure drops, this may have
0000 850 1300. the following causes:

– Remove filter base with attached 1. Metering diaphragm or gasket is

wiring harness and lay it aside, damaged, replace if necessary,
b 8.4 b 13.6.1

– Remove the carburetor, b 13.5

MS 241 C 133
13.6.1 Metering diaphragm
2 1 2 1
2
– Troubleshooting, b 3.6
2
– Remove the carburetor, b 13.5 2

2310RA256 TG

2410RA359 TG
3
1
: Carefully separate the metering : Orient the end cover (1) so that
diaphragm (1) and gasket (2) the connector (3) faces the choke
shutter and the holes align
The diaphragm material is
2410RA357 TG

subjected to continuous alternating : Fit and screw in the screws (2) –

stresses and eventually shows do not tighten them
signs of fatigue. In other words, the
diaphragm distorts and swells and – Check that the metering
: Take out the screws (arrows) must be replaced. diaphragm and gasket are
correctly seated, then tighten
: Remove the end cover (1) – Examine the metering diaphragm down the screws crosswise
for signs of damage and wear, fit
If the gasket and diaphragm are a new gasket
The sealing ring (arrow) must not be
stuck to the carburetor, they must damaged.
be removed very carefully.
Installation – Reassemble remaining parts in
reverse order

1
2
2
2410RA371 TG

2410RA358 TG

: Check sealing ring (1) and – Note the order in which the
replace if necessary metering diaphragm (1) and
gasket (2) are installed
– For versions with manual fuel
pump, check connector (2), : Align the gasket (2) and metering
replace end cover if necessary diaphragm (1) so that the small
holes on the tabs engage the
pins (arrows)

134 MS 241 C
13.6.2 Inlet needle Ensure that the spring locates on
the nipple of the inlet control lever.
– Remove the metering
diaphragm, – Press the inlet control lever down
and secure it with the screw.
b 13.6.1

– Check that the inlet control lever

moves easily

165RA348 TG
1
– Install the metering diaphragm,
b 13.6.1
3 : The inlet needle must be
replaced if a circular
indentation (arrow) is visible on 13.6.3 Pump diaphragm
the tip of its sealing cone
2410RA372 TG

– Troubleshooting, b 3.6
2
Installation
– Remove the carburetor, b 13.5
: Remove screw (1)

: Pull the inlet control lever (2) with

spindle (3) out of the groove in 1
the inlet needle

The spring under the inlet control 1 2

lever may pop out.
2410RA361 TG 2

2410RA375 TG
: Fit the inlet needle (1)

: Remove screw (1)

: Fit spring (2) in bore

1 2 : Remove the end cover (2)

2410RA360 TG

2 If the gasket and pump diaphragm

are stuck to the carburetor, they
must be removed very carefully.
: Pull out the inlet needle (1) 1

: Take out and examine the

spring (2), replace if necessary
2410RA373 TG

: First fit the spindle (2) of the inlet

control lever (3) at the conical
seat (arrow) of the spring, then
slide the clevis on the inlet control
lever into the groove on the inlet
needle (1)

MS 241 C 135
Version with handle and – Examine the pump diaphragm for
carburetor heating signs of damage and wear, fit a
new gasket

1 – Examine fuel strainer for

contamination and damage,
clean or replace if necessary
2 3

2410RA363 TG
1
1
2410RA362 TG

– Position the end cover (1) on the

carburetor housing from below so
that the gasket and pump
: Remove screw (1) diaphragm remain secured to the
end cover
: Remove thermostatic switch (2)

2310RA267 TG
: Orient the end cover (1) so that
: Remove the end cover (3) the protrusion (arrow) faces the
lever of the throttle and choke
: Pull fuel strainer (1) with needle shaft
If the gasket and pump diaphragm
are stuck to the carburetor, they out of the carburetor housing and
must be removed very carefully. clean or replace it
Version with heating
– Reassemble parts in reverse
All versions order
3

2 Installation
2 1

1 2

2410RA364 TG
2310RA266 TG

1
4
: Move the end cover (1) back and
3 forth slightly until the pegs on the
2310RA268 TG

– Carefully remove the pump end cover engage in the holes in

diaphragm with gasket from the 4 the carburetor housing
end cover
: Position gasket (1) and pump : Position the thermostatic
: Carefully separate the pump diaphragm (2) on the end switch (2) so that it rests against
diaphragm (2) and gasket (1) cover (3) so that the the raised part (arrow)
– always use a new gasket protrusions (arrows) match and
are secured in the pins (4) – Check that the pump diaphragm
The diaphragm material is and gasket are correctly seated
subjected to continuous alternating
stresses and eventually shows : Screw in the screw (3) and
signs of fatigue. In other words, the tighten it
diaphragm distorts and swells and
must be replaced.

136 MS 241 C
 1 2 3 1 1

2
2

2410RA367 TG
2410RA374 TG

2410RA365 TG
: Press lead (1) into the : Remove screw (1) and pull out : Press out the circlip (1) and
guides (arrows) so that is is cable holder (2) remove the lever (2)
behind the peg (2)

: Slide on the insulating tube (3) Installation Installation

All versions 2 3 4

1
2

2410RA368 TG
2410RA366 TG
1 2
2410RA376 TG

: Orient the cable holder (1) so that : Orient lever (1) so that the hook
the closed side faces the engages the lever of the choke
carburetor and the pin lines up shaft (arrows)
– Move the end cover (1) back and with the mount (arrow)
forth slightly until the pegs on the : Slide the lever (1) onto the
end cover engage in the holes in : Press in the cable (1) as far as it throttle shutter shaft (2) so that it
the carburetor housing will go aligns with the flat faces

– Check that the pump diaphragm : Screw in the screw (2) and : Push circlip (3) into place
and gasket are correctly seated tighten it
: Check correct functioning
: Screw in the screw (2) and – Install the wiring harness with – Lever (1) must engage in
tighten it switchgear, b 8.4 lever (4) (arrows)

