BORUSAN MAKINA & POWER SYSTEMS TRAINING DEPARTMENT

Caterpillar
C6.6 Model
Marine Genset
Training Course

Istanbul - 2012
 General Information

 Fuel System

 Air Inlet And Exhaust System

 Lubrication System

 Cooling System

 Electronic System

 Maintenance

 Diagnostic And Troubleshooting

 Engine Monitoring System

 Generator

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Model View Illustrations :

(1) Rain Cap for Air Filter

(2) Top Oil Filler Cap
(3) Water Pump
(4) Cover for Belts
(5) Oil Gauge (Dipstick)
(6) Single Oil Filter
(7) Solenoid For Air
Starting Motor
(8) Air Starting Motor
(9) Electric Starting
Motor
(10) Drains on Exhaust
Manifold
(11) Terminal Box

(12) AC Connection
(13) Isolator Keyswitch
(14) Drain on Cylinder
Block
(15) Alarm Tank
Switch
(16) Outlet for the
Aftercooler
(17) Water Inlet for
Auxiliary Water Pump
(18) Outlet for Keel
Cooling

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 (12) Engine Cover
(13) Blanket on Exhaust Elbow
(14) Rain Cap for Air Cleaner
(15) MCS Control Panel
(16) Generator Terminal Box
(17) Isolator Keyswitch
(18) 20 AMP Circuit Breaker
(19) 90 AMP Circuit Breaker for
the 24 Volt Cold Start
(20) Electronic Control Module
(ECM)
(21) Differential Switch for the
Primary Fuel Filters
(22) Differential Switch for the
Secondary Fuel Filters

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Engine Identification :
Caterpillar products are identified with serial numbers and with arrangement numbers. In some of
the cases, modification numbers are used. These numbers are shown on the Serial Number plates
and the Engine Information Plates and shown on the Generator Identification plates that are
mounted on the product.

Caterpillar dealers need these numbers in order to determine the components that were included
with the product. This permits accurate identification of replacement part numbers.

(1) Engine Information Plate

(2) Serial Number Plate
(3) Generator Identification Plate

The engine information plate is located on the left side of the cylinder block to the rear of the front
engine mounting.

The serial number plate is located on the front of the frame.

The generator identification plate is located on the front side of the terminal box.

Emissions Certification Film :

The IMO label is mounted on the engine.

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Reference Information :

Information for the following items may be needed to order parts for your marine engine. Locate
the information for your engine. Record the information on the appropriate space. Make a copy of
this list for a record. Keep this information for future reference.

Reference Information

Engine Model

Engine Serial Number

Engine Arrangement Number

Modification Number

Engine Low Idle Rpm

Engine Full Load Rpm

Performance Specification Number

Primary Fuel Filter Number

Water Separator Element Number

Secondary Fuel Filter Element Number

Lubrication Oil Filter Element Number

Auxiliary Oil Filter Element Number

Supplemental Coolant Additive Maintenance Element Number (Optional)

Total Lubrication System Capacity

Total Cooling System Capacity

Air Cleaner Element Number

Alternator Belt Number

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Engine Specifications :
(A) Exhaust valve
(B) Inlet valve

Inlet (Long)

Exhaust (Short)

Note: The front of the engine is opposite the flywheel end. The left side and the right side of the
engine are viewed from the flywheel end. The No. 1 cylinder is the front cylinder.

Engine Specifications
Cylinders and Arrangement In-Line 6 Cylinders
Valves per cylinder 4
Bore 105 mm
Stroke 127 mm
Compression Ratio 16.2:1
Aspiration Turbocharged & Aftercooled
Combustion Direct Injection
Displacement 6.6 Lt.
Firing Order (Standard Rotation – CCW) 1, 5, 3, 6, 2, 4
Rotation (viewed from flywheel)
Engine Power 208 bhp
Engine Speed 1500 rpm
Rating Prime

The six cylinders are arranged in-line. The cylinder head assembly has two inlet valves and two
exhaust valves for each cylinder. The ports for the exhaust valves are on the right side of the
cylinder head. The ports for the inlet valves are on the left side of the cylinder head. Each cylinder
valve has a single valve spring.

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Main Engine Parts :
Cylinder Block :

The cast iron cylinder block for the C6.6 engine has six cylinders which are arranged in-line. The
cylinder block is made of cast iron. The cylinder block provides support for the full length of the
cylinder bores. The cylinder bores are machined into the block. Worn cylinders may be rebored in
order to accommodate oversize pistons and rings.

The cylinders are honed to a specially controlled

finish in order to ensure long life and low oil
consumption.

The cylinder block has seven main bearings which

support the crankshaft. The main bearings are
available in three sizes in order to allow the
crankshaft to be reground twice. Thrust washers
are installed on both sides of number six main
bearing in order to control the end play of the
crankshaft. The thrust washers can only be
installed one way.

Passages supply the lubrication for the crankshaft bearings. These passages are machined into
the cylinder block.

Cooling passages are cast into the cylinder block in order to allow the circulation of coolant.
The cylinder block has a bush that is installed for the front camshaft journal. The other camshaft
journals run directly in the cylinder block.

The engine has a cooling jet that is installed in the cylinder block for each cylinder. The piston
cooling jet sprays lubricating oil onto the inner surface of the piston in order to cool the piston.
A multi-layered steel (MLS) cylinder head gasket is used between the engine block and the
cylinder head in order to seal combustion gases, water, and oil.

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Cylinder Head :

The engine has a cast iron cylinder

head. The lower part of the inlet
manifold is integral within the cylinder
head. There are two inlet valves and
two exhaust valve for each cylinder.
Each pair of valves are connected by a
valve bridge that is controlled by a
pushrod valve system. The ports for the
inlet valves are on the left side of the
cylinder head. The ports for the exhaust
valves are on the right side of the
cylinder head. The valve stems move in
valve guides that are machined into the
cylinder head. There is a renewable oil
seal that fits over the top of the valve
guide. The valve seats are replaceable.

Pistons, Rings and Connecting Rods :

The pistons have a Quiescent

combustion chamber in the top of the
piston in order to provide an efficient mix
of fuel and air. The piston pin is off-
center in order to reduce the noise level.

The pistons have two compression rings

and an oil control ring. The groove for
the top ring has a hard metal insert in
order to reduce wear of the groove. The
piston skirt has a coating of graphite in
order to reduce the risk of seizure when
the engine is new.

The correct piston height is important in

order to ensure that the piston does not
contact the cylinder head. The correct
piston height also ensures the efficient
combustion of fuel which is necessary in
order to conform to requirements for
emissions.

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A piston and a connecting rod are matched to each cylinder. The piston height is controlled by the
distance between the center of the big end bearing and the center of the small end bearing of the
connecting rod. Three different lengths of connecting rods are available in order to attain the
correct piston height. The three different lengths of connecting rods are made by machining the
blank small end bearing of each rod at three fixed distances vertically above the centerline of the
big end bearing.

The connecting rods are machined from forged molybdenum steel. The connecting rods have
bearing caps that are fracture split. The bearing caps on fracture split connecting rods are retained
with Torx screws. Connecting rods with bearing caps that are fracture split have the following
characteristics:

 The splitting produces an accurately matched surface on each side of the fracture for
improved strength.

Crankshaft :

The crankshaft is a chromium molybdenum steel

forging. The crankshaft has seven main journals.
Thrust washers are installed on both sides of number
six main bearing in order to control the end play of
the crankshaft.

The crankshaft changes the linear energy of the

pistons and connecting rods into rotary torque in
order to power external equipment.

A gear at the front of the crankshaft drives the timing

gears. The crankshaft gear turns the idler gear which
then turns the following gears:

 Camshaft gear
 Fuel injection pump and fuel transfer pump
 The idler gear is driven by the crankshaft gear
which turns the gear of the lubricating oil.

Lip type seals are used on both the front of

the crankshaft and the rear of the crankshaft.

A timing ring is installed to the crankshaft.

The timing ring is used by the ECM in order
to measure the engine speed and the engine
position.

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Vibration Damper :

The force from combustion in the cylinders will cause the

crankshaft to twist. This is called torsional vibration. If the
vibration is too great, the crankshaft will be damaged.
The vibration damper is filled with viscous fluid in order to
limit the torsional vibration.

Gears and Timing Gear Case :

The crankshaft oil seal is mounted in the aluminum timing

case. The timing case cover is made from pressed steel.

The timing gears are made of steel.

The timing case is made of aluminum. The timing gears

are stamped with timing marks in order to ensure the
correct assembly of the gears. When the number 1 piston
is at the top center position of the compression stroke, the
marked teeth on the idler gear will align with the marks
that are on the fuel injection pump gear, the camshaft
gear, and the gear on the crankshaft. There are no timing
marks on the rear face of the timing case.

The crankshaft gear drives an upper idler gear and a lower idler
gear. The upper idler gear drives the camshaft and the fuel
injection pump. The lower idler gear drives the oil pump. The water
pump drive gear is driven by the fuel injection pump gear.

The camshaft and the fuel injection pump rotate at half the engine
speed.

(1) Fuel injection pump drive gear (4) Crankshaft gear

(2) Camshaft gear (5) Oil pump idler gear
(3) Idler gear (6) Oil pump gear

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Camshaft :

The engine has a single camshaft. The camshaft is made

of cast iron. The camshaft lobes are chill hardened.

The camshaft is driven at the front end. As the camshaft

turns, the camshaft lobes move the valve system
components. The valve system components move the
cylinder valves.

The camshaft gear must be timed to the crankshaft gear.

The relationship between the lobes and the camshaft gear
causes the valves in each cylinder to open at the correct
time. The relationship between the lobes and the camshaft
gear also causes the valves in each cylinder to close at
the correct time.

1. Long rocker arm 5. Electronic fuel injector

2. Intake valve bridge 3 6. Large rubber boot
3. Short exhaust rocker arms 7. Injector harnesses
4. Exhaust valve bridge

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Fuel System :

Cleanliness of the Engine :

The entire engine should be washed with a high pressure water system in order to remove dirt and
loose debris before starting a repair on the fuel system. Ensure that no high pressure water is
directed at the seals for the injectors

Note : It is important to maintain extreme cleanliness when working on the fuel system, since even
tiny particles can cause engine or fuel system problems.

Environment :

When possible, the service area should be

positively pressurized in order to ensure that the
components are not exposed to contamination
from airborne dirt and debris. When a component
is removed from the system, the exposed fuel
connections must be closed off immediately with
suitable sealing plugs. The sealing plugs should
only be removed when the component is
reconnected. The sealing plugs must not be
reused. Dispose of the sealing plugs immediately
after use. Contact your nearest Caterpillar Dealer
in order to obtain the correct sealing plugs.

New Components :

High pressure lines are not reusable. New high pressure lines are manufactured for installation in
one position only. When a high pressure line is replaced, do not bend or distort the new line.
Internal damage to the pipe may cause metallic particles to be introduced to the fuel.

All new fuel filters, high pressure lines, tube assemblies and components are supplied with sealing
plugs. These sealing plugs should only be removed in order to install the new part. If the new
component is not supplied with sealing plugs then the component should not be used.
The technician must wear suitable rubber gloves. The rubber gloves should be disposed of
immediately after completion of the repair in order to prevent contamination of the system.

Refueling :

In order to refuel the diesel fuel tank, the refueling pump and the fuel tank cap assembly must be
clean and free from dirt and debris. Refueling should take place only when the ambient conditions
are free from dust, wind and rain. Only use fuel that free from contamination.

Fuel :

Diesel fuels that meet the Caterpillar Specification for Distillate Diesel Fuel are recommended.
These fuels will help to provide maximum engine service life and performance. In North America,
diesel fuel that is identified as No. 1-D or No. 2-D in "ASTM D975" generally meet the
specifications. Diesel fuels from other sources could exhibit detrimental properties that are not
defined or controlled by this specification.

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Note : Operating with fuels that do not meet Caterpillar's recommendations can cause the
following effects: starting difficulty, poor combustion, deposits in the fuel injectors, reduced service
life of the fuel system, deposits in the combustion chamber and reduced service life of the engine.

Summary :

Contamination control is critical with the common

rail fuel system. Very high pressures require
close tolerances in the fuel injection pump and
injectors. It is important that technicians pay
close attention to cleanliness and contamination
control during even the most routine
maintenance.

Contamination can cause injector failure, high

leakoff rates, and pump failure. Keep
workbenches uncluttered and free of debris.
Sweep the floors daily and clean up spills
immediately. Avoid performing engine
maintenance outdoors, especially in windy or
dusty conditions.

Keep components in their original packaging until ready to install, and inspect packaging to ensure
components are still sealed and free of dirt or damage. During routine filter changes, have the
replacement filters ready to install to minimize exposure to contaminants. Do not pre-fill fuel filters.
If fuel filters are pre-filled, fuel system failure will occur.

High pressure fuel lines are single use items and must be replaced after unseating any bolt. The
common rail fittings/ports and the injector fittings/ports must be capped immediately after
unseating. Do not remove the caps from new components until just before the fittings are
tightened.

Fuel purity is critical to engine performance and fuel system integrity. Only use fuel that has been
properly stored or transported in clean containers. Only use good quality fuel that is clean and free
of water.

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(1) Electronic unit injector (7) Fuel pressure sensor
(2) Solenoid for the fuel injection pump (8) Engine oil pressure sensor
(3) Secondary speed/timing sensor (9) Inlet air temperature sensor
(4) Fuel injection pump (10) Coolant temperature sensor
(5) Primary speed/timing sensor (11) Diagnostic connector
(6) Boost pressure sensor (12) Electronic control module (ECM)

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Low Pressure Fuel System :

(1) Primary fuel filter

(2) Water separator

(3) Fuel transfer pump

(4) Secondary fuel filter

(5) Fuel Injection Pump

(A) Outlet for high

pressure fuel to the high
pressure fuel manifold

(B) Return from the

Pressure Relief Valve
(PRV) on the high
pressure fuel manifold

(C) Return to fuel tank

(D) Return from the

Electronic Unit Injectors

(E) Fuel in from the fuel

tank

Fuel is drawn from the fuel tank (E) through a

10 micron primary fuel filter (1) and the water
separator (2) to the transfer pump (3). The
transfer pump increases the fuel pressure to
400 kPa to 500 kPa. The fuel passes to a 2
micron fuel filter (4). The fuel filter removes
particulates from 10 microns to 2 microns in
size in order to prevent contamination of the
high pressure components in the fuel system.
Fuel passes from the fuel filter to the fuel
injection pump (5). The fuel is pumped at an
increased pressure to the Fuel manifold (rail).

Excess fuel from the fuel manifold (rail) returns to the tank through a non-return valve. There is a
small orifice in the fuel filter base in order to bleed any air back to the tank.

The leak off fuel from the electronic unit injectors returns from a connection in the cylinder head to
the pressure side of the transfer pump

Note : An optional fuel cooler is available on C6.6 marine generator sets. The fuel cooler cools the
fuel returning to the fuel tank.

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High Pressure Fuel System :

Safety :

Warning : Contact with high pressure fuel may cause fluid penetration and burn hazards. High
pressure fuel spray may cause a fire hazard. Failure to follow these inspection, maintenance and
service instructions may cause personal injury or death.

The high pressure fuel lines are the fuel lines that are between the high pressure fuel pump and
the high pressure fuel manifold and the fuel lines that are between the fuel manifold and cylinder
head. These fuel lines are different from fuel lines on other fuel systems. Fuel pressures between
the fuel injection pump and the fuel injectors can reach 160 MPa (1600 bar), so specific safety
procedures must be carefully followed.

This is because of the following items:

 The high pressure fuel lines are constantly charged with high pressure.
 The internal pressures of the high pressure fuel lines are higher than other types of fuel
system.
 The high pressure fuel lines are formed to shape and then strengthened by a special
process.

