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General Information
with Mechanically Actuated Injector

Note : Warranty repairs must be performed at a Cummins® Authorized Repair

Location to accurately calibrate, test, and repair the fuel systems on Cummins®
engines.
When removing the injectors from the engine, compare the injector assembly part number with
the appropriate Control Parts List (CPL) assembly part number listed in the CPL manual, Bulletin
3379133.
Note : The injector plunger and the barrel are machined to a very precise tolerance
and are available as a match-fit assembly only. Do not mix the plungers and the
barrels. Always replace the plunger and the barrel as a matched assembly if the
injector is rebuilt.
Note : The outer base circle (OBC) valve and injector setting procedure can be used
for all fixed time PT™ and hydraulic variable timing/STC engines, regardless of CPL or
build date.
Note : All STC injector locknuts are made of powdered metal. These locknuts are
porous by nature. When air pressure is applied to the STC oil delivery system, it is
normal to see air bubbles form on the locknut. This is acceptable leakage. However,
an audible air leak from a crack or hole in the locknut is unacceptable.
The injector barrel, plunger assembly, and injector cup are the parts most commonly replaced
when rebuilding an injector.
The barrel, plunger assembly, and plunger to cup seal must pass an injector leakage test. See
the Injector PT™ Rebuild Manual, Bulletin 3379071.
The injector stop screw was designed for standardization purposes. The stop screw is used to
adjust the top-stop setting of the injector, and also acts as a housing for the tappet assembly. The
revised injector stop screw can be used in all previous STC injector assemblies.
KT injector cups were released for the KTA marine injector in September, 1987 (Engine Serial
Number first 33112795).
Due to injector plunger wear, a more durable D4 material replaced the 4140 material on the 9.5
mm [0.37 in] plunger in November, 1987 (Engine Serial Number first 33113265).
The following injectors have been fitted to K38 and K50 engines. Although this is not a complete
list, it does cover the basic injector configurations which have been used.

The Standard K (non-top-stop) injector was the first injector fitted to the KV Series engine.

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Reduced Drain Flow injectors were released as follows:

Engine Engine Serial Number Release Date

KTTA50-C 33111642 November 15, 1986
KT50-C 33111665 November 15, 1986
KTA50-C 33111645 November 15, 1986
KTA50-G 33111204 November 15, 1986
KTTA38-G 33111291 November 15, 1986
The injectors contained the same parts as previous injectors, except for the barrel and plunger
assembly.
The injector drain flow is decreased by reducing the drain passage in the reduced drain flow
barrel. The lower drain flow reduces the total flow required. The reduction in flow allows the use
of the PT™ (Type G) pump in place of the PT™ (Type H) pump. It also allows the use of a 19 mm
[0.75 in] PT™ (Type G) gear pump on K38 engines that previously used the 32 mm [1.25 in]
PT™ (Type G) gear pump.

 CAUTION 
Reduced drain flow injectors must be used in complete sets due to the differences in total
flow between the previous standard and reduced drain flow injectors. Failure to do so can
result in engine damage.

Reduced drain flow injector assemblies were released for STC and non-STC injector
configurations.

A full top-stop injector was released for K series engines in July, 1987 (Engine Serial Number first
33112560). This injector replaced the K hydraulic variable timing/STC injector. The full top-stop
injector performs the same function as the previous K hydraulic variable timing/STC injectors,
advancing the injection timing by trapping engine oil in the injector's hydraulic tappet. However,
the revised injector has an additional top-stop feature to help reduce overhead wear. A top cap is
used to stop the upward movement of the STC tappet. This unloads the injector train briefly,
allowing oil to lubricate the link and socket joints.
Several of the components of the previous K hydraulic variable timing/STC injector were
redesigned in order to convert to the full top-stop design, and some additional components were
added.
The revised K full top-stop STC injector required a different oil transfer tube. The older tube was
7.93 mm [0.3125 in] longer, and will not fit into the oil feed locknut of the revised injector.

The K family STC injector was released for service and production on single stage uprate
engines in February, 1988 (Engine Serial Number first 33113700).