– Reassemble remaining parts in – Reassemble remaining parts in – Reassemble remaining parts in

reverse order reverse order reverse order

13.6.4 Lead retainer 13.6.5 Lever of the throttle shaft

– Remove the carburetor, b 13.5 – Remove the carburetor, b 13.5

– Remove the wiring harness with – Troubleshoot carburetor, b 3.6

switchgear, b 8.4

MS 241 C 137
13.6.6 Lever of the choke shaft – Install carburetor, check correct 13.8 Carburetor bracket
functioning
– Lever (1) must actuate the
– Remove the carburetor, b 13.5 – Remove filter base with attached
microswitch, b 13.5, b 8.2.5
wiring harness and lay it aside,
– Troubleshoot carburetor, b 3.6 b 8.4
– Reassemble remaining parts in
reverse order
– Remove switchgear and
carburetor and lay them aside,
1 b 8.4
13.7 Carburetor adjustment

The carburetor is adjusted by the

2 M-Tronic, thus no manual
adjustments to the carburetor are
necessary or possible.
1
2410RA369 TG

2410RA508 TG
: Push out circlip (1)

: Remove lever (2)

2
: Remove the washer (1)
Installation
2410RA377 TG

1 1

2 Position of the special bolt (1) must

not be changed
– changing the factory default
1 setting leads to impaired engine
performance.
3

2410RA509 TG
2410RA370 TG

Solenoid valve (2) must not be

dismantled.
: Orient lever (1) so that it faces : Pull throttle rod (1) out of the
The solenoid valve must not be guide (arrow) and set it aside
the throttle shaft and the flat twisted when disconnecting the
face (arrow) faces the solenoid plug; if necessary, hold the solenoid
valve valve in place during disconnection
of the plug.
: Slide the lever (1) onto the choke
shaft (2) so that it aligns with the If the solenoid valve is twisted, twist
flat faces of the choke shaft it back clockwise as far as it will go.

: Push circlip (3) into place – In case of malfunctions, check

M-Tronic, b 8.2

138 MS 241 C
 3
2 2
1 1

2410RA510 TG

2410RA512 TG

2410RA514 TG
: Press the manifold flange (1) out – Coat manifold flange with STIHL The hole (arrow) of the intake
of the carburetor support (2) by press fluid, b 16 elbow (1) must be unobstructed;
hand in the direction of the clean if necessary – a fouled hole
cylinder while pulling off the : Pull the manifold flange (2) can lead to impaired engine
carburetor support through the opening by the ends performance, b 3.7.
of the string (1), at the same time
– Remove carburetor support, pressing the carburetor
check it and replace if necessary support (3) against the manifold Versions with manual fuel pump
flange
– Examine intake elbow, replace if 1
necessary, b 13.9 – Remove the string

Installation

2410RA426 TG
1
2
2
: Check seat of the fuel return
2410RA513 TG

1 2 line (1), if necessary. press it

completely into the
2410RA511 TG

guides (arrows)

: Orient the carburetor support (1)

so that the openings (arrows)
: To pull the manifold flange (2) rest against the studs (2)
into the hole of the carburetor
support, place a string (1) that is
approx. 15 cm long around the
manifold flange

MS 241 C 139
Versions with heating 13.9 Intake elbow

1 A damaged intake elbow may lead

to impaired engine performance.

– Troubleshooting, b 3.7

2410RA548 TG
2410RA427 TG
– Remove shroud, b 6.4

– Remove the carburetor, b 13.5

: Examine and clean the mating

– Remove carburetor support,
surfaces (arrows), b 16
b 13.8
: Check seat of the lead (1) to the
heating switch; if necessary. The mating surfaces must be in
press it completely into the – Remove the air guide shroud,
perfect condition and without any
guides (arrows) b 13.4
damage whatsoever. Parts with
Versions with manual fuel pump,
damaged mating surfaces must be
b 13.4.1,
replaced.
Versions with heating, b 13.4.2
1

2
1
2410RA509 TG

2310RA359 TG
2410RA547 TG

: Press the throttle rod (1) into the 1

guide (arrow) until it clicks into
place. : The hole (1) of the intake
: Take out the screws (arrows) elbow (2) must be unobstructed;
clean if necessary – a fouled hole
: Remove intake elbow (1) can lead to impaired engine
performance
– Examine intake elbow and
replace if necessary. The
1 slightest damage may lead to
impaired engine performance,
b 13.9
2410RA515 TG

: Slide on the washer (1)

– Reassemble remaining parts in

reverse order

140 MS 241 C
Installation Pressure is equalized via the tank
vent. A negative pressure must not
build up inside the fuel tank.

– Clean the area around the tank

vent

1 – Replace the tank vent or tank

2410RA558 TG
housing if necessary, b 13.10 or
1 b 13.11.5

2410RA549 TG
: Push the connector (1)
0000 855 9200 into the fuel Testing with gauge pressure
: Position intake elbow (1) against hose (arrow)
cylinder
2
: Insert and tighten down the Versions with manual fuel pump
screws (arrows)

1
– Install air guide shroud, b 13.4
Versions with manual fuel pump,

2410RA518 TG
b 13.4.1,
Versions with heating, b 13.4.2
2 1
– Install the carburetor support,
b 13.8 2410RA516 TG : Slide ring (1) to the right and
connect the pump (2)
0000 850 1300 to the double
– Reassemble remaining parts in
nipple (arrow)
reverse order
– Create excess pressure in fuel
: Close fuel suction hose (1) with a
tank
suitable stopper (2)
13.10 Tank vent
– Actuate the pump until the
13.10.1 Testing pressure gauge shows a
Testing with negative pressure
pressure of 0.5 bar. If this
If problems develop in the pressure remains constant for at
carburetor or fuel supply, the tank 2 least 20 seconds, the tank and
vent must always also be tested and tank vent are airtight. If the
replaced if necessary. Correct pressure drops, the leak must be
functioning is determined by testing located and the defective part
the fuel tank under vacuum or at replaced.
gauge pressure via the fuel hose.
– Reassemble parts in reverse
2410RA517 TG

– Open filler cap and drain fuel order

tank, b 1
1
– Close the filler cap
: Slide ring (1) to the left and
connect the pump (2)
– Remove the carburetor, b 13.5 0000 850 1300 to the double
nipple (arrow)
– Create vacuum in fuel tank