Do not step on the high pressure fuel lines. Do not deflect the
high pressure fuel lines. Do not bend or strike the high
pressure fuel lines. Deformation or damage of the high
pressure fuel lines may cause a point of weakness and
potential failure.

Do not check the high pressure fuel lines with the engine or
the starting motor in operation. After the engine has stopped
allow 60 seconds to pass in order to allow the pressure to be
purged before any service or repair is performed on the
engine fuel lines.

Do not loosen the high pressure fuel lines in order to remove air from the fuel system. This
procedure is not required.

The common rail fuel system is a self-bleeding fuel system that doesn’t require air to be purged
from the system. Fuel lines should be left untouched and fittings should remain torqued at the
specified settings. Once a fitting has been loosened, the entire fuel line must be replaced with a
new part to ensure proper seating and safe, leak-free performance.

Do not use compressed air or solvent to clean any fuel system components. Do not remove
components from the packaging until ready to install.

Visually inspect the high pressure fuel lines before the engine is started. This inspection should be
each day.

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The rubber boots that seal the valve cover opening are also single use parts.

Any retaining clips that are removed should be replaced with new clips to ensure they fasten
properly. During reassembly, be sure the clips are placed in the proper locations to prevent
vibration and potential leaks from occurring.

If you inspect the engine in operation, always use the proper inspection procedure in order to avoid
a fluid penetration hazard.

 Inspect the high pressure fuel lines for damage, deformation, a nick, a cut, a crease, or a dent.
 Do not operate the engine with a fuel leak. If there is a leak do not tighten the connection in
order to stop the leak. The connection must only be tightened to the recommended torque.
 If the high pressure fuel lines are torqued correctly and the high pressure fuel lines are leaking
the high pressure fuel lines must be replaced.
 Ensure that all clips on the high pressure fuel lines are in place. Do not operate the engine with
clips that are damaged, missing or loose.
 Do not attach any other item to the high pressure fuel lines.
 Loosened high pressure fuel lines must be replaced. Also removed high pressure fuel lines
must be replaced.

(1) High pressure fuel line (5) Fuel transfer pump

(2) Fuel manifold (rail) (6) Solenoid for the fuel injection pump
(3) Fuel pressure sensor (7) Fuel injection pump
(4) Fuel pressure relief valve

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The fuel injection pump (7) feeds fuel to the high pressure fuel manifold (2). The fuel is at a
pressure of 70 MPa (700 bar) to 130 MPa (1300 bar). A pressure sensor (3) in the high pressure
fuel manifold (2) monitors the fuel pressure in the high pressure fuel manifold (2). The ECM
controls a solenoid (6) in the fuel injection pump (7) in order to maintain the actual pressure in the
high pressure fuel manifold (2) at the desired level. The high pressure fuel is continuously available
at each injector. The ECM determines the correct time for activation of the correct electronic unit
injector which allows fuel to be injected into the cylinder. The leakoff fuel from each injector passes
into a drilling which runs along the inside of the cylinder head. A pipe is connected to the rear of
the cylinder head in order to return the leakoff fuel to the pressure side of the fuel transfer pump.

Duplex primary fuel filters allow the fuel filters

to be changed while the engine is running. In
the duplex filter system, the primary fuel filter
assembly consists of the fuel filter base (6), the
primary fuel filter elements (7), the fuel/water
separators (8), and the drain valves (9). The
fuel priming pump (10) is located next to the
fuel filters in the duplex filter system.

The duplex filter system primary fuel filter base

includes a control lever (11) that directs fuel
flow through one or both filters. In the left
position, fuel flows to the left filter. In the center
position (up), fuel flows to both filters. In the
right position (shown), fuel flows to the right filter. The duplex filter system is also equipped with a
primary differential fuel pressure switch (12), which is monitored by the Marine Classification
Society (MCS) control panel. When the switch is open, the control panel will display a warning.

The primary fuel filters are equipped with a water in fuel sensor (located at the bottom of the
fuel/water separator) that sends a signal to the control panel when there is water present in the
separator bowl. When the sensor detects water in the fuel, a warning is displayed on the control
panel.

When replacing a fuel filter, the fuel system must be primed prior to starting or cranking the engine.
Do not prefill new fuel filters prior to installation on the engine. Prefilling the filters can introduce
contaminants into the fuel system and cause damage.

Pump the plunger several times to prime the system. After priming the fuel system, there should be
sufficient fuel in the filters to allow the engine to start and run. Do not open any fuel lines during the
priming procedure.

The secondary fuel filter is a high efficiency

filter. All fuel entering the high pressure
section of the injection pump must pass
through the secondary filter.

The duplex filter system secondary fuel filter

base includes a control lever (3) that operates
the same as the control lever on the primary
fuel filter base. The duplex filter system is
also equipped with a secondary differential
fuel pressure switch (4), which is monitored
by the MCS control panel. When the switch is
open, the control panel will display a warning.

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The fuel pump assembly consists of a low pressure transfer pump and a high pressure fuel
injection pump. The pump assembly is driven from a gear in the front timing case at half engine
speed. The fuel injection pump has two pistons that are driven by a camshaft. There is a cam for
each piston and each cam has three lobes. The fuel injection pump delivers a volume of fuel six
times for each revolution. The stroke of the pistons is fixed. The injector will use only part of the
fuel that is delivered by each stroke of the pistons in the pump. The solenoid for the fuel injection
pump is controlled by the ECM in order to maintain the fuel manifold pressure at the correct level.
The solenoid allows excess fuel to be diverted away from the fuel manifold and back to the tank. A
feature of the fuel injection pump allows fuel to return to the tank continuously.

(1) Fuel Injection Pump

(2) Fuel Transfer Pump

The fuel output of the fuel injection pump is controlled by the ECM in response to changes in fuel
pressure.

The injection pump (2) and pump solenoid (3) are not serviceable. The injection pump is
serviceable as a unit. The transfer pump and the secondary speed/timing sensor (4) are the only
components serviced separately on the pump.

The fuel transfer pump provides a relatively low fuel pressure to the fuel injection pump. The fuel
transfer pump has a regulating valve in order to control the low pressure. The fuel transfer pump
circulates fuel through the primary fuel filter and the secondary fuel filter. The fuel transfer pump
has a fuel bypass valve in order to allow the low pressure fuel system to be primed.

The fuel injection pump must be timed to the

engine and the pump must be removed to be
timed. The fuel pump must also be locked
before removal. To lock the pump, loosen the
locking pin (5) and slide the washer (6) so that
the shoulder of the locking pin fits through the
larger hole in the washer. Tighten the locking
pin to the proper torque to lock the pump.

Fuel injection pump timing is necessary for two

reasons:

- The pump stroke must be in phase with

the fuel injection

- The speed/timing sensor must be timed with the engine

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Note : When the pump is removed, a special tool is required to ensure the fuel pump shaft is in the
correct position (timed to the engine).
Solenoid
Return Line to Tank
Fuel Inlet -HP

Fuel Outlet -HP

Fuel Injection Pump
Oil Inlet

Fuel Outlet -LP

Speed/Timing Sensor
Fuel Transfer Pump

Fuel Inlet -LP

The high pressure pump is lubricated by engine oil supplied by a pressure line from the left side
engine oil galley.

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The ECM determines the quantity, timing and pressure of the fuel in order to be injected into the
fuel injector.

The ECM uses input from the sensors on the engine. These sensors include the speed/timing
sensors and the pressure sensors.

The ECM controls the fuel pressure by increasing or decreasing the flow of fuel from the fuel
injection pump. The ECM controls the timing and the flow of fuel by actuating the injector solenoid.
The amount of fuel is proportional to the duration of the signal to the injector solenoid.

Fuel Injectors :

1. O-ring
2. Injector tip
3. Injector serial number
4. Confirmation code
5. Bar code

The fuel injectors are not serviceable.

When the ECM sends a signal to the injector solenoid, a valve inside the injector opens. The valve
allows the high pressure fuel from the fuel manifold to enter the injector. The pressure of the fuel
pushes the needle valve and a spring. When the force of the fuel pressure is greater than the force
of the spring, the needle valve will lift up.

The timing and duration of injection is

controlled by a solenoid valve in the
injector. The valve has two positions.
In the closed position, the valve closes
the inlet to the injector. In this position,
fuel above the injector needle is
allowed to vent through the leakoff
port.

In the open position, the valve opens

the inlet to the injector.
Simultaneously, the valve closes the
leakoff port in order to allow high
pressure fuel to flow to the needle.
When the solenoid valve is closed,
some fuel escapes past the valve in
order to vent through the leakoff port.
A certain volume of fuel always flows
from the leakoff port. If the volume of

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fuel increases beyond a critical level, the fuel injection pump will not be able to maintain pressure
in the fuel manifold. The faulty electronic unit injector must be identified and replaced.

When the signal to the injector ends, the valve closes. The fuel in the injector changes to a low
pressure. When the pressure drops the needle valve will close and the injection cycle stops. When
the needle valve opens, fuel under high pressure will flow through nozzle orifices into the cylinder.
The fuel is injected into the cylinder through the orifices in the nozzle as a very fine spray.

The needle valve has a close fit with the inside of the nozzle. This makes a positive seal for the
valve.

When replacing an injector, the following parts must also be replaced:

- Injector fuel line

- O-ring (1)
- Copper injector washer. The copper washer is installed at the top of the injector tip (2)
- Injector hold down bolt
- Injector pipe
- Rubber boot that seals the valve cover opening
- Valve cover gasket

When removing a fuel line and reusing an injector, always cap the injector immediately until ready
to install the new line. Then, finger tighten all lines and clamps first, and torque properly.

Do not over tighten the solenoid connections on top of the injector. Use the proper
torque specification in the service information.

Note : When removing an injector, move the intake rocker arms to gain access to the injector hold
down bolt. It is not necessary to remove the complete rocker arm shaft.

The injector serial number (3) and confirmation code (4) are used for trimming the injector. The bar
code (5) is used during injector production. Document the injector serial number and confirmation
code before installing a new injector.

Cat ET is used to flash the ECM with the proper injector trim file. The injector trim file can be found
on the CD that comes with the replacement injector.

The C6.6 ACERT has an “Adaptive Trim” (self-calibration) process that occurs approximately every
125 hours. The Adaptive Trim process ensures injection efficiency and trims each injector
accordingly. A slight audible change may be noticed, but the trim process has no effect on engine
performance.

If any of the injectors are out of tolerance, a diagnostic code will be set. The Fuel System
Verification Test in Cat ET can be used to manually perform the Adaptive Trim process, if
necessary.

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Fuel Manifold :

1. Common rail fuel manifold

2. Inlet fitting
3. Fuel injector supply lines
4. Fuel rail pressure sensor
5. Fuel pressure relief valve

The common rail fuel manifold (1) is

mounted to the rear of the inlet air manifold
on the left side of the engine. High pressure
fuel from the fuel injection pump enters the
common rail manifold at the inlet fitting (2).
The common rail manifold distributes the
high pressure fuel evenly to the six
“internally hardened” fuel injector supply
lines (3). The steel fuel lines pass through
the valve cover base and connect to individual fuel injectors.

Due to the unique “internally hardened” manufacturing process of the fuel injector supply lines, the
fuel lines must be replaced whenever they have been “cracked” or disconnected.

Note : Cracking or removing the fuel lines can disturb the internal hardening of the high pressure
fuel lines and the seal performance, which can cause the lines to fail. Failure of a high pressure
fuel line can result in a machine fire, personal injury or death. Order new genuine Caterpillar
replacement fuel lines whenever a fuel injector supply or high pressure pump output fuel line is
removed.

A fuel rail pressure sensor (4) is used to monitor the pressure of the common rail high pressure
fuel system. The Engine ECM will monitor the signal from the fuel rail pressure sensor and
maintain optimum fuel system pressure for any given load or temperature condition. The fuel rail
pressure sensor is serviceable separately from the fuel manifold.

A fuel pressure relief valve (5) is used to protect the high pressure fuel system from fuel pressure
spikes. The fuel pressure relief valve will start to open at 160 MPa (1600 bar) and withstand a
pressure spike of up to 190 MPa (1900 bar). When the fuel pressure relief valve opens, fuel is
returned to the fuel tank. The fuel pressure relief valve is not serviceable separately from the fuel
manifold. If the fuel pressure relief valve fails, the fuel manifold and associated parts must also be
replaced.

C6.6 generator sets that are required to receive an engine certification from any marine
classification society and fulfill the Safety of Lives at Sea (SOLAS) requirement, must be equipped
with double wall fuel lines. The double wall fuel lines include a return line (1) to the alarm reservoir
(2). The alarm tank (fuel leak off) switch (3) informs the MCS or EMCP3 control panel if excessive
fuel is present.

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Air Inlet and Exhaust System :

The components of the air inlet and exhaust system control the quality of air and the amount of air
that is available for combustion. The air inlet and exhaust system consists of the following
components:

 Air cleaner
 Turbocharger
 Aftercooler
 Inlet manifold
 Cylinder head, injectors and glow plugs
 Valves and valve system components
 Piston and cylinder
 Exhaust manifold

Air is drawn in through the air cleaner into the air inlet of
the turbocharger by the turbocharger compressor wheel.
The air is compressed and heated to about 150 °C before
the air is forced to the aftercooler. As the air flows through
the aftercooler the temperature of the compressed air
lowers to about 50 °C. Cooling of the inlet air increases
combustion efficiency. Increased combustion efficiency
helps achieve the following benefits:

 Lower fuel consumption

 Increased horsepower output
 Reduced particulate emission

From the aftercooler, air is forced into the inlet manifold. Air flow from the inlet manifold to the
cylinders is controlled by inlet valves. There are two inlet valves and two exhaust valves for each
cylinder. The inlet valves open when the piston moves down on the intake stroke. When the inlet
valves open, cooled compressed air from the inlet port is forced into the cylinder. The complete
cycle consists of four strokes:

 Inlet
 Compression
 Power
 Exhaust

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On the compression stroke, the piston moves back up the cylinder and the inlet valves close. The
cool compressed air is compressed further. This additional compression generates more heat.

Note: If the cold starting system is operating, the glow plugs will also heat the air in the cylinder.

Just before the piston reaches the TC position, the

ECM operates the electronic unit injector. Fuel is
injected into the cylinder. The air/fuel mixture ignites.
The ignition of the gases initiates the power stroke.
Both the inlet and the exhaust valves are closed and
the expanding gases force the piston downward
toward the bottom center (BC) position.

From the BC position, the piston moves upward. This

initiates the exhaust stroke. The exhaust valves
open. The exhaust gases are forced through the
open exhaust valves into the exhaust manifold.

Exhaust gases from exhaust manifold enter the

turbine side of the turbocharger in order to turn
turbocharger turbine wheel. The turbine wheel is
connected to the shaft that drives the compressor
wheel. Exhaust gases from the turbocharger pass
through exhaust outlet, a silencer and an exhaust pipe.

Turbocharger :

(1) Air intake (7) Turbine housing

(2) Compressor housing (8) Turbine wheel
(3) Compressor wheel (9) Exhaust outlet
(4) Bearing (10) Oil outlet port
(5) Oil inlet port (11) Exhaust inlet
(6) Bearing

The turbocharger is mounted on the outlet of the exhaust manifold. The exhaust gas from the
exhaust manifold enters the exhaust inlet (11). The gas then passes through the turbine housing
(7) of the turbocharger. Energy from the exhaust gas causes the turbine wheel (8) to rotate. The
turbine wheel is connected by a shaft to the compressor wheel (3) .

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As the turbine wheel rotates, the compressor wheel is rotated. This causes the intake air to be
pressurized through the compressor housing (2) of the turbocharger.

The shaft that connects the turbine to the compressor wheel rotates in bearings (4 and 6). The
bearings require oil under pressure for lubrication and cooling. The oil that flows to the lubricating
oil inlet port (5) passes through the center of the turbocharger which retains the bearings. The oil
exits the turbocharger from the lubricating oil outlet port (10) and returns to the oil pan.