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These injectors are a similar style to the full top-stop STC injector. However, there are several
differences.
Injector Adapter - The adapter has two major features which make it different from the K STC
injector adapter. First, the adapter was modified so that the same o-ring can be used at all
three o-ring locations. Second, the adapter has locations for two orifice plugs, one on either
side of the adapter.
Injector Cup - It has a revised style cup, with a larger diameter tip that improves strength and
reliability.
Injector Cup Retainer - This was designed to accommodate the revised style cup and to
improve ease of assembly.
Injector Plunger - The plunger blank is longer than the previous K STC plunger blank. The
length was added to the minor diameter areas to allow more fuel capacity.
Injector Plunger Coupling - The injector plunger coupling is shorter than the previous K STC
plunger coupling to compensate for the longer plunger blank. The overall length of the two
different plunger and coupling assemblies after crimping is approximately the same. Previous
injector plungers are not interchangeable with the new style.
Internal Plunger Link - A revised internal link was fitted. It is shorter than the internal K STC
plunger link in order to compensate for the longer injector plunger. The overall length of the
revised link is 59.31 mm [2.335 in].
Injector Plunger Return Spring - The injector utilizes a revised plunger return spring due to
the higher travel requirements.
Press-Fit plungers and ceramic inner links were released for the standard K STC injector
assemblies. The combination of these two features improves injector reliability and durability.
Press-Fit plunger assemblies have a stronger joint between the coupling and plunger.
A revised oil feed locknut and top-stop screw were released for K STC injectors. The revised oil
feed locknut has the appropriate total travel settings stamped on it. The revised top-stop screw is
1.78 mm [0.070 in] longer than the previous top-stop screw.

In the STC injector, injection timing is controlled by the STC hydraulic tappet. The tappet has an
inner piston (plunger) and an outer piston (sleeve).
Note : The plunger and sleeve are machined to very precise tolerances. The
assembly is matched by a selection process at the factory (match-fit). Never exchange
or combine the plungers and the sleeves.
These tappet components work together with the injector plunger to control injection timing. The
tappet assembly can be used with any STC top-stop nut because they are not matched.
The tappet assembly and injector are not matched sets. The tappet assembly can be used in any
STC injector. Cummins Inc. recommends STC tappet disassembly only if there is evidence that
debris caused by an engine failure has moved beyond the full-flow filters. Any debris in the tappet
will lower the performance of the tappet.

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The method of adjusting the injection timing and injector rocker lever travel on engines with STC
is the same as the method on engines without STC. The specification for injector travel and
injection timing on engines with STC is different than engines without STC.

The Premium K STC injector assembly supersedes and obsoletes all Standard and Family K
STC injector assemblies.
This injector includes the following features:
Press-fit barrel and plunger assembly
Longer barrel
Revised oil feed locknut
Revised top-stop screw
Ceramic inner link
Stronger cup.
The revised injector is more reliable and durable than the Standard and Family K STC injectors
without the press-fit barrel and plunger assembly and ceramic link.
Standard K STC injectors can not be converted to a Premium K STC injector. Very few parts are
interchangeable. The full injector assembly must be replaced.
Family K STC injectors can be converted to Premium K STC. However, no reliability or durability
improvement will be gained if the Family K STC injectors have press-fit barrel and plunger
assemblies and ceramic links. Press-fit barrel and plunger assemblies and ceramic links are
available for Family K STC injectors.

with Electronically Actuated Injector

 CAUTION 
Do not reuse the injector hold-down capscrew or injector
combustion seal. The reuse of these components can
result in engine damage.

The injector consists of the following components:

1. O-ring/damper
2. Capscrew
3. Injector hold-down clamp
4. Seal
5. O-rings
6. Injector.

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Initial Check
with Electronically Actuated Injector
Misfire Using Heat Indicator Marker
Note : This procedure will possibly not be effective
when the symptoms occur only at low idle or when the
engine is cold.
If the engine exhibits symptoms of a possible injector not firing,
perform the following check:
Operate the engine to normal operating coolant
temperature of 80°C [180°F].
Stop the engine and allow the exhaust manifold to cool for
10 minutes.
Use a 204°C [400°F] temperature indicator marker, Part
Number 3165163, to apply a mark (1) on the surface of all
exhaust manifold ports. The mark must be as close to the
cylinder head as possible, but not directly on the exhaust
manifold mounting flange.
Start the engine and operate under light load for a short
time. Do not operate the engine under heavy load or for
an extended period of time, as this can cause inaccurate
results.

Note : It is not recommended to use the temperature

indicator markers to troubleshoot for cylinders that are
operating too hot.
If the 204°C [400°F] mark melts (1) the color will disappear and
leave only a transparent glazed appearance where the mark
was. This indicates that the cylinder is operating at a
temperature above 204°C [400°F].
If the 204°C [400°F] mark does not melt (2) the mark color
remains present. This indicates that the cylinder is not
operating at or above a temperature of 204°C [400°F],
indicating a possible injection malfunction.
Reference the Engine Performance Troubleshooting Tree for
additional troubleshooting information.