MS 241 C 141
13.10.2 Removal and installation

– Remove shroud, b 6.4

1

2310RA368 TG

2310RA370 TG
1 : Pry out the tank vent (1) via the : Remove wooden assembly block
mounting rib (arrow) and raise tank housing (1) until
2310RA365 TG

the holes (arrow) in tank housing,

Always fit a new tank vent. cover and antivibration spring
align
: Remove screw (1) – Wet O-ring of new tank vent with
STIHL press fluid, b 16

– Press the new tank vent in by

1 hand until it audibly engages

2 1

2310RA365 TG
1
2310RA366 TG

: Screw in the screw (1) and

tighten it
2310RA369 TG

: Press tank housing (1)

downward and maintain spacing
by inserting wooden assembly – Reassemble remaining parts in
reverse order
block (2) 1108 893 4800
: Position cover (1) so that it
engages the peg (arrow)

1
2310RA367 TG

: Remove cover (1)

142 MS 241 C
13.11 Fuel intake
13.11.1 Pickup body

Impurities which are entrained into

the fuel tank with the fuel are
1
trapped by the pick-up body. With 1
time, the fine pores in the pick-up

2310RA371 TG

2310RA372 TG
body become clogged with very fine
dirt particles. This reduces the
intake diameter and fuel can no
longer be delivered in sufficient
quantities. : Use hook 5910 893 8800 to pull : Remove screw (1)
the pickup body (1) out of the fuel
Always check the fuel tank and pick- tank
up body first if problems develop in
the fuel supply. Take care not to overextend the fuel
hose.
– Troubleshooting, b 3.6 or
b 3.7 – Pull off pickup body (1) and 1
examine it, replace if necessary
Clean the fuel tank if necessary.
– Reassemble parts in reverse

2410RA302 TG
– Open the filler cap and drain the order
tank.

– Fill a little clean gasoline into the 13.11.2 Fuel hose : Remove screw (1)
tank, close the tank and shake it
thoroughly.
– Open the filler cap
Versions with heating
– Reopen the tank and empty it
– Remove the pickup body,
b 13.11.1
– Ensure that the fuel is disposed 1
of correctly and without harming
– Remove the carburetor, b 13.5
the environment, b 1

– Remove carburetor support,

– Open the filler cap
b 13.8

2410RA303 TG
– Remove the air guide shroud,
b 13.4
Versions with heating, b 13.4.2

: Remove screw (1) on front

handle

MS 241 C 143
Versions with QuickStop Super

2 1
1 1

2310RA378 TG

2410RA522 TG
2310RA057 TG

: Remove connector (1) from fuel – Use STIHL press fluid to simplify
hose (2) assembly, b 16
Before lowering the tank housing,
loosen the brake cable holder, – Remove the pickup body, : Orient the fuel suction hose (1)
because the sleeve of the brake b 13.11.1 and press it into the hole in the
cable can be pulled out of the housing as far as it will go – the
adjusting screw when the tank flange must be flush with the
housing is lowered guide (arrow)
– Brake cable adjustment can be
negatively affected.

: Unscrew screw (1) pull

support (2) out of the mount 1

1
2410RA520 TG

All versions 2
– Lower the tank housing

2310RA382 TG
: Pull the fuel suction hose (1) out
of the inside of the tank

– Replace fuel hose and fuel : Orient the flat surface of the
suction hose; check connector, connector (1) so that it faces the
replace if necessary tab of the fuel hose (2) (arrows) –
1 tab must rest evenly against the
connector
Installation
2410RA519 TG

: Push the connector (1) into the

fuel hose (2) as far as it will go

: Pull out fuel hose (1) with

connector
1
2410RA521 TG

: Push fuel suction hose (1) into

hole (arrow) in fuel tank

144 MS 241 C
 Versions with QuickStop Super

2
2
1
2 1
1

2410RA523 TG

2310RA525 TG

2310RA059 TG
: Push fuel hose (1) with the : Orient the fuel hose (1) so that it
connector (2) in front into the fuel is underneath the brake cable (2)
suction hose so that it is between in accordance with the illustration : Press brake cable holder with the
the ribs (arrows) and runs toward the ignition side pin (1) through the opening and
into the mount (arrow)

Versions with QuickStop Super All versions : Screw in the screw (2) and
tighten it

1 2

1
2
1
2410RA524 TG

2310RA387 TG

2410RA306 TG
: Push fuel hose (1) with the : Insert antivibration spring (1)
connector (2) in front under the through the opening (arrow)
brake cable and into the fuel : Fit the plug (1) of the antivibration
suction hose so that it is between : Raise tank housing (2) spring
the ribs (arrows)
– Insert and tighten down the screw : Screw in the screw (2) and
tighten it

MS 241 C 145
Versions with heating – Install the carburetor support, Versions with QuickStop Super
b 13.8

1 2
– Install the carburetor, b 13.5

– Close the filler cap

1
– Reassemble remaining parts in
reverse order
2410RA307 TG

2310RA057 TG
2
13.11.3 Fuel hoses manual fuel
pump
: Fit the plug (1) of the antivibration Before lowering the tank housing,
spring on the front handle loosen the brake cable holder,
– Open the filler cap because the sleeve of the brake
: Screw in the screw (2) and cable can be pulled out of the
tighten it – Remove the pickup body, adjusting screw when the tank
b 13.11.1 housing is lowered
– Brake cable adjustment can be
– Check position of the fuel hose
– Remove filter base, b 13.3 negatively affected.
and correct it if necessary,
b 13.11.2
: Unscrew screw (1) pull
support (2) out of the mount

1
1
2410RA527 TG
2410RA526 TG

2410RA528 TG
: Disconnect the fuel suction
: Use hook 5910 893 8800 to pull hose (1) from the
the fuel suction hose (1) out of connectors (arrows)
: Remove fuel hose (1),
the fuel tank
b 13.11.2
– Remove the carburetor, b 13.5
Take care not to overextend the fuel
suction hose. – Remove carburetor support,
b 13.8
– Fit the pickup body, b 16
– Remove the air guide shroud,
– Install air guide shroud, b 13.4 b 13.4.1
Versions with heating, b 13.4.2
– Lower the tank housing,
b 13.11.2

146 MS 241 C
 2
1
1
1

2410RA529 TG

2410RA530 TG

2310RA399 TG
2

: Pull out connector (1) with fuel : Remove fuel suction hose (1), : Push the connector (1) into the
return line (2) b 13.11.2 fuel return line (2) as far as it will
go