Valve System Components :

(1) Bridge
(2) Rocker arm
(3) Pushrod
(4) Lifter
(5) Spring
(6) Valve

The valve system components control the flow of inlet

air into the cylinders during engine operation. The valve
system components also control the flow of exhaust
gases out of the cylinders during engine operation.

The crankshaft gear drives the camshaft gear through

an idler gear. The camshaft must be timed to the
crankshaft in order to get the correct relation between
the piston movement and the valve movement.

The camshaft has two camshaft lobes for each cylinder. The lobes operate either a pair of inlet
valves or a pair of exhaust valves. As the camshaft turns, lobes on the camshaft cause the lifter (4)
to move the pushrod (3) up and down. Upward movement of the pushrod against rocker arm (2)
results in a downward movement that acts on the valve bridge (1). This action opens a pair of
valves (6) which compresses the valve springs (5). When the camshaft has rotated to the peak of
the lobe, the valves are fully open. When the camshaft rotates further, the two valve springs (5)
under compression start to expand. The valve stems are under tension of the springs. The stems
are pushed upward in order to maintain contact with the valve bridge (1). The continued rotation of
the camshaft causes the rocker arm (2), the pushrods (3) and the lifters (4) to move downward until
the lifter reaches the bottom of the lobe. The valves (6) are now closed. The cycle is repeated for
all the valves on each cylinder.

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Lubrication System :

Oil pressure for the engine lubrication system is provided by an engine

mounted oil pump. The engine oil pump is located on the bottom of the
cylinder block and within the oil pan. Lubricating oil from the oil pan flows
through a strainer and a pipe to the inlet side of the engine oil pump. The
engine oil pump is driven from the crankshaft through an idler gear.

The engine oil pump has an inner rotor with four lobes. The inner rotor is
mounted to a shaft which also carries the drive gear. The engine oil pump
also has an outer annulus with five lobes. The axis of rotation of the annulus
is offset relative to the rotor. The distance between the lobes of the rotor
and the annulus increases on the right hand side when the rotor is rotated.
The increasing space between the lobes of the rotor and the annulus
causes a reduction in pressure. This reduction in oil pressure causes oil to
flow from the oil pan, through the oil strainer and into the oil pump.

The distance between the lobes of the rotor and annulus decreases
on the left hand side when the rotor is rotated. The decreasing
space between the lobes of the rotor and annulus causes oil to be
pressurized. The increase in oil pressure causes oil to flow from the
oil pump outlet into the engine lubrication system.

The oil flows from the pump through holes in the cylinder block to a
plate type oil cooler. The plate type oil cooler is located on the left
hand side of the engine.

From the oil cooler, the oil returns through a drilling in the cylinder block to the filter head.

The oil flows from the oil filter through a passage to the oil gallery. The oil
gallery is drilled through the total length of the left side of the cylinder
block. If the oil filter is on the right side of the engine, the oil flows through
a pipe assembly. The pipe assembly is mounted to the lower face of the
cylinder block.

Lubricating oil from the oil gallery flows through passages to the main bearings of the crankshaft.
The oil flows through the passages in the crankshaft to the connecting rod bearing journals. The
pistons and the cylinder bores are lubricated by the splash of oil and the oil mist.

Lubricating oil from the main bearings flows through passages in the cylinder block to the journals
of the camshaft. Then, the oil flows from the second journal of the camshaft at a reduced pressure
to the cylinder head. The oil then flows into the rocker arm bushing of the rocker arm levers. The
valve stems, the valve springs and the valve lifters are lubricated by the splash and the mist of the
oil.

The hub of the idler gear is lubricated by oil from the oil gallery. The timing gears are lubricated by
the splash of the oil.

The turbocharger is lubricated by oil via a drilled passage through the cylinder block. An external
line from the engine block supplies oil to the turbocharger. The oil then flows through a line to the
oil pan.

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Piston cooling jets are installed in the engine. The piston cooling
jets are supplied with the oil from the oil gallery. The piston cooling
jets spray lubricating oil on the underside of the pistons in order to
cool the pistons.

Engine Oil :

Caterpillar oils have been developed and tested in order to provide the full performance and
service life that has been designed and built into Caterpillar Engines. Caterpillar oils are currently
used to fill diesel engines at the factory. These oils are offered by Caterpillar dealers for continued
use when the engine oil is changed.

Due to significant variations in the quality and in the performance of commercially available oils,
Caterpillar makes the following recommendations:

 Cat DEO (Diesel Engine Oil) (SAE 10W-30)

 Cat DEO (Diesel Engine Oil) (SAE 15W-40)

Cat DEO Multigrade is formulated with the correct amounts of detergents, dispersants, and
alkalinity in order to provide superior performance in Caterpillar Diesel Engines.

Cat DEO Multigrade is available in various viscosity grades that include SAE 10W-30 and SAE
15W-40. To choose the correct viscosity grade for the ambient temperature, see the table.
Multigrade oils provide the correct viscosity for a broad range of operating temperatures.
Multigrade oils are also effective in maintaining low oil consumption and low levels of piston
deposits.

Note: Cat DEO in SAE 15W-40 exceeds the performance requirements for the following API
categories: CI-4, CH-4, CG-4, CF-4 and CF. Cat DEO Multigrade exceeds the requirements of the
Caterpillar Engine Crankcase Fluid-1 (ECF-1) specification. Cat DEO in SAE 15W-40 passes the
following proprietary tests: sticking of the piston ring, oil control tests, wear tests and soot tests.
Proprietary tests help ensure that Caterpillar multigrade oil provides superior performance in
Caterpillar Diesel Engines. In addition, Cat DEO Multigrade exceeds many of the performance
requirements of other manufacturers of diesel engines. Therefore, this oil is an excellent choice for
many mixed fleets. True high performance oil is produced with a combination of the following
factors: industry standard tests, proprietary tests, field tests and prior experience with similar
formulations. The design and the development of Caterpillar lubricants that are both high
performance and high quality are based on these factors.

Note: Non-Caterpillar commercial oils are second choice oils.

In order to select the correct engine oil for the marine C6.6 genset, you must refer to table.

API Classifications for the Marine C6.6 Genset

Engine Power Oil Specification Maintenance Interval

Less than
CH-4/CI-4 500 Hours
168 kW (225 hp)

More than
CI-4 500 Hours
168 kW (225 hp)

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Note : If Cat DEO Multigrade is not used, use only commercial oils that meet the following
categories.

 API CH-4 multigrade oils and API CI-4 multigrade oils are acceptable if the requirements of
Caterpillar's ECF-1 specification are met. CH-4 oils and CI-4 oils that have not met the
requirements of Caterpillar's ECF-1 specification may cause reduced engine life.

Note : When oil meets more than one API category, the applicable footnote is determined by the
highest API category that is met.

Example - An oil meets both the API CH-4 and the API CF oil categories. In this case, the API CH-
4 applies.

Note : In selecting oil for any engine application, both the oil viscosity and oil performance
category/specification as specified by the engine manufacturer must be defined and satisfied.
Using only one of these parameters will not sufficiently define oil for an engine application.

In order to make the proper choice of a commercial oil, refer to the following explanations:

API CI-4 - API CI-4 oils were developed in order to meet the requirements of high performance
diesel engines that use cooled Exhaust Gas Recirculation (EGR). API CI-4 oils are acceptable if
the requirements of Caterpillar's ECF-1 specification are met.

API CH-4 - API CH-4 oils were developed in order to protect low emissions diesel engines that use
a 0.05 percent level of fuel sulfur. However, API CH-4 oils may be used with higher sulfur fuels.
API CH-4 oils are acceptable if the requirements of Caterpillar's ECF-1 specification are met.

Note : CH-4 oils and CI-4 oils that have not met the requirements of Caterpillar's ECF-1
specification may cause reduced engine life.

Note : Failure to follow these oil recommendations can cause shortened engine service life due to
deposits and/or excessive wear.

The proper SAE viscosity grade of oil is determined by the minimum ambient temperature during
cold engine start-up, and the maximum ambient temperature during engine operation.

Refer to the table (minimum temperature) in order to determine the required oil viscosity for starting
a cold engine.

Refer to the table 2 (maximum temperature) in

order to select the oil viscosity for engine operation
at the highest ambient temperature that is
anticipated.

Note : Generally, use the highest oil viscosity that

is available to meet the requirement for the
temperature at start-up.

If ambient temperature conditions at engine start-

up require the use of multigrade SAE 0W oil, SAE
0W-40 viscosity grade is preferred over SAE 0W-
20 or SAE 0W-30.

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 Engine Oil Viscosities for Ambient Temperatures

Ambient Temperature

Viscosity Grade Minimum Maximum

SAE 0W-20
−40 °C 10 °C

SAE 0W-30
−40 °C 30 °C

SAE 0W-40
−40 °C 40 °C

SAE 5W-30
−30 °C 30 °C

SAE 5W-40
−30 °C 50 °C

SAE 10W-30
−18 °C 40 °C

SAE 10W-40
−18 °C 50 °C

SAE 15W-40
−9.5 °C 50 °C

Note: Supplemental heat is recommended below the minimum recommended ambient

temperature.

Total Base Number (TBN) and Fuel Sulfur Levels :

The use of Cat S·O·S Services oil analysis is recommended strongly for determining oil life.

The minimum required Total Base Number (TBN) for oil depends on the fuel sulfur level. The TBN
for new oil is typically determined by the "ASTM D2896" procedure. For direct injection engines
that use distillate fuel, the following guidelines apply:

TBN recommendations for applications in Cat Engines

(1)
Cat Engine Oils TBN of Commercial Engine Oils
Fuel Sulfur Level percent (ppm)

Cat DEO-ULS
0.05 percent (500ppm) Min 7
Cat DEO
(2)
>0.05-0.2 percent (>500- 2000 ppm) Cat DEO-ULS
Min 10
Cat DEO

Above 0.2 percent (above 2000ppm) (5)

(3) (4) Cat DEO Min 10

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(1) Cat DEO-ULS applies to Cat DEO-ULS SAE 15W-40, SAE10W-30 and Cat DEO Cold Weather SAE 0W-40. Cat
DEO applies to Cat DEO SAE 15W-40 and SAE 10W-30.
(2) Use of an oil analysis program to determine oil drain intervals is strongly recommended if fuel sulfur is between
0.05% (500 ppm) and 0.5% (5000 ppm).
(3)
Use of an oil analysis program to determine oil drain intervals is required if fuel sulfur is above 0.5% (5000 ppm).
(4) For fuels of sulfur levels that exceed 1.0 percent (10,000 ppm), refer to TBN and engine oil guidelines given in
Special Publication, SEBU6251, "Cat Commercial Diesel Engine Fluids Recommendations", "Engine Oil".
(5) Cat DEO-ULS may be used if an oil analysis program is followed. High fuel sulfur levels may reduce the oil drain
intervals.
SOS :

Caterpillar has developed a tool for maintenance management that

evaluates oil degradation and the tool also detects the early signs of
wear on internal components. The Caterpillar tool for oil analysis is
called S·O·S Oil Analysis and the tool is part of the S·O·S Services
program. S·O·S Oil Analysis divides oil analysis into three
categories:

 Wear Analysis
 Oil condition
 Additional tests

The wear analysis monitors metal particles, some oil additives, and
some contaminants.

Oil condition uses infrared (IR) analysis to evaluate the chemistry of

the oil. Infrared analysis is also used to detect certain types of
contamination.

Additional tests are used to measure contamination levels from

water, fuel, or coolant. Oil viscosity and corrosion protection can be
evaluated, as needed.

The refill capacities for the engine crankcase reflect the

approximate capacity of the crankcase or sump plus standard oil
filters. Duplex oil filter systems will require additional oil.

Engine Refill Capacities

Compartment or System Quantity

Crankcase Oil Sump (1)

17.5 L
(1) This value is the approximate capacities for the crankcase oil sump which includes the standard factory installed oil
filter. Engines with duplex oil filters will require additional oil.

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Cooling System :

(1) Aftercooler
(2) Purge line
(3) Exhaust manifold
(4) Water temperature
regulator housing
(5) Engine oil cooler
(6) Water pump
(7) Engine
(8) Keel cooler
(9) Keel cooler for aftercooler
(10) Auxiliary water pump
(11) Remote tank

During engine operation, water pump (6) draws engine coolant from keel cooler (8). The water
pump creates coolant flow through the system. The water pump is installed on the front of the
timing case. The water pump is gear-driven by the fuel injection pump gear.

Water pump (6) forces the coolant through a passage in the front of the timing case to the water
jacket in the top left side of the cylinder block. One-third of the coolant flows around the element of
oil cooler (5) to the rear of the cylinder block. Two-thirds of the coolant is used in order to cool the
cylinder block. The coolant continues to the rear of the cylinder block and the coolant is diverted to
the following locations:

 Exhaust manifold (3)

 Cylinder head

The coolant flows forward through the cylinder head and into
water temperature regulator housing (4). If the water temperature
regulator is closed, the coolant goes directly through a bypass to
the inlet side of water pump (6). If the water temperature regulator
is open, the bypass is closed and the coolant flows to keel cooler
(8) in order to be cooled. After the coolant flows through the keel
cooler, the coolant is mixed with coolant that is returning from
exhaust manifold (3) .

An auxiliary water pump (10) is also used in order to supply

coolant flow to aftercooler (1). The coolant flows through the
aftercooler in order to cool the hot inlet air. From the aftercooler,
the coolant flows to a second keel cooler (9) in order to be cooled.

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(1) Water Pump (2) Auxiliary Water Pump (3) Aftercooler

35 / 103
 (1) Coolant level gauge

(2) Sight glass

This illustration shows the remote mounted

expansion tank used on a keel cooling system.
The remote expansion tank is equipped with a
coolant level gauge (1) and a sight glass (2).

Coolant :

The following two coolants are used in Caterpillar diesel engines:

Preferred - Cat ELC (Extended Life Coolant) or a commercial extended life coolant that meets the
Caterpillar EC-1 specification

Acceptable - A Cat DEAC (Diesel Engine Antifreeze/Coolant) or a commercial heavy-duty

antifreeze that meets "ASTM D4985" or "ASTM D5345" specifications

Note : Do not use a commercial coolant/antifreeze that only meets the ASTM "D3306"
specification. This type of coolant/antifreeze is made for light duty automotive applications.
Use only the coolant/antifreeze that is recommended.

Caterpillar recommends a 1:1 mixture of water and glycol. This mixture of water and glycol will
provide optimum heavy-duty performance as an antifreeze.

Note: Cat DEAC does not require a treatment with

an SCA at the initial fill. Commercial heavy-duty
antifreeze that meets "ASTM D4985" or "ASTM
D5345" specifications MAY require a treatment
with an SCA at the initial fill. Read the label or the
instructions that are provided by the OEM of the
product.

In stationary engine applications that do not

require anti-boil protection or freeze protection, a
mixture of SCA and water is acceptable.
Caterpillar recommends a six percent to eight
percent concentration of SCA in those cooling
systems. Distilled water or deionized water is
preferred. Water which has the recommended
properties may be used.

36 / 103
 Coolant Service Life

Coolant Type Service Life

Cat ELC 6000 Service Hours or Six Years

3000 Service Hours or Three Years

Cat DEAC

Commercial Heavy-Duty Antifreeze that meets "ASTM 3000 Service Hours or Two Years
D5345"

Commercial Heavy-Duty Antifreeze that meets "ASTM

3000 Service Hours or One Year
D4985"

3000 Service Hours or Two Years

Caterpillar SCA and Water

Commercial SCA and Water 3000 Service Hours or One Year

Refill Capacities

Engine Cooling System Quantity

Sea water cooled. 30 L

37 / 103
S·O·S Coolant Analysis :

Recommended Interval

Type of Coolant Level 1 Level 2

DEAC Every 250 Hours Yearly (1)

ELC Not Required Yearly

(1) The Level 2 Coolant Analysis should be performed sooner if a problem is identified by a Level 1 Coolant Analysis.