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with Electronically Actuated Injector

Misfire Using Injector Testor Tool
Note : This test must be performed with the engine
shut down for at least 5 minutes.
Note : If the engine is equipped with CM2150 ECMs
(1), cover the plug with a lint-free cloth. Slowly loosen
the plug on the last injector of the high-pressure fuel
lines 1/4 to 1/2 turn. The plug does not need to be
removed to relieve the pressure. Connect INSITE™
electronic service tool and verify the fuel pressure has
bled down by monitoring the fuel rail pressure.

If the engine exhibits symptoms of an injector not firing,

perform the following check using the Injector Tester (1)(2),
Part Number 2892293:
1. Plug the tool harness into the injector tester tool via the 4-
pin connector.
2. Plug the tool harness into the engine harness via the 9-pin
connector.
3. Verify the injector tester tool's yellow READY light is
illumintated. If not, verify power supply to the 9-pin
connector. If illuminated, proceed.
4. Turn the keyswitch ON.
5. Plug the tool harness into injector via the 2-pin connector.
6. Fully depress and release the injector tester tool's PRESS
TO TEST button.
If the green PASS light is illuminated, the injector is
functioning.
If the red FAIL light is illuminated, the injector is failed and
must be replaced.
Repeat steps 5 and 6 until all injectors have been tested.

Misfire Using Infrared Thermometer

If the engine exhibits symptoms of a injector not firing, perform
the following check:
Operate the engine to normal operating coolant
temperature of 80°C [180°F].
Once the engine has reached normal operating
temperature, continue operating the engine and perform
the following check.

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Use an infrared thermometer, Part Number 3164487 or

equivalent, to measure and record the surface temperature of
the exhaust manifold ports.
Note : It is important to measure as close to the cylinder
head as possible and in the same location on each of
the exhaust manifold ports.
If an exhaust manifold port surface temperature is more than
40°C or 72°F (for electronically actuated injectors) or 93°C or
167°F (for mechanically actuated injectors) colder than the
average surface temperature of all exhaust ports, this indicates
a possible injector malfunction.

High-Pressure Injector Return Flow Test

with Electronically Actuated Injector
Remove the injector drain flow hose from the fuel drain
manifold block located on the left bank of the engine. Remove
the hose from the drain manifold block end (1) only. Refer to
Procedure 006-013 in Section 6.
(/qs3/pubsys2/xml/en/procedures/28/28-006-013.html)
The union fitting in the fuel drain block must be capped to
prevent fuel leakage during the test. It can be capped with Part
Number 3164801, or equivalent.

Run the injector drain flow hose into a graduated cylinder to

collect drain fuel flow. The cylinder must be capable of holding
at least 300 ml [10 oz].

Disconnect each of the individual 2-pin injector electrical

connectors (12 for QSK38 and 16 for QSK50). Use the
following procedure in the QSK38, QSK50, and QSK60
(CM850 Modular Common Rail System) Troubleshooting and

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Repair Manual, Bulletin 4021533. Refer to Procedure 019-043

in Section 19 (/qs3/pubsys2/xml/en/procedures/122/122-019-
043.html).

With the return flow hose routed to the graduated cylinder,

crank the engine at a minimum of 150 rpm for 30 seconds in
10 second intervals.

 CAUTION 
Do not overheat the starters. Damage to the starters can
result.

The volume of fuel collected during the 30 second crank cycle

must be less than the volume indicated in the table below.

Measured Return Flow

Engine Volume
QSK38 150 ml [5 oz]
QSK50 200 ml [6.75 oz]

Remove the cap from the male union and install the fuel drain
hose at the fuel drain block.
Tighten the hose.
Torque Value: 45 n•m [ 33 ft-lb ]

High-Pressure Injector Return Flow Isolation Test

with Electronically Actuated Injector
Drain the LTA cooling system. Refer to Procedure 008-018 in
Section 8. (/qs3/pubsys2/xml/en/procedures/28/28-008-018-
tr.html)

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Remove the intake manifolds. Refer to Procedure 010-002 in

Section 10. (/qs3/pubsys2/xml/en/procedures/28/28-010-002-
tr.html)

Install the fuel drain hose on cylinder number 1 LB in place of

the banjo bolt through the fuel drain line that routes to the fuel
drain block. The fuel drain hose for the QSK38 and QSK50 is
Part Number 4918679.
Place the end of the fuel injector drain line fuel return flow hose
in a small graduated cylinder to collect return flow.