Installation
Versions with QuickStop Super

2
1 3
2
1
1
2310RA393 TG

2410RA551 TG

2410RA553 TG
: Remove connector (1) from fuel
return line (2) 4
: Install fuel suction hose (1),
b 13.11.2 : Guide the fuel return line (1)
connector-first under the brake
cable (2)

: Guide the connector (3) with the

fuel return line (1) between the
1 1 ribs (arrows) and push it into
grommet (4)
2410RA550 TG

2410RA552 TG

: Pry out grommet (1)

– Replace fuel return line, check – Use STIHL press fluid to simplify
connectors and grommet and assembly, b 16
replace if necessary
: Press grommet (1) into
hole (arrow) of the fuel tank until
it encloses the hole completely

MS 241 C 147
 13.11.4 Manual fuel pump
1 2
2
– Remove shroud, b 6.4
1

2
2410RA554 TG

2410RA531 TG
5 3 4

Fuel return line (1) must be : Push the new fuel return line (1)
underneath the brake cable (2) and into the long connector (2) as far

2410RA533 TG
run around the brake cable in as it will go
accordance with the illustration.
1
: Push the new fuel suction
hose (3) onto the short
: Disconnect the fuel suction
connector (4) and the
hose (1) and fuel return line (2)
connector (5) on the carburetor
from the connectors (arrows)
1 as far as it will go
– Replace fuel hoses, b 13.11.3
– Check correct functioning
– Fuel must be drawn in when the
fuel pump is actuated
2410RA555 TG

1 2

1
: Install fuel hose (1), b 13.11.2

– Install air guide shroud,

2410RA534 TG
b 13.4.1

– Install the carburetor support,

2410RA532 TG

b 13.8
: Push holder (1) with fuel
pump (2) out of the
– Install the carburetor, b 13.5
guides (arrows) of the air guide
: Press fuel return line (1)
shroud
completely into the guide (arrow)

– Check proper functioning with

manual fuel pump, b 13.11.4

– Reassemble remaining parts in

reverse order

148 MS 241 C
 13.11.5 Tank housing
1 1 2
– Empty the fuel tank, b 1

– Remove the front handle,

b 10.4
Versions with heating, b 10.4.1

2410RA535 TG

2410RA537 TG
– Remove the carburetor, b 13.5

– Remove carburetor support,

: Press the lugs (arrows) together : Push holder (1) with fuel
b 13.8
and push out the fuel pump (1) pump (2) as far as it will go into
the guides (arrows) of the air
guide shroud – Remove the air guide shroud,
– Examine fuel pump and replace
b 13.4
if necessary
Versions with manual fuel pump,
b 13.4.1,
1 2 Versions with heating, b 13.4.2
Installation
– Versions with QuickStop Super,
unhook brake cable at brake
lever, b 5.4

– Remove actuating lever, b 11

2410RA531 TG

5 3 4
2410RA536 TG

: Push the fuel return hose (1) onto

2 3 1 the long connector (2) as far as it
will go 1
: Orient fuel pump (1) so that the
tab (3) faces the recess (arrow) : Push the fuel suction hose (3)
onto the short connector (4) and

2410RA557 TG
: Press fuel pump (1) into the connector (5) on the
holder (2) until the lugs engage carburetor as far as it will go

– Check correct functioning

– Fuel must be drawn in when the : Remove screw (1)
fuel pump is actuated

– Reassemble remaining parts in

reverse order

MS 241 C 149
 All versions
3
– Examine the tank housing and
replace it if necessary.
2
1 Those parts of the old tank housing
which are not supplied with the new 1
2410RA300 TG tank housing must be reused – see

2310RA414 TG
spare parts list.
2
– Replace fuel hoses
: Remove screw (1) : Press antivibration spring (1) into
the bearing seat (2) so that the
: Remove the chain catcher (2) tab (3) engages in the
opening (arrow)

2410RA540 TG
2 2
1 1 1
2310RA410 TG

: Check stop buffers (1) on the

2410RA301 TG
ignition and clutch sides, replace
if necessary, b 10.3.2 3
: Pry antivibration spring (1) out of
the bearing seat (2) : Push the chain catcher (3) into
Installation the mount so that it engages
under the bumper strip (3)
1
1 : Screw in the screw (1) and
tighten it
2410RA541 TG
2410RA539 TG

2
2
: Guide tank housing (1) with the
: Pull tank housing (1) out of the narrow part (2) in front into the
crankcase (2) mount in the crankcase

Versions with QuickStop Super

– Pull out the tank housing, at the

same time pulling the brake cable
out of the crankcase

150 MS 241 C
Versions with QuickStop Super All versions
2
– Install air guide shroud, b 13.4
3 Versions with manual fuel pump,
b 13.4.1, 1
4 Versions with heating, b 13.4.2

2310RA417 TG
2

2410RA542 TG
1
: Raise tank housing (2)

: Push the brake cable (1) with the : Screw in the screw (1) and
short hook (4) in front past the tighten it
right side of the fuel hose (3) and

2310RA416 TG
through the opening (arrow)
– Install the front handle, b 10.4
Versions with heating, b 10.4.1
Versions with manual fuel pump
: Insert antivibration spring (1)
– Versions with QuickStop Super,
: Push the brake cable (1) with the through the opening (arrow) in
hook on brake cable at brake
short hook (4) in front past the the crankcase
lever, b 5.4
right side of the fuel hose (3) and
the fuel return line (2) and
through the opening (arrow) – Install the carburetor support,
b 13.8

– Install the carburetor, b 13.5

1 2
– Install actuating lever, b 11

– Reassemble remaining parts in

reverse order
2410RA543 TG

: Push brake cable (1) with short

hook (2) in front through the
hole (arrow) in the crankcase

MS 241 C 151
14. Heating

14.1 Carburetor heating

The heating element is installed

between the switchgear halter and
the carburetor. Power is provided to
the heating element via leads.