S·O·S Coolant Analysis (Level 1)

A coolant analysis (Level 1) is a test of the properties of the coolant.

The following properties of the coolant are tested:

 Glycol concentration for freeze protection and boil protection

 Ability to protect from erosion and corrosion
 pH
 Conductivity
 Visual analysis
 Odor analysis

The results are reported, and appropriate recommendations are made.

S·O·S Coolant Analysis (Level 2)

A coolant analysis (Level 2) is a comprehensive chemical evaluation

of the coolant. This analysis is also a check of the overall condition of
the inside of the cooling system.

The S·O·S Coolant Analysis has the following features:

 Full coolant analysis (Level 1)

 Identification of the source of metal corrosion and of
contaminants
 Water hardness
 Identification of buildup of the impurities that cause corrosion
 Identification of buildup of the impurities that cause scaling

The results are reported, and appropriate recommendations are made.

Testing the engine coolant is important to ensure that the engine is protected
from internal cavitation and from corrosion. The analysis also tests the ability
of the coolant to protect the engine from boiling and from freezing.

38 / 103
Electronic System :

(1) Coolant Temperature Sensor (6) Primary Speed/Timing Sensor

(2) Intake Manifold Air Temperature Sensor (7) Electronic Control Module (ECM)
(3) Intake Manifold Pressure Sensor (8) Overspeed (Magnetic Pickup)
(4) Fuel Pressure Sensor (9) Secondary Speed/Timing Sensor
(5) Oil Pressure Sensor

39 / 103
(1) Coolant Temperature Sensor (4) Fuel Pressure Sensor
(2) Intake Manifold Air Temperature Sensor (5) Oil Pressure Sensor
(3) Intake Manifold Pressure Sensor

(6) Primary Speed/Timing Sensor (8) Overspeed (Magnetic Pickup)

(7) Electronic Control Module (ECM) (9) Secondary Speed/Timing Sensor

40 / 103
 (1) Coolant Level Switch (3) High Coolant Temperature Switch (Shutdown)
(2) Coolant Pressure Sender (Alarm) (4) High Coolant Temperature Transmitter (Alarm)

Coolant Level Switch 1 : The coolant level switch is powered from the panel. An alarm can be
activated by a signal from the coolant level switch. There are two different types of coolant level
switch. One switch is designed to be used on an expansion tank. The other switch is design in
order to be used on a radiator.

Coolant Pressure Sender 2 : The coolant pressure sender is powered from the panel. If an
incorrect signal is received, an alarm will be activated by the control panel when a signal is
received from the coolant pressure sender.

High Coolant Temperature Switch (Shutdown) 3 : A signal will be sent to the panel if high
coolant temperature occurs.

High Coolant Temperature Transmitter 4 : The coolant temperature transmitter is powered from
the panel. The transmitter can shut down the engine.

Fuel Pressure Switch 5 : The fuel pressure switch is powered by the panel.

(5) Fuel Pressure Switch

(6) Primary Fuel Differential
Pressure Switch (Alarm)
(7) Secondary Fuel
Differential Pressure Switch
(Alarm)
(8) Water Separator Switch
(Alarm)

41 / 103
Primary Fuel Differential Pressure Switch 6 : The inlet pressure and the outlet pressure of the
primary fuel filter is monitored.

Secondary Fuel Differential Pressure Switch 7 : The inlet pressure and the outlet pressure of
the secondary fuel filter is monitored.

Water Separator Switch 8 : The switch will operate if water is present in the bottom of the filter.

Alarm Tank Switch 9 : If the high pressure fuel line should rupture the tank will fill with fuel and
the switch will be operated.

Note: This switch can be installed on an engine that is equipped with the EMCP3 control panel.

(9) Alarm Tank Switch (12) Oil Filter Differential Pressure Switch (Alarm)
(10) Oil Pressure Shutdown switch (13) Oil Temperature Sender (Alarm)
(11) Oil Pressure Transmitter (Alarm)

Oil Pressure Switch 10 Shutdown : The oil pressure switch can send a signal to the control
panel in order to shut down the engine.

Oil Pressure Transmitter 11 : The oil pressure transmitter is powered from the panel. If an
incorrect signal is received, an alarm will be activated by the control panel when a signal is
received from the oil pressure transmitter.

Oil Filter Differential Pressure Switch12 : The inlet pressure and the outlet pressure of the oil
filter is monitored.

Oil Temperature Sender 13 : The sender will signal the panel if high oil temperature occurs.

Note: The magnetic pickup is used in order to shut down the engine if an overspeed condition
occurs.

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 (1) Primary engine speed/timing sensor

(2) Engine oil pressure sensor

Primary engine speed data is provided by the primary engine speed/timing sensor (1), or crank
speed/timing sensor. The primary engine speed/timing sensor is located at the left rear of the
engine block. Failure of the primary engine speed sensor while the engine is running will cause the
Engine ECM to look at the secondary speed/timing sensor (located on the fuel injection pump) for
engine speed information. The engine will continue to run using only the secondary speed/timing
sensor signal for engine rpm, and a fault code will be displayed. If the secondary speed/timing
sensor fails, the engine may not restart since the Engine ECM uses the secondary speed/timing
sensor as the reference for starting the engine.

The engine oil pressure sensor (2) is also located on the left side of the cylinder block. The sensor
is installed in the left engine oil galley. Low engine oil pressure, sensor failure, or wiring failure will
not result in an engine derate or shutdown but will cause a fault to be logged in the Engine ECM.

The status of the primary engine speed sensor and the engine oil pressure sensor can be viewed
with Cat ET.

(1) Inlet air temperature sensor

(2) Inlet air pressure (boost) sensor

The inlet air temperature sensor (1) and

the inlet air pressure (boost) sensor (2)
are installed in the inlet air manifold on
the left front of the engine.

The inlet air temperature sensor is a passive two-wire sensor and is an input to the Engine ECM.
The signals from the inlet air temperature sensor and the coolant temperature sensor are used to
determine engine starting aid requirements and to trim (adjust) injector pulse width as engine
operating temperatures change.

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The inlet air pressure sensor is an active three-wire sensor. The Engine ECM will use the signal
from this sensor to determine boost pressures supplied by the turbocharger. The air inlet pressure
sensor is used with the Engine ECM to control the air/fuel ratio electronically. This feature allows
very precise smoke control, which was not possible with mechanically governed engines.

Note : The inlet air pressure sensor also acts as an atmospheric pressure sensor by taking a snap
shot of atmospheric pressure when the key start switch is first turned to the on position. The other
engine sensors are also calibrated to the boost sensor atmospheric pressure reading.

The status of the inlet air temperature sensor and the inlet air pressure sensor can be viewed with
Cat ET.

(1) Coolant temperature sensor

(2) Cylinder head

(3) Water pump

The coolant temperature sensor (1) is

installed in the front left corner of the
cylinder head (2) near the water pump
(3). The coolant temperature sensor is
a “passive” two-wire thermistor type
sensor that sends a signal to the
Engine ECM indicating coolant
temperature.

(1) Coolant Pressure Sensor

(2) Coolant Temperature Switch

(Shutdown)

(3) Coolant Temperature Switch

(Alarm)

The coolant pressure sensor (1) is

powered by the MCS controller. The
coolant pressure sensor is a two-wire
sensor that sends a signal to the MCS
controller indicating coolant pressure.
If the coolant pressure is out of range,
the MCS control panel will activate an
alarm.

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 The coolant temperature switch (2) at
the rear right side of the engine
provides an indication to the MCS
controller if the coolant temperature is
too high. The coolant temperature
switch is a two-wire switch with a 270
ohm resistor. The MCS controller can
shut down the engine when the coolant
temperature switch is activated.

The coolant temperature switch (3) at

the front right side of the engine is a
two-wire switch that provides an
indication to the MCS controller if the
coolant temperature is too high. If the
coolant temperature switch is activated,
the MCS control panel will activate an
alarm.

(1) Fuel Pressure Sensor

(2) Secondary Fuel Differential

Pressure Switch

(3) Primary Fuel Differential Pressure

Switch

The fuel pressure sensor (1) is a two-

wire sensor that sends a signal to the
MCS controller indicating fuel pressure.
If the fuel pressure is out of range, the
MCS control panel will activate an
alarm.

The secondary fuel differential pressure

switch (2) and primary fuel differential
pressure switch (3) are two-wire
switches that monitor fuel filter
restriction. If a fuel filter is restricted, the
respective differential pressure switch is
activated and the MCS control panel
activates an alarm.

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 The water in fuel sensors (arrows) are
three-wire sensors that send a signal
to the MCS controller when there is
water present in the separator bowl.
When the sensor detects water in the
fuel, the MCS control panel activates
an alarm. There is a water in fuel
sensor installed in each primary fuel
filter.

The alarm tank (fuel leak off) switch

(arrow) is a two-wire switch that
informs the MCS controller if
excessive fuel is present. When the
alarm tank switch is activated, the
MCS control panel activates an alarm.

(1) Oil Pressure Switch (Shutdown)

(2) Oil Pressure Switch (Alarm)

The oil pressure switch (1) provides an

indication to the MCS controller if the oil
pressure is out of range. The oil pressure
switch is a two-wire switch with a 270 ohm
resistor. The MCS controller can shut down
the engine when the oil pressure switch
is activated.

The oil pressure switch (2) is a two-wire switch that provides an indication to the MCS controller if
the oil pressure is out of range. If the oil pressure out of range switch is activated, the MCS control
panel will activate an alarm.

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 (1) Oil Differential Pressure Switch

The oil differential pressure switch (1)

is a two-wire switch that monitors oil
filter restriction. If an oil filter is
restricted, the differential pressure
switch is activated and the MCS
control panel activates an alarm.

(2) Oil Temperature Switch

The oil temperature switch (2) is a

three-wire switch that is powered by
the MCS controller. An alarm can be
activated by a signal from the oil
temperature switch if the oil
temperature is out of range.

The engine speed (overspeed) sensor

(arrow) is located on the flywheel
housing on the left side of the engine
and sends a signal to the MCS
controller indicating engine speed. The
MCS controller can shut down the
engine when the generator set is
overspeeding.

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 A. Power Supply :

A1. Active Sensors

A2. Passive Sensors

B. Signal :

B1. Analog Sensors

B2. Digital Sensors

A1. Active Sensors :

Press.
Sensor
With
3
Cables

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A2. Passive Sensors :

Temp.
Sensor
With
2
Cables

B1. Analog Sensors :

Analog Signal

Analog Sinyal
Signal

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B2. Digital Sensors :

SIGNAL
DIGITAL SIGNAL

Sensor Types : 1 – Pressure Sensors

2 – Temperature Sensors

3 – Position Sensors

4 – Speed Sensors

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1- Pressure Sensors :

2 – Temperature Sensors :

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3 – Position Sensors :

Analog Position Sensor PWM Position Sensor

4 – Speed Sensors :

Sensor Failures :

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The electronic control system has the following components:

 Electronic unit injectors (1)

 The solenoid for the fuel injection pump (2)
 Secondary speed/timing sensor (3)
 Fuel injection pump (4)
 Primary speed/timing sensor (5)
 Intake manifold pressure sensors (6)
 Fuel rail pressure sensor (7)
 Engine oil pressure sensor (8)
 Intake manifold temperature sensor (9)
 Coolant temperature sensor (10)
 Diagnostic connector (11)
 ECM (12)

The C6.6 marine generator set was designed for electronic control. The engine has an Electronic
Control Module (ECM), a fuel injection pump and electronic unit injectors. All of these items are
electronically controlled. There are also a number of engine sensors. The ECM controls the engine
operating parameters through the software within the ECM and the inputs from the various
sensors. The software contains parameters that control the engine operation. The parameters
include all of the operating maps and customer selected parameters.

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This diagram shows the components of the C6.6 engine electronic control system that are
connected to the J2 engine harness. The sensors shown on the right provide the Engine ECM with
input that controls the fuel injectors (1) and fuel pump (2). The Engine ECM (3) has two 64-pin
sockets connecting to the engine harness (J2) and control panel harness (J1).

The engine electronic control system primarily performs the engine fuel control function. A solenoid
on each injector receives an ON/OFF signal from the Engine ECM that triggers the timing and
amount of fuel delivered to the combustion chamber. The engine electronic control system also
monitors other functions that are critical for engine performance, such as lubrication, combustion
air, and cooling.

C6.6 Engine ECM Input Component Specifications:

- Secondary Engine Speed/Timing Sensor (4) - active sensor, 2-wire Hall --effect
- Primary Engine Speed/Timing Sensor (5) - active sensor, 2-wire Hall effect –
- Fuel Rail Pressure Sensor (6) - active 5V supply; 3-wire; rated to 270 MPa
- Intake Manifold (Boost) Pressure Sensor (7) - active 5V supply; 3-wire; rated --to 339 kPa
ABSOLUTE (kPaA)
- Intake Manifold Air Temperature Sensor (8) - passive; 2-wire; minimum --temperature -
40°C, maximum temperature 150°C
- Engine Coolant Temperature Sensor (9) - passive; 2-wire; minimum --temperature -40°C,
maximum temperature 150°C
- Engine Oil Pressure Sensor (10) - active 5V supply; 3-wire; rated to 882 kPa -
ABSOLUTE (kPaA)

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C6.6 Engine ECM Output Component Specifications:

- Fuel Injectors (1) - 70 V supply

- Fuel Pump Solenoid (2) - 70 V supply -

Connector Function

P1 Machine Harness to ECM Connector (64 Pin Connector)

P2 Engine Harness to ECM Connector (64 Pin Connector)

P532 Fuel Rail Pump Solenoid Connector (2 Pin Connector)

P402 Secondary Speed/Timing Sensor (2 Pin Connector)

P401 Primary Speed/Timing Sensor (2 Pin Connector)

P201 Engine Oil Pressure Sensor (3 Pin Connector)

P228 Fuel Rail Pressure Sensor (3 Pin Connector)

P200 Intake Manifold Pressure Sensor (3 Pin Connector)

P103 Intake Manifold Temperature Sensor (2 Pin Connector)

P100 Coolant Temperature Sensor (2 Pin Connector)

J23 Diagnostic Connector

P691/J691 Electronic Unit Injectors for No. 1 and No. 2 Cylinders (4 Pin Connector)

P692/J692 Electronic Unit Injectors for No. 3 and No. 4 Cylinders (4 Pin Connector)

P693/J693 Electronic Unit Injectors for No. 5 and No. 6 Cylinders (4 Pin Connector)

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ECM :
The Electronic Control Module (ECM) (1) functions as a governor
and a computer for the fuel system. The ECM receives signals from
the sensors in order to control the timing and the engine speed.

The electronic system consists of the ECM, the engine sensors and
inputs from the parent machine. The ECM is the computer. The
personality module is the software for the computer. The
personality module contains the operating maps. The operating
maps define the following characteristics of the engine:

 Engine power
 Torque curves
 Engine speed (rpm)
 Engine Noise
 Smoke and Emissions

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 (1) Control panel harness connector (J1)

(2) Engine harness connector (J2)

(3) Grounding strap

(4) Anti-vibration mounts

The ECM has an excellent record of reliability. Any problems in the system are most likely to be the
connectors and the wiring harness. The ECM should be the last item in troubleshooting the engine.

The programmable software contains all the fuel setting information. The information determines
the engine performance.

The electronic controls determine the injection timing, the amount of fuel that is delivered to the
cylinders and the intake manifold pressure. These decisions are based on the actual conditions
and the desired conditions at any given time.

The governor has software that compares the desired engine speed to the actual engine speed.
The actual engine speed is determined through the primary speed/timing sensor and the
secondary speed/timing sensor. If the desired engine speed is greater than the actual engine
speed, the governor injects more fuel in order to increase engine speed.