The heating element is regulated by

2410RA378 TG

2410RA380 TG
the thermostatic switch on the
underside of the carburetor. 10
0
50
30 20 10
5
10
0
50
30 20 10

20
5
0
20 0 10
5 10 25

The heating element and the : Clip one of the two test leads onto : Clip one test lead to the heating
thermostatic switch must also be a nut of the baffle and the other element, the second test lead to
checked if running problems occur onto a cylinder fin the blade receptacle
when the cold engine is idling or
running at part load, particularly at
If the system is OK, the ohmmeter If the heating element is OK, the
sub-zero temperatures.
will show a reading of approx. 10 Ω ohmmeter will show a reading
Idling problems with a hot engine
in the measuring range "Ω". of approx. 12 Ω in the measuring
range "Ω".
may also indicate a fault in the
If the reading obtained is outside
heating element of the thermostatic
this tolerance, each component
switch.
must be tested separately. Installation

14.1.1 Check overall system

14.1.2 Check heating element
3
In the function check of the overall
– Remove filter base, b 13.1
system, the generator and heating
elements are checked. Precondition 2
is an ambient temperature of at – Pull of switchgear and set it
least + 20 °C (68 °F). aside, pull out the carburetor 1
somewhat in the direction of the

2410RA381 TG
If the temperature is below + 13 °C handle, b 13.5
(55 °F), the thermostatic switch may
be closed and produce false
readings. : Slide the heating element (1)
over the studs so that the hole
– Check the carburetor heating in 1 engages the pin (2)
accordance with the
troubleshooting chart carburetor : Orient the crimped side of the
heating, b 14.2 blade receptacle (3) so that it
2 faces the carburetor
– Remove the air filter, b 13.1
2410RA379 TG

: Push the blade receptacle (3)

– Set ohmmeter to measuring completely onto the connector
range "Ω" tab (arrow)
: Remove blade receptacle (1)
– Reassemble remaining parts in
: Remove heating element (2) reverse order
from the studs

152 MS 241 C
14.1.3 Thermostatic switch Installation
1 2 3
The thermostatic switch is an 3
electronic component that cannot
be tested directly. The functionality
of the thermostatic switch can be
determined using the 2 1
troubleshooting chart, b 14.2

2410RA374 TG
– Remove the carburetor, b 13.5

2410RA364 TG
: Press lead (1) into the
guides (arrows) so that is is
1 – Check that the pump diaphragm behind the peg (2)
and gasket are correctly seated
: Slide on the insulating tube (3)
3 : Hold end cover (1) so that the
2
pump membrane and gasket – Install the carburetor, b 13.5
remain secured
2410RA362 TG

– Press the plug connection

: Position the thermostatic together completely, b 1
switch (2) so that it rests against
the raised part (arrow)
– Reassemble remaining parts in
: Remove screw (1) reverse order
: Screw in the screw (3) and
: Remove thermostatic switch (2) tighten it
– Check correct functioning

: Hold end cover (3) so that the

pump membrane and gasket
remain secured

MS 241 C 153
14.2 Troubleshooting, carburetor heating

Heating element resistance

Measure when
temperature = +20 °C (68 °F)

Resistance no Replace heating

approx. 12 Ω? element, b 14.1.2

yes

Replace thermostatic
switch, b 14.1.3

Carburetor heating element

OK?

Circuit diagram
G = Generator
1 = Rear handle
2 = Front handle
3 = Heating switch
1 4 4 = Thermostatic switch
5 = Heating element (carburetor
heating)

2 5

G
3
0001RA505 TG

154 MS 241 C
14.3 Handle heating systems If the pointer does not move, there
is a break in the circuit.
14.3.1 Troubleshooting
If the ohmmeter shows a very low
The entire handle heating system is value, there is a short circuit in one
maintenance-free and not subject to 1 of the components.
electrical wear. Faults in the
generator, heating elements and In both cases, each component

2410RA382 TG
leads are generally caused by must be checked individually,
mechanical damage. In the process, the generator
connector remains disconnected
Failures in the heating system may from the thermostatic switch
be due to two reasons: : Set heating switch (1) to position connector.
"F"
1. Interruption in the – Test according to the
electrical circuit due to – Set ohmmeter to "Ω" position troubleshooting chart, handle
damage to leads or heating and generator, b 14.7.1
components.

2. Short circuit in electrical circuit – Measure resistance in front

due to insulation damage. handle, b 14.6

– Remove handle molding, b 11.2 – Measure resistance in rear

handle, b 14.5

– Press the plug connection

together completely, b 1
2410RA403 TG
30 20 10
50 5
10
0

25
10 20 0 – After testing, reconnect the leads
and slide the protective tube back
– Move the Master Control lever to over the plug connection.
position "0"
– Reassemble remaining parts in
2410RA401 TG

1 : Clip test leads onto the lead from reverse order

the wiring harness and the lead
from the heating element
: Pull one of the plug connections
out of the guide and slide Carburetor heating
insulating tube (1) towards wiring
harness – Disconnect plug connection to
thermostatic switch, then reinstall
carburetor, filter base and baffle,
b 13.5

All electrical components of the

handle heating system are
connected in series with the
ohmmeter.

If the system is OK, the ohmmeter

2410RA402 TG

1 will show a reading of approx. 10 Ω

in the measuring range "Ω".

: Disconnect plug connection (1)

MS 241 C 155
14.4 Heating switch Installation

2
– Remove filter base, b 13.3
4 3
2
3 1
1

2410RA386 TG
1

2410RA501 TG
: Remove screw (1)
2410RA383 TG

: Remove socket terminal (2) at : Push blade receptacle (1) onto

the holder (4) and remove the straight connector tag of the
2 socket terminal (2) so that the
ground wire (3) from the
guide (arrow) crimped side faces the angled
: Remove blade receptacle (1) connector tag (3)
: Check holder (4), if necessary,
: Remove contact sleeve (2)
remove from the air guide shroud
and replace

2 1
1
2

2410RA502 TG
1
2410RA384 TG

2410RA500 TG

: Press holder (1) as far as it will go

into the guides (arrows) of the air
: Unscrew nut (1) guide shroud
: Disconnect the ground wire (1)
: Remove washer (2) from the socket terminal (2)

– Check the individual parts and

replace if necessary
1
2410RA385 TG

: Pull heating switch (1) off to the

inside and examine, replace if
necessary

156 MS 241 C
 1 2
1

2410RA387 TG

2410RA389 TG

2410RA392 TG
2 1 2

: Orient socket terminal of the : Fit washer (1) : Push the contact sleeve (1) into
ground wire so that the connector the heating switch (2) as far as it
tab (1) points toward the : Tightly screw on nuts (2) will go
carburetor and the flat
faces (arrows) engage between
the fins (2) of the holder
1
– Position socket terminal at the
holder
1