Once the governor has determined the amount of fuel that is required, the software must determine
the timing of the fuel injection. Fuel injection timing is determined by the ECM after considering
input from the following components:

 Engine coolant temperature sensor

 The sensor for the intake manifold air temperature
 The sensor for the intake manifold pressure

At start-up, the ECM determines the top center position of the number 1 cylinder from the
secondary speed/timing sensor in the fuel injection pump. The ECM decides when fuel injection
should occur relative to the top center position. The ECM optimizes engine performance by control
of each of the electronic unit injectors so that the required amount of fuel is injected at the precise
point of the engine's cycle. The electronic unit injectors are supplied high pressure fuel from the
fuel manifold. The ECM also provides the signal to the solenoid in the fuel injection pump. The
solenoid in the fuel injection pump controls a valve in the fuel injection pump. This valve controls
the pressure in the fuel manifold. Fuel that is not required for the engine is diverted away from the
fuel injection pump back to the fuel tank.

The ECM adjusts injection timing and fuel pressure for the best engine performance, the best fuel
economy and the best control of exhaust emissions. The actual timing can be viewed with an
electronic service tool. Also, the desired timing can be viewed with an electronic service tool.
The programmable software inside the ECM sets certain limits on the amount of fuel that can be
injected.

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The FRC Limit is a limit that is based on intake manifold air pressure and engine rpm. The FRC
Limit is used to control the air/fuel ratio in order to control the engine's exhaust emissions. When
the ECM senses a higher intake manifold air pressure, the ECM increases the FRC Limit. A higher
intake manifold air pressure indicates that there is more air in the cylinder. When the ECM
increases the FRC Limit, the ECM allows more fuel into the cylinder.

The Rated Fuel Limit is a limit that is based on the power rating of the engine and on the engine
rpm. The Rated Fuel Limit enables the engine power and torque outputs to conform to the power
and torque curves of a specific engine model.

These limits are in the programmable software and these limits cannot be changed.

When the ECM detects an electronic system problem, the ECM generates a diagnostic code. Also,
the ECM logs the diagnostic code in order to indicate the time of the problem's occurrence.

The ECM also logs the number of occurrences of the problem. Diagnostic codes are provided in
order to indicate that the ECM has detected an electrical problem or an electronic problem with the
engine control system. In some cases, the engine performance can be affected when the condition
that is causing the code exists.

If the operator indicates that a performance problem occurs, the diagnostic code may indicate the
cause of the problem. Use a laptop computer to access the diagnostic codes. The problem should
then be corrected.

Event Codes are used to indicate that the ECM has detected an abnormal engine operating
condition. The ECM will log the occurrence of the event code. This does not indicate an electrical
malfunction or an electronic malfunction. If the temperature of the coolant in the engine is higher
than the permitted limit, then the ECM will detect the condition. The ECM will then log an event
code for the condition.

The primary engine position is a passive sensor. The timing wheel is located on the crankshaft.
The speed/timing sensor receives a signal from the teeth on timing wheel. The extra space on the
timing wheel gives one revolution per space. The space is oriented so that the space is 40 degrees
after top center.

When the engine is cranking, the ECM uses the signal from the speed/timing sensor in the fuel
injection pump. When the engine is running the ECM uses the signal from the speed/timing sensor
on the crankshaft. This speed/timing sensor is the primary source of the engine position.

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The boost pressure sensor and the engine oil pressure sensor are active sensors. The boost
pressure sensor provides the ECM with a measurement of intake manifold pressure in order to
control the air/fuel ratio. This will reduce the engine smoke during transient conditions.

The engine oil pressure sensor provides the ECM with a measurement of engine oil pressure. The
ECM can warn the operator of possible conditions that can damage the engine. This includes the
detection of an oil filter that is blocked.

The air intake temperature sensor and the coolant temperature sensor are passive sensors. Each
sensor provides a temperature input to the ECM. The ECM controls following operations:

 Fuel delivery
 Injection timing

The sensors are also used for engine monitoring.

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The C6.6 marine generator set supplies power to the ECM.

The ECM powers the following components:

 All sensors on the engine

 The solenoid for the fuel injection pump
 Diagnostic connector
 Electronic unit injectors

The glow plugs are powered directly from the battery.

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Marine Classification Society (MCS) Control Panel :

(1) Engine shutdown override switch (7) Diagnostic connector

(2) Reset button (8) Emergency stop push button
(3) Backup start/stop switch (9) Control panel
(4) Connector C (31 way) (10) AC connector
(5) Connector B (21 way) (11) Isolator Keyswitch
(6) Connector A (23 way)

The power for the panel is supplied by the isolator keyswitch.

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(1) Controller (15) k1 key
(2) Capacitor (16) Gland plate for customer connections
(3) K5 relay (17) Gland for customer connection
(4) S PWM converter (18) Audible alarm connector
(5) Additional magnetic speed pickup (19) Engine shutdown override switch
(6) B- PWM converter (20) Reset switch
(7) B+ PWM converter (21) Backup start/stop switch
(8) Alarm for the power failure mode (22) K4 relay
(9) Engine running output relay (23) K3 relay
(10) +ve supply (backup) (24) K2 relay
(11) -ve supply (25) 10 ampere circuit breaker
(12) +vemain supply (26) 10 amp circuit breaker
(13) Remote stop switch "remove link if supplied" (27) 10 amp circuit breaker
(14) Ground

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(1) Alarm indicator (15) Indicator lamp for control in remote mode
(2) Display (16) "MODE" key
(3) "LOG" (17) Indicator lamp for the status of the generator
(4) "VIEW" (18) Engine operating indicator
(5) Menu key for UP (19) "STOP" key (reset)
(6) Indicator lamp for the power status of the controller(20) "START" key
(7) Indicator lamp for the status of the controller (21) "JUMP" key
(8) Alarm indicator (22) Emergency stop push button
(9) Menu key for RIGHT (23) Maintenance clear switch
(10) Menu key for SELECT (24) Maintenance indicator lamp
(11) Lamp test switch (25) Diagnostic lamp
(12) Menu key for DOWN (26) Warning lamp for the ECM
(13) "BACK" key (27) Lamp for the shutdown override mode
(14) Menu key for LEFT (28) "INFO" key

The MCS control system is used for monitoring and controlling many of the generator set functions.
The MCS control system meets MCS requirements for manned and unmanned engine rooms,
including emergency applications, and comes with certification documentation.

The MCS control system is factory tested with alarms and shutdowns as required by the marine
societies requirements. The alarms are:

- Low oil pressure (alarm and shutdown)

- High oil temperature
- High coolant temperature (alarm and shutdown)
- Low coolant level
- Low coolant pressure
- Overspeed (alarm and shutdown)
- High pressure fuel leak
- Fuel filter differential pressure

Customer supplied switch inputs are required for low fuel tank level and low starting air pressure.

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The MCS control system includes an engine shutdown override (harbor) switch that toggles the low
oil pressure and high water temperature shutdowns on or off, to allow the customer to select an
emergency configuration or a non-emergency configuration (harbor use).

(1) Information display (7) Shutdown override mode lamp

(2) Emergency stop button (8) Alarm indicator
(3) Maintenance clear switch (9) Right side panel indicators
(4) Maintenance indicator lamp (10) Engine operating indicator
(5) Diagnostic lamp (11) Generator operating indicator
(6) Engine ECM warning lamp (12) Remote mode indicator

The MCS control panel contains an information display (1), an emergency stop button (2), and
several indicators and keys.

The maintenance clear switch (3) and the following indicators are on the left side of the panel:

- Maintenance indicator lamp (4)

- Diagnostic lamp (5)
- Engine ECM warning lamp (6)
- Shutdown override mode lamp (7)

The alarm indicator (8) flashes if alarms that have not been acknowledged are still present.
The indicators (9) on the right side of the panel from top to bottom are:

- Controller power
- Controller self-check
- Controller alarm inhibit

The engine operating indicator (10) illuminates when the generator is running and the generator
operating indicator (11) illuminates when the voltage and frequency are correct.

The remote mode indicator (12) illuminates when the remote mode is active.

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 (1) Info Key (6) Navigation Keys
(2) Jump Key (7) Lamp Test Switch
(3) Start Key (8) Back Key
(4) Stop Key (9) Mode Key
(5) View Key (10) Log Key

The INFO key (1) displays the list of alarms. The JUMP key (2) allows the user to enter a number
to select a menu. The START key (3) initiates the generator set starting sequence. The STOP key
(4) shuts down the engine and bypasses the cool down period.

The VIEW key (5) allows the user to enter a number to select a menu.

The navigation keys (6) are used to navigate through the various menus or monitoring screens,
and the up and down keys also increase or decrease the setpoint values. The select key, in the
center of the navigation keys, is used to select the function that has been chosen.

The lamp test switch (7) illuminates the LED indicators and the display screen.

The BACK key (8) moves one step back in the menu to the previous display.

The MODE key (9) switches the MCS control system between local start/stop and remote
start/stop.

The LOG key (10) shifts the display to the three lower lines to show the event and a list of alarms.
The list holds 100 events. These events are erased when the control panel is turned off.

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(1) MCS Controller (8) Indicators
(2) Diagnostic Connector (9) 10 Amp Circuit Breakers
(3) 23-Pin Engine Connector A (10) Relays
(4) 21-Pin Power Connector B (11) Backup Start/Stop Switch
(5) 31-Pin Customer Connector C (12) Reset Switch
(6) 9-Pin RS232 Cable (13) Engine Shutdown Override Switch
(7) Display Cable

The MCS controller (1) receives input information from the generator, the engine alarm switches
and sensors, and the engine shutdown switches and sensors. The controller processes the
information and sends corresponding output signals to control the display panel functions. The
controller also sends output signals to control the generator set starting/stopping function, the glow
plug relay, the remote alarm, and any other output devices.

The Cat ET service tool can be connected to the diagnostic connector (2) located on the side of the
control panel cabinet. Other connectors on the side of the cabinet are:

 23-pin engine connector A (3)

 21-pin power connector B (4)
 31-pin customer connector C (5)

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 Note : In the MCS control system, Cat ET can be connected to the Engine ECM through the
Cat and CAN data links. Caterpillar Utility software, loaded on a computer, is the electronic
service tool used for diagnosis and programming the MCS controller.

A standard 9-pin RS232 cable (6) is used to connect a computer with Caterpillar Utility software to
the MCS controller.

The display cable (7) connects the controller to the MCS display panel.

The indicators (8) on the controller from left to right are:

 Controller power
 Controller self-check
 Controller alarm inhibit

Three 10 amp circuit breakers (9) and five relays (10) are located inside the cabinet. Near the
bottom of the cabinet is the backup start/stop switch (11), the reset switch (12), and the engine
shutdown override switch (13).

The decal on the inside of the cabinet door shows the internal and external component layout.

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 (1) Generator Connector (2) Two Amp Generator Circuit Breakers

The generator connector (1) is located on the right side of the MCS control panel cabinet. Also
visible in this illustration are the two amp generator circuit breakers (2).

The MCS control panel is operated by keys on the control panel. The keys (4), (5), and (10) control
the starting and the stopping of the generator set. The keys (2), (3), (12), (13), (14), (15), (16), (20),
(21), and (22) allow the operator to access additional information about the generator set.

Alarm Indicator (1) - A flashing LED indicates that alarms that have not been acknowledged are
still present. A fixed LED indicates that all alarms are acknowledged. A red LED indicates
shutdown. A green LED is for an alarm.

Display Area (2) - The display area shows information about the generator set.

"LOG" Key (3) - This key shifts the display to the three lower lines in order to show the event and
a list of alarms. The list holds 100 events. These events are erased when the main unit is switched
off.

"VIEW" Key (4) - Enter a menu number selection. All settings have a specific number. The "VIEW"
key enables the user to select any setting. The "VIEW" key enables the user to display any setting
without navigating through all of the menus.

Menu Key for UP (5) - This key increases the value of the selected set point in the setting menus.
This key is also used for scrolling to the second line that displays the values for the generator in
the display for daily use.

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Indicator for Status of the Controller (7) - This light indicates that the unit is running a self-check
and the unit is functioning properly.

Indicator Light for "Alarm Inhibit" (8) - This light indicates that the "inhibit input" is on.

Menu Key for RIGHT (9) - This key moves the cursor to the right in order to maneuver in the
menus.

"SEL" Key (10) - This key is used to select the function that has been chosen. The function that
has been chosen is the underlined selection in the lower line of the display.

Lamp Test Switch (11) - The lamp test switch is used to test indicators on the control panel.

Menu Key for DOWN (12) - This key decreases the value of the selected set point in the setting
menus. This key is also used for scrolling to the second line that displays the values for the
generator in the display for daily use.

"BACK" Key (13) - The "BACK" key jumps one step backward in the menu to previous display or
to the entry screen.

Menu Key for LEFT (14) - This key moves the cursor to the left for maneuvering in the menus.

Indicator Light for Control in Remote Mode (15) - The indicator illuminated through operation of
Mode key. (12)

"MODE" Key (16) - The "MODE" key switches the system between LOCAL START/STOP and
"REMOTE START/STOP". Light (13) is illuminated for "REMOTE" control.

Generator Status Indicator (17) - This light indicates that the voltage and frequency is present
and OK.

Engine Operating Indicator (18) - Light indicates that the generator is running.

"STOP" Key (reset) (19) - The "STOP" key shuts down the engine when the engine is running.
Pressing the "STOP" key bypasses the cooldown period.

"START" Key (20) - The "START" key begins the starting sequence. The PPU must be in manual
mode in order for the "START" key to function. The remote indicator light (15) can not be
illuminated. To switch off the remote indicator light, press "MODE" key (14) .

"JUMP" Key (21) - The "JUMP" key is used to enter a number in order to select a menu. Every
setting has a specific number. Use the "JUMP" key in order to select any setting and display any
setting without navigating all the way through the menus.

Emergency Stop Push Button (22) - The emergency stop push button is used to shut down the
engine in an emergency situation.

Maintenance Clear Switch (23) - After the appropriate maintenance has been performed, the
maintenance clear switch is pushed in order to reset the maintenance lamp.

Maintenance Indicator Lamp (24) - This lamp will illuminate in order to indicate that the engine
requires maintenance to be performed.

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Diagnostic Lamp (25) - The diagnostic lamp will illuminate when a diagnostic code has been
generated by the Electronic Control Module (ECM).

Warning Lamp for the ECM (26) - This lamp will illuminate when the engine ECM indicates a fault
within the system. The engine will not start if the warning lamp for the ECM is illuminated.

Lamp for the Shutdown Override Mode (27) - This is illuminated when the engine shutdown
override switch inside the control panel has been set to the override setting. This lamp will
illuminate in order to indicate that the engine shutdown will occur if an overspeed condition occurs.
All other normal override parameters are ignored.

"INFO" Key (28) - This shifts the display in order to show the list of alarms. The list has a
maximum of 30 alarms. A history that displays the last 30 alarms can be viewed.

Setting the Password :

Setting the password can only be accomplished by using the "JUMP" key.

Note: Keep a record of the password. If the password is forgotten, it will not be possible to enter
the menus.

Use the following procedure to change the password.

1. Press the "JUMP" key.

2. Use the Menu key for UP and the Menu key for DOWN In order to step to channel 4976.
3. Press the "SEL" key.

Note: The password must be re-entered when the display has not been used for 3 minutes.

Service Menu :

Accessing the Service Menu can only be accomplished by using the "JUMP" key.

Use the following procedure to access the Service Menu.

1. Press the "JUMP" key.

2. Use the Menu key for UP and the Menu key for DOWN In order to step to channel 4980.
3. Press the "SEL" key.
4. Choose the desired functions, timers, inputs or outputs by moving the cursor and pressing
the "SEL" key.

Language Selection :

The MCS can be configured for the following languages: English, Spanish, German and French.
The language may be chosen when the system is set up. The language may be chosen by using
the "JUMP" key.

Use the following procedure to change the language.

1. Press the "JUMP" key.

2. Use the Navigation Key for UP and the Navigation Key for DOWN In order to step to
channel 4231.
3. Press the "SEL" key.

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 4. Choose the password by using the Navigation Key for UP and the Navigation Key for
DOWN and press the "SEL" key.
5. Use the Navigation Key for UP and the Navigation Key for DOWN and select the desired
language.
6. Press the "SEL" key.

Note: The password must be re-entered when the display has not been used for 3 minutes.

Alarms :

The following steps describe the function of the alarm.

1. An alarm occurs. The alarm light starts flashing.

2. The display automatically shows the alarm information.
3. Move the cursor to "ACK" and press the "SEL" key in order to acknowledge the alarm. Take
the necessary action for the alarm.
4. The alarm will disappear when the condition that caused the alarm is no longer present.
5. Alarms that have not been acknowledged are still present if the alarm light flashes.
6. Use the navigation keys in order to step through the list of alarms.

Warnings :

"WARNING BATTERY VOLTAGE" - If the control module detects voltage from the alternator that
is below the setting for low voltage, the display will show "BATTERY LOW V". The alarm indicator
illuminates, and an audible alarm is activated.

"FAIL TO STOP" - If the control module determines that the signal from the engine speed sensor
indicates that the engine is running but the engine should not be running, the display will show
"STOP FAIL". The alarm indicator illuminates, and an audible alarm is activated.

"WARNING LOW OIL PRESSURE" - If the control module detects engine oil pressure that has
fallen below the setting for low oil pressure (warning), the display will show "LOW OIL PRESS".
The alarm indicator illuminates, and an audible alarm is activated. This warning is only active after
the engine has exceeded the Safety On Timer.

"WARNING HIGH COOLANT TEMP" - If the control module detects engine coolant temperature
that has exceeded the setting for high coolant temperature (warning), the display will show "HIGH
ENGINE TEMP". The alarm indicator illuminates, and an audible alarm is activated. This warning is
only active after the engine has exceeded the "Safety On" Timer.

"WARNING OVERSPEED" - If the engine speed exceeds the setting for engine overspeed
(warning), the display will show "OVERSPEED". The alarm indicator illuminates, and an audible
alarm is activated.

"WARNING GENERATOR HIGH FREQUENCY" - If the control module detects a output

frequency for the generator that exceeds the setting for high generator frequency (warning), the
display will show "Hz/V FAILURE". The alarm indicator illuminates, and an audible alarm is
activated.

"WARNING GENERATOR LOW FREQUENCY" - If the control module detects a output frequency
for the generator that is below the setting for low generator frequency (warning), the display will
show "Hz/V FAILURE". The alarm indicator illuminates, and an audible alarm is activated.

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"GENERATOR HIGH VOLTAGE WARNING" - If the control module detects a output voltage for
the generator that exceeds the setting for high generator voltage (warning), the display will show
"OVER VOLTAGE". The alarm indicator illuminates, and an audible alarm is activated.

"GENERATOR LOW VOLTAGE WARNING" - If the control module detects a output voltage for
the generator that is less than the setting for low generator voltage (warning), the display will show
"UNDER VOLTAGE". The alarm indicator illuminates, and an audible alarm is activated.

"LUB OIL HIGH TEMPERATURE ALARM" - If the control module detects a high lube oil
temperature in excess of 120 degrees celsius for four cylinder engines and in excess of 130
degrees celsius for six cylinder engines (warning), the display will show "LUB OIL HIGH". The
alarm indicator illuminates.

"SHUTDOWN OVERRIDE" - If the control module detects an override for engine shutdown and
the switch is set to OVERRIDE, the display will show "S/D OVERRIDE". The alarm indicator
illuminates, and an audible alarm is activated.

"STARTING AIR PRESSURE LOW ALARM OPTIONAL" - If the control module detects low
starting air pressure (warning), the display will show "START AIR P LOW". The alarm indicator
illuminates, and an audible alarm is activated.

"GENERATOR WINDING OR BEARING OVER TEMPERATURE ALARM OPTIONAL" - If the

control module detects a generator bearing over temperature (warning), the display will show
"GEN BRG OVER TEMP". The alarm indicator illuminates, and an audible alarm is activated.

"EXTERNAL FUEL TANK LEVEL ALARM OPTIONAL" - If the control module detects a
low fuel level in an external fuel tank, the display will show "EXT FUEL T LOW". The alarm
indicator illuminates, and an audible alarm is activated.

"HIGH EXHAUST TEMPERATURE ALARM OPTIONAL" - If the control module detects a high
exhaust temperature (warning), the display will show "HIGH EXH TEMP". The alarm indicator
illuminates, and an audible alarm is activated.

"HIGH PRESSURE FUEL LEAK ALARM OPTIONAL" - If the control module detects a high
pressure fuel leak (warning), the display will show "H P FUEL LEAK". The alarm indicator
illuminates, and an audible alarm is activated.

"WATER IN FUEL ALARM OPTIONAL" - If the control module detects a signal for water in fuel
(warning), the display will show "WATER IN FUEL". The alarm indicator illuminates, and an audible
alarm is activated.

Shutdowns :

"SHUTDOWN FAIL TO START" - If the engine does not start after a preset number of attempts,
the display will show "Hz/V FAILURE". The alarm indicator will flash, and an audible alarm is
activated.

"SHUTDOWN EMERGENCY STOP" - If the voltage signal at the input for the emergency stop is
disconnected, the display will show "E-STOP". The generator set will not start until the emergency
stop push button has been reset. Power is removed from the fuel solenoid and the starter solenoid.
The alarm indicator will flash, and an audible alarm is activated.

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"SHUTDOWN LOW OIL PRESSURE" - If the control module detects engine oil pressure that has
fallen below the setting for low oil pressure (shutdown), the display will show "LOW O P S/DOWN".
The alarm indicator will flash, and an audible alarm is activated. This warning is only active after
the engine has exceeded the Safety On Timer.

"SHUTDOWN HIGH COOLANT TEMPERATURE" - If the control module detects engine coolant
temperature that has exceeded the setting for high coolant temperature (shutdown), the display will
show "HET S/DOWN". The alarm indicator will flash, and an audible alarm is activated. This
warning is only active after the engine has exceeded the "Safety On" Timer.

"SHUTDOWN OVERSPEED" - If the engine speed exceeds the setting for engine overspeed
(shutdown), the display will show "Hz/V FAILURE". The alarm indicator will flash, and an audible
alarm is activated.

"SHUTDOWN UNDERSPEED" - If the engine speed falls below the setting for engine underspeed
(shutdown), the display will show "F/U FAIL". The alarm indicator will flash, and an audible alarm is
activated. This warning is only active after the engine has exceeded the "Safety On" Timer.

"SHUTDOWN GENERATOR HIGH FREQUENCY" - If the control module detects a output

frequency for the generator that exceeds the setting for high generator frequency (shutdown), the
display will show "Hz/V FAILURE". The alarm indicator will flash, and an audible alarm is activated.

"SHUTDOWN GENERATOR LOW FREQUENCY" - If the control module detects a output

frequency for the generator that is below the setting for low generator frequency (shutdown), the
display will show "Hz/V FAILURE". The alarm indicator will flash, and an audible alarm is activated.

"GENERATOR HIGH VOLTAGE SHUTDOWN" - If the control module detects a output voltage for
the generator that exceeds the setting for high generator voltage (shutdown), the display will show
"HIGH VOLT S/D". The alarm indicator will flash, and an audible alarm is activated.

"GENERATOR LOW VOLTAGE SHUTDOWN" - If the control module detects a output voltage for
the generator that is less than the setting for low generator voltage (shutdown), the display will
show "LOW VOLT S/D". The alarm indicator will flash, and an audible alarm is activated.

"ELECTRONIC GOVERNOR FAILURE SHUTDOWN" - If the control module detects an electronic

governor failure (shutdown), the display will show "GOV FAIL S/DOWN". The alarm indicator
illuminates, and an audible alarm is activated.

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Maintenance :
Schedule :

When Required :

Battery - Replace
Battery or Battery Cable - Disconnect
Engine - Clean
Fuel System - Prime
Fuel System - Prime
Generator - Dry
Generator Load - Check
Generator Set - Test
Rotating Rectifier - Check
Rotating Rectifier - Test
Sea Water Strainer - Clean/Inspect
Severe Service Application - Check

Daily :

Cooling System Coolant Level - Check

Electrical Connections - Check
Engine Air Cleaner Service Indicator - Inspect
Engine Oil Level - Check
Fuel System Primary Filter/Water Separator - Drain
Fuel Tank Water and Sediment - Drain
Generator - Inspect
Power Factor - Check
Walk-Around Inspection

Every Week :

Automatic Start/Stop - Inspect

Bearing Temperature - Measure/Record
Hoses and Clamps - Inspect/Replace
Instrument Panel - Inspect
Jacket Water Heater - Check
Standby Generator Set Maintenance Recommendations

Every 250 Service Hours :

Cooling System Coolant Sample (Level 1) - Obtain

Engine Oil Sample - Obtain

Initial 500 Service Hours :

Engine Valve Lash - Inspect/Adjust

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Every 500 Service Hours :

Belts - Inspect/Adjust/Replace
Engine Crankcase Breather - Replace
Engine Oil and Filter - Change
Fuel System Primary Filter (Water Separator) Element - Replace
Fuel System Secondary Filter - Replace

Every 500 Service Hours or 1 Year :

Auxiliary Water Pump - Inspect

Battery Electrolyte Level - Check
Cooling System Supplemental Coolant Additive (SCA) - Test/Add
Engine Air Cleaner Element - Clean/Replace
Radiator - Clean
Sea Water Strainer - Clean/Inspect

Every 1000 Service Hours :

Aftercooler Condensate Drain Valve - Inspect/Clean

Engine Valve Lash - Inspect/Adjust
Magnetic Pickups - Clean/Inspect
Water Pump - Inspect

Every 1000 Service Hours or 1 Year :

Battery Charger - Check

Every 2000 Service Hours :

Engine Mounts - Inspect

Heat Exchanger - Inspect
Insulation - Test
Starting Motor - Inspect
Turbocharger - Inspect

Every 2000 Service Hours or 1 Year :

Alternator - Inspect
Generator Set Vibration - Inspect

Every Year :

Cooling System Coolant Sample (Level 2) - Obtain

Every 3000 Service Hours or 2 Years :

Cooling System Coolant (DEAC) - Change

Cooling System Water Temperature Regulator - Replace

Every 3000 Service Hours or 3 Years :

Engine Protective Devices - Check

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Every 4000 Service Hours :

Aftercooler Core - Clean/Test

Every 6000 Service Hours or 3 Years :

Cooling System Coolant Extender (ELC) - Add

Every 12 000 Service Hours or 6 Years :

Cooling System Coolant (ELC) - Change

Overhaul :

Overhaul Considerations

Welding On Engines With Electronic Controls :

Proper welding procedures are necessary in order to avoid damage to the engine's ECM, sensors,
and associated components. When possible, remove the component from the unit and then weld
the component. If removal of the component is not possible, the following procedure must be
followed when you weld on a unit that is equipped with a Caterpillar Electronic Engine. The
following procedure is considered to be the safest procedure to weld on a component. This
procedure should provide a minimum risk of damage to electronic components.

Note : Do not ground the welder to electrical components such as the ECM or sensors. Improper
grounding can cause damage to the drive train, the bearings, hydraulic components, electrical
components, and other components.

Do not ground the welder across the centerline of the package. Improper grounding could cause
damage to the bearings, the crankshaft, the rotor shaft, and other components.

Clamp the ground cable from the welder to the component that will be welded. Place the clamp as
close as possible to the weld. This will help reduce the possibility of damage.

Perform the welding in areas that are free from explosive hazards.

1. Stop the engine. Turn the switched power to the OFF position.

2. Disconnect the negative battery cable from the battery. If a battery disconnect switch is
provided, open the switch.

3. Disconnect the J1/P1 and J2/P2 connectors from the ECM. Move the harness to a position
that will not allow the harness to accidentally move back and make contact with any of the
ECM pins.

4. Connect the welding ground cable directly to the part that will be welded. Place the ground
cable as close as possible to the weld in order to reduce the possibility of welding current
damage to bearings, hydraulic components, electrical components, and ground straps.

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 Note: If electrical/electronic components are used as a ground for the welder, or
electrical/electronic components are located between the welder ground and the weld,
current flow from the welder could severely damage the component.

(1) Engine
(2) Welding electrode
(3) Keyswitch in the OFF position
(4) Battery disconnect switch in the open
position
(5) Disconnected battery cables
(6) Battery
(7) Electrical/Electronic component
(8) Minimum distance between the
component that is being welded and any
electrical/electronic component
(9) The component that is being welded
(10) Current path of the welder
(11) Ground clamp for the welder

5. Protect the wiring harness from welding debris and spatter.

6. Use standard welding practices to weld the materials.

Finding Top Center Position for No. 1 Piston :

Required Tools

Tool Part Number Part Description Qty

A (1) 9U-6198 Crankshaft Turning Tool 1

9U-7336 Housing 1
A (2)
5P-7305 Engine Turning Tool 1

B 230-6284 Timing Pin (Camshaft) 1

136-4632 Timing Pin (Crankshaft) 1

C
268-1966 Adapter 1
(1)
The Crankshaft Turning Tool is used on the front pulley.
(2)
This Tool is used in the aperture for the electric starting motor.

1. Remove the front cover.

2. Use Tooling (A) in order to rotate the crankshaft until
the hole (X) in the camshaft gear (1) aligns with the
hole in the front housing.

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 3. Install Tooling (B) through the hole
(X) in the camshaft gear (1) into the
front housing. Use Tooling (B) in
order to lock the camshaft in the
correct position.

4. Remove the plug (4) from the cylinder block. Install Tooling (C) into the hole (Y) in the
cylinder block. Use Tooling (C) in order to lock the crankshaft in the correct position.

Note: Do not use excessive force to install Tooling (C) . Do not use Tooling (C) to hold the
crankshaft during repairs.

Engine Valve Lash - Inspect/Adjust :

Required Tools

Tool Part Number Part Description Qty

A 228-3610 Angled feeler gauge 1

(A) Inlet Valve

(B) Exhaust Valve

If the valve lash requires adjustment several times in a short period of time, excessive wear exists
in a different part of the engine. Find the problem and make necessary repairs in order to prevent
more damage to the engine.

Not enough valve lash can be the cause of rapid wear of the camshaft and valve lifters. Not
enough valve lash can indicate that the seats for the valves are worn.

Valves become worn due to the following causes:

 Fuel injection nozzles that operate incorrectly

 Excessive dirt and oil are present on the filters for the inlet air.
 Incorrect fuel settings on the fuel injection pump.
 The load capacity of the engine is frequently exceeded.

Too much valve lash can cause broken valve stems, springs, and spring retainers. Too much valve
lash can be an indication of the following problems:

 Worn camshaft and valve lifters

 Worn rocker arms
 Bent pushrods

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  Broken socket on the upper end of a pushrod
 Loose adjustment screw for the valve lash

If the camshaft and valve lifters show rapid wear, look for fuel in the lubrication oil or dirty
lubrication oil as a possible cause.

Valve Lash Check :

An adjustment is NOT NECESSARY if the measurement of the valve lash is in the acceptable
range. Check the valve lash while the engine is stopped. The temperature of the engine does not
change the valve lash setting.

Valve Lash Adjustment :

Inlet Valves Exhaust Valves

Valve Lash 0.35 mm (0.0138 inch) 0.35 mm (0.0138 inch)

TC Compression Stroke 1-2-4 1-3-5

TC Exhaust Stroke (1) 3-5-6 2-4-6

Firing Order 1-5-3-6-2-4 (2)

(1)
360° from TC compression stroke
(2)
The No. 1 Cylinder is at the front of the engine.