2410RA393 TG
2410RA390 TG
2

: Position ground wire (1) so that : Press lead (1) into the
the crimped side (arrow) of the guides (arrows)
cable lug faces upward
2410RA388 TG

1 : Screw in the screw (2) and

tighten it
1
: To ensure correct switch position,
orient the heating switch (1) so
– Checking correct functioning
that the groove faces the
pin (arrow)

: Push the heating switch (1)

through the contact ring of the 2410RA394 TG

ground wire into the hole of the

1
holder (2)
: Push on blade receptacle (1) so
that the crimped side faces the
carburetor
2410RA391 TG

– Reassemble remaining parts in

reverse order
: Press ground wire (1) as far as it
will go into the guide (arrow)

MS 241 C 157
14.5 Heating element in If the heating element is intact, the
handle ohmmeter will indicate a value
of approx. 1.6 Ω 1 1
(reading 1.5...2.0 Ω) in the
– Remove the handle molding and
measuring range "Ω".
trigger interlock, b 11.2
The heating element must be
replaced if the value is outside this

2410RA396 TG
range.

Is the heating element inoperable

despite a successful resistance
measurement? The connecting leads must be
2 routed so that the thin lead runs
1 – Test generator and heating underneath the thick lead.
switch, b 14.3, b 14.7
2410RA395 TG

The heating element leads must not

cross one another.
– Remove and examine
connecting leads, replace if
: Push connectors and socket
: Pull insulating tubes (1) and (2) necessary, b 14.9
terminals together
with plug connections out of the
guides
: Slide insulating tubes (1) over the
Installation
plug connections

1 1

1
1 2
5902RA595 TG
2410RA396 TG

2410RA398 TG
: Slide insulating tubes (1) towards : Position new heating element (1)
connecting leads and disconnect so that it rests against the
edge (arrow) of the handle – : Press insulating tubes (1) and (2)
plug connections
make certain that the heating with plug connections into the
element is inserted completely guides (arrows)

An incompletely inserted heating

1 element cannot transfer the heat
completely to the handle – danger
of overheating of the heating
element.

– Press the plug connections

2410RA405 TG

together completely, b 1
30 20 10
50 5
0
10 0
20
5 10

: Check heating element (1) and

replace if necessary

158 MS 241 C
 If the reading obtained is outside
this tolerance, then the front
handle (front handle heating
1 element) must be replaced,
b 10.4.1.

Is the heating element inoperable

despite a successful resistance

2410RA399 TG

2410RA400 TG
measurement?
30 20 10
50 5
0
10
5 10
20 0
– Remove and examine
connecting lead to front handle
The black lead of the handle heating : Clip one test lead to the terminal heating element, replace if
must be routed underneath the gray socket (1) of the thick connecting necessary, b 14.9
lead of the wiring harness. lead and the second to the
contact sleeve of the heating
– Examine wiring harness, replace
: Press the leads of the handle switch
if necessary, b 14.3, b 14.8
heating and the wiring harness
into the guide (arrows) If the heating element is intact, the
– Test generator and heating
ohmmeter will indicate a value
switch, replace if necessary,
– Reassemble remaining parts in of approx. 6.4 Ω
b 14.7, b 14.4
reverse order (reading 6.0...8.0 Ω) in the
measuring range "Ω".
– Reassemble parts in reverse
If the reading obtained is outside order
14.6 Heating element in front
handle this tolerance, then the front
handle (front handle heating
element) must be checked directly
The heating element in the front at the connecting leads.
handle cannot be replaced. In case
of damage, the complete front – Disconnect plug connections at
handle must be replaced. the front handle, b 10.4.1
Check heating element

– Remove the handle molding,

b 11.2

The functioning of the heating 1

element in the front handle can be 2
checked simply using the following
test procedure.
2410RA404 TG

– Disconnect the plug connections

of the heating element at the 00
50
30 20 10
5

handle
: Clip test leads to the
Carry out measurement between connectors of the leads (1)
the two socket terminals and the and (2)
contact sleeve.
If the heating element is intact, the
– Set heating switch to F ohmmeter will indicate a value
of approx. 6.4 Ω
(reading 6.0...8.0 Ω) in the
measuring range "Ω".

MS 241 C 159
14.7 Generator Installation

– Press the plug connection

– Remove the control unit, b 7.3
together completely, b 1
– Remove the flywheel, b 7.6

– Remove the pre-separator, 1

0001RA448 TG
b 7.2

– Remove the carburetor, b 13.5

: Check generator and
– Remove carburetor support, poles (arrow) for cracks or other
b 13.8 damage. Replace generator if

2410RA408 TG
necessary.
– Remove the air guide shroud,
b 13.4.2
: Fit generator (1) with connecting
lead (arrow) facing the housing

1 2 – Check that the generator is

seated correctly

– Insert and tighten down the

screws
0001RA449 TG
2410RA406 TG

: Check magnet ring (arrow) in

flywheel for cracks or other
: Remove grommet (1) and damage. Replace flywheel if
generator lead (2) from the necessary. 1
guide (arrow)

2410RA409 TG
2 3

1 : Push terminal socket (1) of the

generator lead through the
opening (arrow)
2410RA407 TG

: Remove screws (1)

: Remove generator (2) and pull

the lead (3) out of the
guides (arrows)

: Pull lead (3) out of the opening of

the crankcase

160 MS 241 C
 1 1

2410RA410 TG

2410RA413 TG

2410RA415 TG
1

: Lay generator lead (1) in bottom : Press generator lead (1) on the The lead (1) must be seated
of recess (arrow) inside of the crankcase into the completely in the recess (arrow).
guide (arrow) so that it lies snug
The flywheel must not touch the
generator lead
1 – power supply can be interrupted.
1 2
– Reassemble remaining parts in
reverse order
2410RA411 TG

2410RA414 TG

: Press generator lead (1) into the

guides (arrows) so that it runs : Push grommet (1) onto the
snug against the crankcase generator lead (2) so that the
cone (arrow) faces the generator