(A) Angled feeler gauge

(1) Adjustment screw
(2) Locking screw
1

2
A

Warning : Accidental engine starting can cause injury or death to personnel. To prevent accidental
engine starting, turn the ignition switch to the OFF position and place a do not operate tag at the
ignition switch location.

1. Remove the valve mechanism cover.

2. Rotate the crankshaft in the direction of engine rotation until the inlet valve of the No. 6
cylinder has opened and the exhaust valve of the No. 6 cylinder has not completely closed.
The engine is now at TC compression stroke.

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 TC Compression Stroke Inlet Valves Exhaust Valves

Valve Lash 0.35 mm (0.0138 inch) 0.35 mm (0.0138 inch)

Cylinders 1-2-4 1-3-5

3. Measure the valve lash for the valve when the engine is at TC compression stroke
according to table. If necessary, make an adjustment to the valves according to table.

a. Loosen the valve adjustment screw locknut that is on the adjustment screw (1) .

b. Place Tooling (A) between the rocker arm and the valve. Turn the adjustment screw
(1) while the valve adjustment screw locknut (2) is being held from turning. Adjust
the valve lash until the correct specification is achieved.

c. After each adjustment, tighten the valve adjustment screw locknut (2) while you hold
the valve adjustment screw (1) from turning.

4. Rotate the crankshaft in the direction of engine rotation to TC exhaust stroke (360° from TC
compression stroke).

TC Exhaust Stroke (1) Inlet Valves Exhaust Valves

Valve Lash 0.35 mm (0.0138 inch) 0.35 mm (0.0138 inch)

Cylinders 3-5-6 2-4-6

(1)
360° from TC compression stroke

5. Measure the valve lash for the valves when the engine is at TC exhaust stroke according to
table. If necessary, make an adjustment to the valves according to table.

a. Loosen the valve adjustment screw locknut that is on the adjustment screw (1) .

b. Place an appropriate feeler gauge (2) between the rocker arm and the valve. Turn
the adjustment screw (1) while the valve adjustment screw locknut is being held
from turning. Adjust the valve lash until the correct specification is achieved.

c. After each adjustment, tighten the valve adjustment screw locknut while you hold
the valve adjustment screw (1) from turning.

6. Install the valve mechanism cover.

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Fuel Injection Timing – Check :

Required Tools

Tool Part Number Part Description Qty

A 338-1054 Fuel Injection Pump Timing Tool 1

This procedure must be done before any of the following reasons:

 Removal of the fuel injection pump

 The bolts that hold the fuel injection pump to the front housing are loosened.

1. Set the number one piston at the top center piston on the compression stroke.

2. Carefully remove the fuel injection pump from the front housing.

3. To check the fuel injection pump timing, follow Steps 3.a and 3.b.

a. Position Tooling (A) onto the shaft (8) of the fuel injection pump. Align the lever of
Tooling (A) with the key slot (7) . Engage the lever into the key slot.

b. Insert the locking pin of Tooling (A) into the hole (6) in fuel injection pump.
If the locking pin can be inserted into the hole, the fuel injection pump timing is
correct.

If the locking pin cannot be inserted into the hole, the fuel injection pump timing is
not correct.

Note: There should be no resistance when the locking pin is inserted.

4. If the fuel injection pump timing has been lost follow Steps 4.a through 4.e in order to reset
the fuel injection pump timing.

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 a. If necessary, loosen the locking screw (4) on the fuel injection pump. Slide the
spacer (5) into position (X) . Tighten the locking screw (4) to a torque of 9 N·m (80
lb in). This will prevent the locking screw from tightening against the shaft (8) .

The fuel injection pump is now unlocked.

b. Position Tooling (A) onto the shaft (8) of the fuel injection pump. Align the lever of
Tooling (A) with the key slot (7) in the fuel injection pump. Engage the lever into the
key slot.

c. Use the lever of Tooling (A) to rotate the shaft (8) until the pin of Tooling (A) can be
engaged into the hole (6) . Engage the pin of Tooling (A) into the hole.

d. Loosen the locking screw (4) in the fuel injection pump. Slide the spacer (5) into
position (Y) . Tighten the locking screw (4) against the shaft of the fuel injection
pump to a torque of 9 N·m (80 lb in).

The fuel injection pump is now locked.

e. Remove Tooling (A) .

5. Reinstall the fuel injection pump to the front housing.

Injector Trim File :

The electronic service tool is used to load the injector trim files into the Electronic Control Module
(ECM).

The injector trim files must be loaded into the ECM if any of the following conditions occur:

 An electronic unit injector is replaced.

 The ECM is replaced.
 Diagnostic code 268-2 is active.
 Electronic unit injectors are exchanged between cylinders.

Exchanging Electronic Unit Injectors :

Exchanging electronic unit injectors can help determine if a combustion problem is in the electronic
unit injector or in the cylinder. If two electronic unit injectors that are currently installed in the
engine are exchanged between cylinders, the injector trim files can also be exchanged. Press the
"Exchange" button at the bottom of the "Injector Trim Calibration" screen on the electronic service
tool. Select the two electronic unit injectors that will be exchanged and press the "OK" button. The
tattletale for the electronic unit injectors that were exchanged will increase by one.

Note: The serial number for the electronic unit injector and the
confirmation code number for the electronic unit injector are located
on the electronic unit injector.

1. Record the serial number and the confirmation code

numberfor each electronic unit injector.

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2. Obtain the injector trim file by one of the following methods:
o Select "Service Software Files" on SIS.
o Use the compact disc that is included with a replacement electronic unit injector.

3. Enter the serial number for the electronic unit injector in the search field.

4. Download the injector trim file to the PC. Repeat this procedure for each electronic unit
injector, as required.

5. Connect the electronic service tool to the diagnostic connector.

6. Turn the keyswitch to the ON position.

7. Select the following menu options on the electronic service tool:

o Service
o Calibrations
o Injector Trim Calibration

8. Select the appropriate cylinder.

9. Click on the "Change" button.

10. Select the appropriate injector trim file from the PC.

11. Click on the "Open" button.

12. If a prompt is displayed on the electronic service tool, enter the confirmation code number
for the electronic unit injector into the field.

13. Click on the "OK" button.

The injector trim file is loaded into the ECM.

14. Repeat the procedure for each cylinder, as required.

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Troubleshooting :
Diagnostic Codes :

The Electronic Control Module (ECM) has the ability to detect problems with the electronic system
and with engine operation. When a problem is detected, a code is generated. An alarm may also
be generated. There are two types of codes:

 Diagnostic
 Event

Diagnostic Code : When a problem with the electronic system is detected, the ECM generates a
diagnostic code. This indicates the specific problem with the circuitry.

Diagnostic codes can have two different states:

 Active
 Logged

Active Code : An active diagnostic code indicates that an active problem has been detected.
Active codes require immediate attention. Always service active codes prior to servicing logged
codes.

Logged Code : Every generated code is stored in the permanent memory of the ECM. The codes
are logged.

Logged codes may not indicate that a repair is needed. The problem may have been temporary.
The problem may have been resolved since the logging of the code. If the system is powered, it is
possible to generate an active diagnostic code whenever a component is disconnected. When the
component is reconnected, the code is no longer active. Logged codes may be useful to help
troubleshoot intermittent problems. Logged codes can also be used to review the performance of
the engine and of the electronic system.

Event Code : The Electronic Control Module (ECM) monitors engine operating conditions such as
low oil pressure or high coolant temperature. If an operating condition exceeds the normal
condition, an event code is generated. The event code will be active until the condition returns to
normal. The ECM also logs the event. Events usually indicate a mechanical problem instead of an
electronic system problem.

Events can be in the form of a warning, a derate or a shutdown.

Flash Codes :

The "Flash Code" feature is used to flash the two digit code of all active diagnostic and event
codes.

When a diagnostic code or an event code is active or logged, the diagnostic lamp will flash
repeatedly in order to indicate the codes.

Each flash will be on for half a second and off for 300 milliseconds. The "Diagnostic" lamp will
remain off for two seconds between each digit of a code. If there is more than one diagnostic code,
the "Diagnostic" lamp will go off for five seconds. The lamp will then flash in order to indicate the
next code.

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As an example, an active diagnostic code of "21" is indicated by the "Diagnostic" lamp coming on
for 500 ms, then off for 300 ms, then on for 500 ms, then off for 2000 ms, then on for 500 ms and
then off.

Once all codes have been flashed, the "Diagnostic" lamp will go off for a period of 15 seconds
before starting the sequence again.

Note : Flash codes are always sent in ascending numerical order.

CAT ET 3rd Party

Flash
CDL Code Description J1939 Device J1939
Code
Code Code

0001-02 Cylinder #1 Injector Data Incorrect J651-2 651-2 71

0001-05 Cylinder #1 Injector open circuit J651-5 651-5 71

0001-06 Cylinder #1 Injector short J651-6 651-6 71

0001-07 Cylinder #1 Injector Not Responding J651-7 651-7 71

0002-02 Cylinder #2 Injector Data Incorrect J652-2 652-2 72

0002-05 Cylinder #2 Injector open circuit J652-5 652-5 72

0002-06 Cylinder #2 Injector short J652-6 652-6 72

0002-07 Cylinder #2 Injector Not Responding J652-7 652-27 72

0003-02 Cylinder #3 Injector Data Incorrect J653-2 653-2 73

0003-05 Cylinder #3 Injector open circuit J653-5 653-5 73

0003-06 Cylinder #3 Injector short J653-6 653-6 73

0003-07 Cylinder #3 Injector Not Responding J653-7 653-7 73

0004-02 Cylinder #4 Injector Data Incorrect J654-2 654-2 74

0004-05 Cylinder #4 Injector open circuit J654-5 654-5 74

0004-06 Cylinder #4 Injector short J654-6 654-6 74

0004-07 Cylinder #4 Injector Not Responding J654-7 654-7 74

0005-02 Cylinder #5 Injector Data Incorrect J655-2 655-2 75

0005-05 Cylinder #5 Injector open circuit J655-5 655-5 75

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0005-06 Cylinder #5 Injector short J655-6 655-6 75

0005-07 Cylinder #5 Injector Not Responding J655-7 655-7 75

0006-02 Cylinder #6 Injector Data Incorrect J656-2 656-2 76

0006-05 Cylinder #6 Injector open circuit J656-5 656-5 76

0006-06 Cylinder #6 Injector short J656-6 656-6 76

0006-07 Cylinder #6 Injector Not Responding J656-7 656-7 76

0041-03 8 Volt DC Supply short to +batt J678-03 678-03 21

0041-04 8 Volt DC Supply short to ground J678-04 678-04 21

0091-08 Throttle Position signal abnormal J91-08 91-08 32

0100-03 Engine Oil Pressure open/short to +batt J100-03 100-03 24

0100-04 Engine Oil Pressure short to ground J100-04 100-04 24

Engine Oil Pressure Sensor abmormal rate of

0100-10 J100-10 100-10 26
change

0110-03 Engine Coolant Temperature open/short to +batt J110-03 110-03 27

0110-04 Engine Coolant Temperature short to ground J110-04 110-04 27

0168-00 System Voltage High J168-00 168-00 51

0168-01 System Voltage Low J168-01 168-01 51

0168-02 System Voltage intermittent/erratic J168-02 168-02 51

0172-03 Intake Manifold Air Temp open/short to +batt J105-03 105-03 38

0172-04 Intake Manifold Air Temp short to ground J105-04 105-04 38

0190-08 Engine Speed signal abnormal J190-08 190-08 34

0247-09 J1939 Data Link communications J639-09 639-09 65

0253-02 Personality Module mismatch J631-02 631-02 56

0261-11 Engine Timing Calibration invalid J637-11 637-11 42

0262-03 5 Volt Sensor DC Power Supply short to +batt J1079-03 1079-03 21

0262-04 5 Volt Sensor DC Power Supply short to ground J1079-04 1079-04 21

0268-02 Check Programmable Parameters J630-02 630-02 56

0342-08 Secondary Engine Speed signal abnormal J723-08 723-08 34

1690-08 Analog Speed Demand Abnormal signal J29-08 29-08 66

1779-05 Fuel Rail Pressure Valve 1 Solenoid open circuit J1347-05 1347-05 47

Fuel Rail Pressure Valve 1 Solenoid short to ground

1779-06 J1347-06 1347-06 47

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 Fuel Rail Pressure Valve 1 Solenoid abnormal
1779-08 J1347-08 1347-08 47
frequency, pulse width or period

1785-03 Intake Manifold Pressure Sensor voltage high J102-03 102-03 25

1785-04 Intake Manifold Pressure Sensor voltage low J102-04 102-04 25

Intake Manifold Pressure Sensor abnormal rate of

1785-10 J102-04 102-04 25
change

1797-03 Fuel Rail Pressure Sensor open/short to +batt J157-03 157-03 37

1797-04 Fuel Rail Pressure Sensor short to ground J157-04 157-04 37

1834-02 Ignition Keyswitch loss of signal J158-02 158-02 -

Event Codes

E085-1 Shutdown Overriden J1237-1 1237-1 12

E255-1 Diagnostic Reset J704-00 704-00 59

E264-3 E-Stop Shutdown J970-31 970-31 58

E360-1 Low Oil Pressure - Warning J100-17 100-17 24

E360-3 Low Oil Pressure - Shutdown J100-01 100-01 24

E361-1 High Engine Coolant Temperature - Warning J110-15 110-15 27

E361-2 High Engine Coolant Temperature - Derate J110-16 110-16 27

E361-3 High Engine Coolant Temperature - Shutdown J110-00 110-00 27

E362-1 Engine Overspeed - Warning J190-15 190-15 35

E362-3 Engine Overspeed - Sutdown J190-00 190-00 35

E396-2 High Fuel Rail Pressure J157-15 157-15 47

E398-2 Low Fuel Rail Pressure J157-17 157-17 47

E539-1 High Intake Manifold Air Temperature - Warning J1636-15 1636-15 38

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Problem : Coolant in Engine Oil

Probable Causes :

 Engine oil cooler

 Cylinder head gasket
 Cylinder head
 Cylinder block

Problem : Coolant Temperature Is Too High

Probable Causes :

 Aftercooler
 Coolant level
 Radiator cap and/or pressure relief valve
 Coolant temperature gauge
 Restriction in the coolant system
 Water temperature regulator
 Coolant pump
 Auxiliary water pump
 Cylinder head gasket

Problem : Engine Cranks but Will Not Start

Probable Causes :

 Machine faults
 Diagnostic codes
 Visible faults
 Air intake and exhaust system
 Primary speed/timing sensor
 Low pressure fuel system
 Secondary speed/timing sensor
 High pressure fuel system
 Glow plugs
 Valve lash
 Low compression (cylinder pressure)

Problem : Engine Misfires, Runs Rough or Is Unstable

Probable Causes :

 Diagnostic codes
 Speed demand input
 Air intake and exhaust system
 Glow plugs
 Valve lash
 Fuel supply
 Fuel rail pump
 Low compression (cylinder pressure)
 Individual malfunctioning cylinder
 Electronic unit injectors

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Problem : Engine Oil in Cooling System

Probable Causes :

 Engine oil cooler

 Cylinder head gasket
 Cylinder head
 Cylinder block

Problem : Engine Vibration

Probable Causes :

 Vibration damper
 Engine supports
 Power generator
 Low compression (cylinder pressure)
 Individual malfunctioning cylinder
 Electronic unit injectors

Problem : Engine Will Not Crank

Probable Causes :

 Power generator
 Battery cables and/or batteries
 Starting motor solenoid or starting circuit
 Starting motor and/or flywheel ring gear
 Electrical power supply
 Internal engine fault
 Control system

Problem : Excessive Black Smoke

Probable Causes :

 Diagnostic codes
 ECM software
 Air intake system or exhaust system
 Valve lash
 Turbocharger
 Low compression (cylinder pressure)
 Individual malfunctioning cylinder
 Electronic unit injectors

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Problem : Excessive Engine Oil Consumption

Probable Causes :

 Misreading oil level

 Oil leaks
 Engine crankcase breather
 Oil level
 Air intake and exhaust system
 Turbocharger
 Low compression (cylinder pressure)

Problem : Excessive Fuel Consumption

Probable Causes :

 Fuel quality
 Quality of oil
 Low engine temperature
 Air intake and exhaust system
 Reduced pressure of intake air
 Excessive valve lash
 Failure of the primary speed/timing sensor

Problem : Excessive White Smoke

Probable Causes :

 Coolant temperature sensor circuit

 Low coolant temperature
 Glow plugs
 Fuel quality
 Valve lash
 Low compression (cylinder pressure)
 Individual malfunctioning cylinder

Problem : Low Engine Oil Pressure

Probable Causes :

 Engine oil level

 Oil specification
 Engine oil pressure gauge
 Engine oil filter
 Engine oil cooler
 Piston cooling jets
 Engine oil suction tube
 Engine oil pump
 Bearing clearance

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Problem : Low Power

Probable Causes :

 Diagnostic codes
 ECM parameters
 Electrical connectors
 Air intake and exhaust system
 Valve lash
 Turbocharger
 Fuel supply
 Low compression (cylinder pressure)
 Individual malfunctioning cylinder
 Electronic unit injectors

Caterpillar Electronic Technician (Cat ET) :

Cat ET can be used to diagnose problems with the C6.6 engine. The following tasks can be
performed with Cat ET to aid in engine diagnosis:

- View engine derates

- View component status
- Configure engine parameters
- View diagnostic codes and events
- Flash ECM
- Perform diagnostic tests

Before performing the above tasks, ensure the engine cranking speed is greater than 150 rpm and
the fuel rail pressure (while cranking engine) is greater than 17235 kPa (2500 psi).

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This screen displays all the warning, derate, and shutdown levels that are currently set within the
ECM.

The derates cannot be changed, but the derate information can be useful for diagnosing engine
faults.

A warning represents a serious problem with engine operation, but a warning condition does not
require a derate or a shutdown.

When an engine derate parameter is reached, the Engine ECM decreases the engine’s power to
help prevent possible engine damage.

When an engine shutdown parameter is reached, the Engine ECM shuts down the engine to help
prevent possible engine damage. When the Engine is derated by the Engine ECM, the ECM will
decrease engine power by reducing fuel and limiting engine speed. The engine is derated
according to the derate map in the specific machine application.

Note : The engine derate information shown in this illustration is not always available and is
dependent on the particular flash file.

This illustration shows a Cat ET status screen on the C6.6 engine. The status screens can be used
to view the component parameters to help detect engine problems.

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Cat ET configuration screens are used to configure engine parameters. This configuration screen
shows the Engine/Gear parameters, the Maintenance Parameters, and the Input/Output
Configuration Parameters.

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Diagnostic codes and events can be viewed and cleared with Cat ET. This illustration shows no
active diagnostic codes on the C6.6 engine.

This illustration shows the diagnostic tests that can be performed with Cat ET. The diagnostic tests
are:

Injector Solenoid Test - --The Injector Solenoid Test verifies that the circuits from the ECM to
the injector are functioning properly. The ECM injector power supply, the wiring harnesses, and
the injector solenoids are tested.

Override Parameters - --The Override Parameters function enables circuits, such as the check
engine lamp, to be turned on or off for troubleshooting purposes.

Cylinder Cutout Test - --The Cylinder Cutout Test allows selected cylinders to be disabled
(“cutout”) to help determine if a cylinder is misfiring.

Wiggle Test - --The Wiggle Test function allows the user to determine if there is an intermittent
wiring problem by indicating which parameter on the screen has moved beyond a predetermined
range while “wiggling” the wiring harness, sensors, connector, etc.

Fuel Rail Pump Solenoid Test - --The Fuel Rail Pump Solenoid Test verifies that the circuits
from the ECM to the pump solenoid are functioning properly. The ECM pump solenoid power
supply, the wiring harnesses, and the pump solenoid are tested.

Fuel System Verification Test - -The Fuel System Verification Test performs corrections, if
needed, to the current “start of injection time.” The verification test ensures all injectors are
trimmed correctly, running efficiently, and maintaining emissions output from the engine.

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Generator :

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Generator Connections :

The generator connections are located in the electrical box that is mounted on top of the generator.
Change the position of the wire terminals to modify the connection. The code for the winding is
specified on the nameplate. This illustration shows two typical terminal connection diagrams.

In any generator set installation, the frame of the generator must be positively connected to an
earth ground or to the hull of a vessel. The ground connection is the first connection that is made at
the installation and the last connection that should be removed. If the generator set is on flexible
mounting pads, the ground connection must be flexible to avoid possible breakage.

Ground connection cable or straps should have at least the current carrying capacity of the largest
line lead to the connected load. Joints in cables or straps must be clean, free of electrical
resistance, and protected from possible oxidation. Bolted ground connection joints eventually
oxidize. The joints are frequent sources of radio frequency interference (RFI). Joints that are silver
soldered and bolted are preferred.

Generators with a Wye Configuration usually have the neutral ground when the generator is
installed to prevent equipment damage. If the neutral wire is grounded and one of the phase leads
becomes grounded, the excessive current will open a load circuit breaker. Also, depending on the
following factors, the excessive current will cause the generator voltage to collapse: electrical
characteristics of the generator, type of fault, and trip rating of the circuit breaker. An undervoltage
device may be required to provide an adequate short circuit protection.

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There are some cases when the neutral wire is not grounded. An ungrounded generator neutral
lead is acceptable when the possibility of grounds to the phase leads has been eliminated, such as
ground fault protective circuits. Ground fault protection requires the entire group of distribution
circuits to be treated as a system. The owner should contact a certified consultant if a new
distribution system is being developed. The owner should also contact a certified consultant if an
existing system should be modified for the ground fault protection.

Each unit should be connected to a common ground. In a three-phase, four-wire system, the
neutral wire should be grounded according to local wiring codes.

Voltage Regulator :

The voltage regulator contains a F1 fuse (1) on the input power circuit for protection. The power
input terminals (2) and voltage sensing terminals (3) are located on the side of the voltage
regulator.

Generator voltage adjustments and configurations can be changed using the potentiometers and
straps located on the voltage regulator. The potentiometers and straps are:

P1 : Quad droop potentiometer (4)

P2 : Voltage potentiometer (5)
P3 : Stability potentiometer (6)
P5 : Excitation ceiling potentiometer (7)
ST1 : Single-phase detection strap (8)
ST2 : Response time (normal/fast) strap (9)
ST3 : Frequency strap (10)

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ST4 : External potentiometer strap (11)
ST5 : Load Acceptance Module (LAM) activation strap (12)
ST6 : Generator model selection strap (13)
ST9 : AREP/PGM selection strap (14)
ST10 : LAM 15% or 25% strap (15)
ST11 : Knee point 65 Hz (16)

AC DC

PMG

AC DC

AREP

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For generators with Auxiliary Winding Regulation Excitation Principle (AREP), the voltage regulator
is powered by two auxiliary windings. These windings are independent from the voltage sensing
circuit. The first winding is labelled as "X1" and "X2". This winding has a voltage that is proportional
with the output voltage of the generator. The second winding is labelled as "Z1" and "Z2". This
winding has a voltage that is proportional to the current of the stator. The voltage from the power
supply is rectified and filtered before being used by the AVR monitoring transistor. The generator
has a capacity of 3 IN for 10 seconds for a short circuit current. The generator also has good
immunity to distortion from the generator load.

For generators with PMG excitation, a permanent magnet generator is added to the generator at
the rear of the generator. The PMG supplies the voltage regulator with a voltage that is
independent of the main generator winding. The generator has a capacity of 3 IN for 10 seconds
for a short circuit current. The generator also has good immunity to distortion from the generator
load.

The voltage regulator monitors the output voltage of the generator. The voltage regulator corrects
the output voltage by adjusting the excitation current.

Sustained short circuit capacity (AREP and

3 IN for 10 seconds
PMG)

Standard power supply (AREP) Two auxiliary windings

Supply for shunt max 140 VAC at 50/60 Hz

Rated overload current 10 amperes for 10 seconds

Excitation ceiling current for 10 seconds and return to

Electronic protection for overload and loss approximately 1 ampere
of voltage sensing THE GENERATOR MUST BE STOPPED IN ORDER TO
RESET THE PROTECTION.

Fuse "F1" on input side "X1" and "X2"

Voltage sensing 5 VA that is isolated by the transformer

0-110V terminals 95 to 140 V

0-220V terminals 170 to 260 V

0-380V terminals 340 to 520 V

Voltage regulation ±0.5%

Rapid response time or normal response time from the location of jumper wire (ST2)

Voltage adjustment via potentiometer (P2)

Quadrature droop adjustment via potentiometer (P1)

Underspeed protection and adjustment of the frequency threshold via potentiometer (P4) (Factory setting)

Maximum adjustment for excitation via potentiometer (P5) (4 to 10 amperes)

(1)
50 or 60 Hz selection with jumper wire (ST3) .
(1)
The engine speed setting must be changed in order to change the frequency of the generator set.

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These voltage regulators may have an optional remote potentiometer for voltage adjustment. This
potentiometer is 470 ohms 3 W minimum. The adjustment range is 5%. The voltage range is
limited by the internal potentiometer "P2". Remove jumper wire "ST4" in order to connect the
potentiometer. A 1000 ohm potentiometer can also be used to extend the adjustment range.

AREP

PMG
The LAM system is integrated in the regulator and activated with the ST5 strap (1) on the voltage
regulator. The LAM system can be deactivated by removing the ST5 strap. The LAM can be
adjusted to 13% or 25% with the ST10 strap (2). The factory setting is 15%. When a load is applied
to the generator set, the rotation speed decreases. When the generator set speed decreases
below the preset frequency threshold, the LAM causes the voltage to decrease by approximately
13% or 25%. The amount of active load applied is reduced by approximately 25% to 45% until the
speed reaches the rated value again.

The LAM can be used to decrease the generator set speed variation (frequency) and its duration
for a given applied load, or to increase the applied load possible for one
speed variation, such as turbo-charged engines. To avoid voltage oscillations, the trip threshold for
the LAM function should be set approximately 2 Hz below the lowest frequency in steady state.
The LAM should be used at 25% for load impacts greater than or equal to 70% of the generator set
rated power.

Note : The LAM should not be used when paralleling generator sets.

Adjustments for Stand-alone Generators :

1. Remove jumper wire "ST4" and turn the remote adjustment potentiometer to the center
position.
2. Connect an analog voltmeter that is calibrated for 100 VDC on terminal "E+" and terminal
"E-".

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 3. Connect a voltmeter that is calibrated for 300 VAC to 500 VAC or 1000 VAC to the output
terminals of the generator.
4. Make sure that the "ST3" jumper wire is positioned on the desired frequency.
5. Turn potentiometer "P2" to a full counterclockwise position.
6. Turn the potentiometer "P4" to a full clockwise position.
7. Turn stability potentiometer "P3" counterclockwise to about 1/3 of the total rotation for the
potentiometer.
8. Start the engine and set the engine speed to a frequency of 48 Hz for 50 Hz or 58 Hz for 60
Hz.
9. Adjust the output voltage to the correct value with potentiometer "P2". This voltage should
be the rated voltage UN for single operation or UN plus 2% to 4% for parallel operation with
a current transformer. Adjust potentiometer "P3" in both directions while you observe the
voltage between "E+" and "E-". The voltage between "E+" and "E-" should be
approximately 10 VDC. The best response times are obtained at the limit of the instability.
Try cutting or replacing the jumper wire "ST2" if no stable position can be obtained.
10. Check the operation of the Load Adjustment Module (LAM). "ST5" must be jumpered. The
LAM can be adjusted to 15% or 25% voltage dip by moving the "ST10" jumper wire.
11. Turn potentiometer "P4" slowly counterclockwise until there is a significant voltage drop.
The voltage drop should be approximately 15%.
12. Vary the frequency around 48 Hz or 58 Hz according to the operating frequency. Check the
change in the voltage that was previously observed.
13. Readjust the speed of the unit to the rated no-load value.

Adjustments for Generators in Parallel Operation :

Note : Make sure that the speed droop is identical for all of the engines before adjustments are
made to the generator.

1. Preset the unit for parallel operation by connecting the current transformer to "S1" and "S2"
of the connector "J2". Set quadrature droop potentiometer "P1" to the center position. Apply
the rated load. The voltage should drop by 2% to 3%. Switch the positions of the two
incoming secondary wires of the current transformer if the voltage increases.
2. The no-load voltages should be identical for all the generators that are intended to be run in
parallel. Connect the generators in parallel. Try to obtain a 0 kW power exchange by
adjusting the speed of the generator. Try to minimize the circulating currents between
generators by altering the voltage setting with potentiometer "P2" or "Rhe" on one of the
generators.

Note : Do not change the voltage settings after this step.

3. Apply the available load. The setting is correct only if a reactive load is available. Equalize
the kilowatts or divide the rated power of the units proportionally by altering the speed. Alter
the quadrature droop potentiometer "P1" in order to equalize the currents or divide the
currents.

Adjustment for Max. Excitation :

The maximum factory setting corresponds to an

excitation current that is required to obtain a three-
phase short circuit current of 3 IN at 50 Hz for industrial
power, unless specified otherwise.

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The maximum level of excitation may be reduced by a static method. The static method is safer for
the generator and the installation. Use the following steps to reduce the maximum excitation level.

1. Disconnect the power supply wires "X1", "X2", "Z1" and "Z2".
2. Disconnect sensing leads 0V, 110V, 220V and 380V on the generator.
3. Connect the main power supply 200V-240V to "X1" and "X2", as shown.
4. Install a 10 Amp DC ammeter in series with the exciter field.
5. Turn potentiometer "P5" to a full counterclockwise position and activate the power supply. If
there is no output current from the voltage regulator, turn potentiometer "P2" clockwise until
the ammeter indicates a stable current.
6. Switch off the power supply. Switch on the power supply. Turn potentiometer "P5" until the
required maximum current is obtained. The maximum current must not be greater than 10
Amperes.

Use the following steps in order to check the internal protection.

1. Open switch "D". The excitation current should increase up to the preset maximum value
and the excitation current should remain at the preset maximum value for approximately 10
seconds. The current will decrease to less than 1 Amp.
2. Open switch "A" in order to reset the internal protection.
Note : The voltage must be adjusted after the maximum excitation current has been set.

Special Use :

The exciter is switched off by disconnecting the power

supply to the voltage regulator. The connection is identical
for resetting the internal protection for the voltage regulator.

Use a 12 VDC power source in order to

energize the field, if necessary. Refer to the
following table.

Applications B Volts Time

Voltage build up 12 (1A) 1 - 2 seconds

De-energized parallel operation 12 (1A) 1 - 2 seconds

Standstill parallel operation 24 (2A) 5 - 10 seconds

Frequency starting 48 (4A) 5 - 10 seconds

Voltage that is sustained at overload 48 (4A) 5 - 10 seconds

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Generator Maintenance :

When Required :

• Generator - Dry, Load Check, Test

• Rotating rectifier - Check, Test

Daily :

• Generator - Inspect
• Power Factor - Check
• Walk-Around Inspection

Every Week :

• Automatic Start/Stop - Inspect

• Bearing Temperature - Measure/Record
• Instrument Panel - Inspect

Every 1000 Service Hours :

• Magnetic Pickups - Clean/Inspect

Every 2000 Service Hours :

• Insulation - Test

Every 2000 Service Hours or One Year :

• Generator Set Vibration - Inspect

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