– Install air guide shroud, b 13.4.2

1
2410RA412 TG

: Pull the generator lead (1)

through the opening (arrow) until
it lies snug against the crankcase

MS 241 C 161
14.7.1 Troubleshooting chart, handle heating systems and generator

Start

yes Do both handles become

warm?

no
Activate
no
Heating switch switch
set to „F“?
yes

Measure resistance of the individual

heating elements using
ohmmeter

Disconnect plug connection to

thermostatic switch
b 13.5

Check rear handle heating element:

in good condition?
Is it completely against the no
handle housing?
Replace
yes handle heating
element,
Resistance of no b 14.5
handle heating element
approx. 1.6 Ω?
yes

Check generator
Resistance between engine ground no Replace
and generator connection generator,
approx. 0.5–1 Ω? b 14.7

yes

1 2 3

162 MS 241 C
 1 2 3

Disconnect and clear plug connections to

front handle heating element,
b 10.4.1

check handle heating Replace

no
element front handle,
resistance approx. 6.4 Ω? b 10.4.1

yes

Test heating switch Replace

(contact sleeve against switch housing) no heating switch,
Closed: approx. 0 Ω ? b 14.4
Open: no continuity,
b 14.3

yes

Reassemble plug connection

to thermostatic switch,
b 13.5

System OK

MS 241 C 163
14.7.2 Summary of test connections and test values

– The wires in the handle must be

unplugged to test the individual
components separately

Component Ohmmeter Resistance Ω If faulty

connection (either test
lead can be used)
Lead 1 Lead 2 Re- Actual Cause Remedy
quired
Switch Switch Switch < 0.5 - Switch faulty Replace switch
connection housing
1)

Heating element in Connector Connector 1.6 1.5 - 2.0 Heating element

handle to lead to lead OK
from from
heating heating
element element

- Break in wire, Replace heating

heating element element and/or
damaged repair insulation

0 Short circuit due to

damaged insulation

Heating element in Connector Connector 6.4 6.0...8.0 Heating element

front handle to lead to lead OK
from front from front
handle handle
heating heating
element element

- Break in wire, Replace front

heating element handle
damaged

0 Short circuit due to repair insulation

damaged insulation

1)
Pull wire out for this purpose

164 MS 241 C
Component Ohmmeter Resistance Ω If faulty
connection (either test
lead can be used)
Lead 1 Lead 2 Re- Actual Cause Remedy
quired
Generator Connector Weight 0.6 0.5 - 1 Generator OK
to
generator
lead

- Break in wire, Replace generator

generator damaged
0 Short circuit due to Repair insulation
damaged insulation

Circuit diagram G = Generator

1 = Rear handle
2 = Front handle
3 = Heating switch
1 4 4 = Thermostatic switch
5 = Heating element (carburetor
heating)
2 5

G
3
0001RA505 TG

MS 241 C 165
14.8 Wiring harness : Disconnect plug connections and
remove wiring harness (3)
If the wiring harness if faulty, it must
be replaced.
Installation
– Remove shroud, b 6.4
– Press the plug connections
together completely, b 1

2410RA421 TG
– Remove the handle molding and
trigger interlock, b 11.2

– Remove the carburetor, b 13.5 3 The wires of the handle must be

4 seated completely in the
– Remove carburetor support,
guide (arrow).
b 13.8 5
– Remove the air guide shroud, 1
b 13.4.2

2410RA419 TG
– Lower the tank housing and 1 2
remove the cover of the plug 5
connections, b 10.4.1
: Push insulating tubes (1) onto 4
the wires with the socket
terminal (2) and (3)

2410RA422 TG
1 2 1 3
Grommet (4) must rest against the
protective tube (5).
: Press the plug (1) of the thin
connecting wire (2) into the
terminal socket (3) of the wiring
2 1 harness (4) as far as it will go
2410RA417 TG

: Slide on the insulating tube (5)

2 3
: Pull plug connections (1) and (2)
with insulating tubes out of the 1
2410RA420 TG

guides (arrows)

: Press plug (1) of handle into the

3 terminal socket (2) of thick wire
as far as it will go
2410RA423 TG

1
: Slide on the insulating tube (3)

: Position insulating tube (1) with

2410RA418 TG

plug connection at the edge of

the tank housing and push it into
2 the guide (arrow) as far as it will
go
: Push insulating tube (1) and (2)
toward the wiring harness

166 MS 241 C
 14.9 Connecting leads heating
1 elements 1 4 2

In the absence of a fault in the wiring

harness, heating elements,
generator or heating switch, then
the problem may also be due to
damaged connecting leads

2410RA424 TG

2410RA429 TG
between the front and rear handle
heating elements. 1 3

: Run the thin wire (1) with a – Remove shroud, b 6.4 : Push insulating tubes (1) toward
loop (arrow) around the fin and connecting leads and disconnect
press it into the guide as far as it – Remove handle molding, trigger plug connections (2) and (3)
will go interlock and throttle trigger,
b 11.2 Do not disconnect plug
connection (4) with insulating tube.
– Lower the tank housing and
1 remove the cover of the plug
connections, b 10.4.1

2
2410RA425 TG

2410RA431 TG
2
: Position insulating tube (1) with 1
plug connection at the edge of
2410RA430 TG

the tank housing and push it into : Pull plug connections (1) and (2)
the guide (arrow) as far as it will with insulating tubes out of the
go guides (arrows)
: Pull connecting lines (1) and (2)
– Install cover over the plug out of the guide (arrows)
connections, lift and fasten tank
housing, b 10.4.1

– Install air guide shroud, b 13.4.2

– Reassemble remaining parts in

reverse order
3
1
2410RA428 TG

: Pull plug connections (1), (2)

and (3) with insulating tubes out
of the guides

MS 241 C 167
 2 1
1 1 4

2410RA432 TG
4

2410RA434 TG

2410RA436 TG
3

: Slide insulating tubes (1) towards : Connect the thin connecting : Position insulating tube (1) with
connecting leads and disconnect lead (1) with the thin lead (2) of plug connection at the edge of
plug connections the wiring harness and the lower the tank housing and push it into
lead (3) of the handle heating the guide (arrow) as far as it will
– Remove and examine element go
connecting leads, replace if
necessary – Push connectors and socket
terminals together as far as
possible 1
Installation
: Slide insulating tubes (4) over the
– Press the plug connection plug connections
together completely, b 1

Run all leads under the throttle rod.

2410RA437 TG
4 2

2 1 : Position insulating tube (1) with

1 plug connection at the edge of
4 the tank housing and push it into
the guide (arrow) as far as it will
2410RA435 TG

go
3
2410RA433 TG

: Connect the thick connecting

3 1 lead (1) with the long lead (2) of
1
the handlebar and the upper
: Push insulating tubes (1) onto lead (3) of the handle heating
both ends of the connecting element
leads (2) and (3)
– Push connectors and socket
terminals together as far as
2410RA438 TG

possible

: Slide insulating tubes (4) over the

plug connections : Run the thin wire (1) with a
loop (arrow) around the fin and
At the handlebar, the long lead must press it into the guide as far as it
be run under the shorter lead. will go

168 MS 241 C
 1 1

2410RA439 TG

2410RA441 TG
2
3

: Position insulating tube (1) with The thin connecting lead must be
plug connection at the edge of run underneath the thick connecting
the tank housing and push it into lead.
the guide (arrow) as far as it will
go : Starting at the cover (1) of the
plug connections, route the leads
and press them into the
guide (arrow)

3 : Press plug connection (2) of the

2 thin connecting lead into the right
guide and plug connection (3) of
2 the thick connecting lead into the
left guide of the handle
2410RA440 TG

– Reassemble remaining parts in

1 reverse order

: Orient cover (1) so that the

pegs (2) engage the holes and
the tab (3) engages the
fin (arrows)

– Replace cover, insert and tighten

screw
– Ensure that wires are not
pinched

MS 241 C 169
15. Special tools

New special tools

No. Designation Part No. Use Re-

marks

1 Press sleeve 1143 893 2400 Pressing in oil seal

(Ignition side)
2 Wiring tool 5910 890 4000 Inserting wires in the guides

Existing special tools

No. Designation Part No. Use Re-

marks

1 Carburetor and crankcase tester 0000 850 1300 Testing crankshaft in engine and
carburetor for leakage
- Connector 0000 855 9200 Testing carburetor for leaks
- Hose for leakage test 1110 141 8600 Testing carburetor for leaks
- Plug for leakage testing 1122 025 2200 Testing decompression valve for leaks
2 Sealing plate 0000 855 8106 Testing crankshaft in engine and
carburetor for leakage
3 Installing tool 0000 890 2201 Installation of starter rope guide
bushing
4 Clamping strap 0000 893 2600 Tension the piston rings
5 Locking strip 0000 893 5904 Blocking crankshaft
6 Bit T 27 x 125 0812 542 2104 Removing and installing spline socket
head screws with electric or pneumatic
screwdrivers; tightening down screws
with torque wrench
7 Wooden assembly block 1108 893 4800 Positioning piston/lowering tank
housing maintaining spacing
8 Assembly drift 1110 893 4700 Removing and installing piston pins
9 Setting gauge 1111 890 6400 Setting air gap between control unit
and flywheel
10 Installing tool 1116 893 4800 Installing rewind spring
11 Assembly tube 1117 890 0900 Hook in clutch spring
12 Flange 1118 850 4200 Leakage test
13 Press sleeve 1118 893 2401 Pressing in oil seal
(Clutch side)
14 Combination wrench 1129 890 3401 Spark plug 1)
15 Installing sleeve 1141 893 4600 Protection of the oil seal
(Ignition side/clutch side)

170 MS 241 C
 No. Designation Part No. Use Re-
marks

16 Service tool ZS 5910 007 2201 Removal and installation of

including crankshaft (clutch side)
Washer 5910 893 2103
– Washer 5910 893 2103 Pulling together the crankcase
in supplementation to service tool
kit ZS 5910 007 2200
- Screw sleeve 5910 893 2420 Installing crankshaft
17 Service tool kit AS 5910 007 2205 Removal and installation of
crankshaft (clutch side)
- Screw sleeve 5910 893 2409 Pulling together the crankcase
18 Test lead 5910 840 0903 M-Tronic diagnostic and testing tasks
19 Clamping strip for assembly 5910 850 1650 Clamp machine to assembly stand
stand
20 ZAT 4 ignition tester 5910 850 4503 Test ignition system
21 ZAT 3 ignition tester 5910 850 4520 Test ignition system
22 Flange 5910 855 4201 Sealing the cylinder exhaust port for
leakage test
23 Torque wrench 5910 890 0302 Screw connections (0.5 to 18 Nm)
24 Torque wrench 5910 890 0312 Screw connections (6 to 80 Nm)
25 Installing tool 10 5910 890 2210 Fit hookless snap rings in piston
- Sleeve 5910 893 1707 Sleeve for installing tool 10
26 Bit T 27 x 150 5910 890 2400 IS-P screws
27 Assembly hook 5910 890 2800 Detach springs from clutch shoes
28 Assembly stand 5910 890 3101 Holding chain saw for servicing /
repairs
29 Puller 5910 890 4400 Extracting the oil seal
- Jaws (with profile no. 6) 0000 893 3711 Extracting the oil seal
30 Puller 5910 890 4504 Removing flywheel
31 Stud puller, M8 5910 893 0501 Removing rail mounting studs
32 Assembly hook 5910 893 8800 Remove pick-up body
33 Installing tool 5910 893 9600 Removing and installing collar nuts on
chain sprocket cover

Remarks:
1) Use only for releasing.

MS 241 C 171
16. Service accessories

No. Designation Part No. Use

1 STIHL multi-purpose grease 0781 120 1109

2 Grease (225 g tube) 0781 120 1111 Oil seals, sliding and bearing points

3 STIHL special lubricant 0781 417 1315 Bearing bore in rope rotor, rewind spring in fan
housing

4 STIHL press fluid OH 723 0781 957 9000 Rubber elements antivibration elements

5 Medium-strength thread-locking 0786 111 2101

adhesive (Loctite 242)

6 Standard solvent-based Cleaning mating surfaces and the carburetor,

degreasant not containing any cleaning the crankshaft stub and tapers in
chlorinated or halogenated flywheel
hydrocarbons

172 MS 241 C
englisch / english
0455 741 0123. M0,7. A11. DDS. Printed in Germany