Disconnect each of the individual 2-pin injector electrical

connectors (12 for QSK38 and 16 for QSK50). Use the
following procedure in the QSK38, QSK50, and QSK60
(CM850 Modular Common Rail System) Troubleshooting and
Repair Manual, Bulletin 4021533. Refer to Procedure 019-043
in Section 19. (/qs3/pubsys2/xml/en/procedures/122/122-019-
043.html)

With the return flow hose routed to the graduated cylinder,

crank the engine at a minimum of 150 rpm for 30 seconds in
10 second intervals.

 CAUTION 
Do not overheat the starters. Damage to the starters can
result.

Record the amount of fuel collected.

Swap the fuel drain hose and banjo bolt between cylinders 1
LB and 2 LB.
Place the end of the fuel injector drain line fuel return flow hose
in a small graduated cylinder to collect return flow.
Crank the engine at least 150 rpm for 30 seconds in 10 second
intervals.

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 CAUTION 
Do not overheat the starters. Damage to the starters can
result.

Record the amount of fuel collected.

Repeat the previous step until drain flow has been recorded for
all cylinders on both banks.

Measurements
ml fl-oz
Isolated Injector
Return Flow
with Engine
15 0.5
Cranking at 150
rpm for 30
Seconds
 CAUTION 
Do not overheat the starters. Damage to the starters can
result.

Replace injectors on any cylinder that has more leakage than

specified above.
If any injectors were replaced, repeat the test on each of the
cylinders until all cylinders have less flow than specified.

Remove the fuel drain hose and assemble the fuel drain lines.
Refer to Procedure 006-013 in Section 6
(/qs3/pubsys2/xml/en/procedures/28/28-006-013.html).
Install the intake manifolds. Refer to Procedure 010-002 in
Section 10. (/qs3/pubsys2/xml/en/procedures/28/28-010-002-
tr.html)
Fill the cooling system. Refer to Procedure 008-018 in Section
8. (/qs3/pubsys2/xml/en/procedures/28/28-008-018-tr.html)

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Preparatory Steps
with Mechanically Actuated Injector
Remove the rocker lever cover and all related parts. Refer
to Procedure 003-011 in Section 3.
(/qs3/pubsys2/xml/en/procedures/28/28-003-011-tr.html)
Remove the rocker lever assembly. Refer to Procedure
003-009 in Section 3.
(/qs3/pubsys2/xml/en/procedures/28/28-003-009-tr.html)

with Electronically Actuated Injector

Remove the injector fuel supply lines. Refer to Procedure
006-051 in Section 6.
(/qs3/pubsys2/xml/en/procedures/28/28-006-051-tr.html)
Install the injector protective plugs, Part Number 4918767.
Remove the two-piece rocker lever cover. Refer to
Procedure 003-011 in Section 3.
(/qs3/pubsys2/xml/en/procedures/28/28-003-011-tr.html)

Remove
with Mechanically Actuated Injector

Note : This step applies to engines equipped with STC

injectors.
Remove the STC banjo connector mounting screw.
Remove the banjo connector.
Remove and discard the sealing washer (48) and o-ring (49).

Remove the injector hold down capscrew.

Remove the injector hold down clamp. Non STC only.

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 CAUTION 
Do not allow the STC tappet to fall out of the injector.
Engine damage can result.

Note : The rocker lever housing has been removed

from the illustration for clarity.
For top-stop injectors, use injector puller, Part Number
3376497.
Make sure the puller arms are firmly under the top-stop
screws.
Tighten the clamping ring (1).
Use the slide hammer to remove the injector.

For standard injectors, use injector puller, Part Number

3376000 or 3376497.
Place the split collar over the injector.
Slide the locking collar over the injector
Use the slide hammer to remove the injector.
Note : If the injector pullers mentioned above are not
available, carefully use a pry bar. Pry upward in the
injector against the cylinder head.

with Electronically Actuated Injector

 CAUTION 
Do not reuse the injector hold-down capscrew or injector
combustion seal. The reuse of these components can
result in engine damage.

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Note : Do not reuse protective plugs. The protective

plugs must be used immediately upon removal from the
plastic wrapping. If they are not used immediately, the
protective plugs must be discarded. If the protective
plugs are fouled in any manner before use, the
protective plugs must be discarded and a new set
used.
If not already completed, plug the ports in each side of the
injector T-fitting with the injector protective plugs before
removing the injector. Make sure the plugs are wedged firmly
into place. This will prevent debris from entering and causing
damage to the injector.

 WARNING 
To reduce the possibility of personal injury, place a clean
rag around the injector as well as wear goggles or a face
shield to prevent injury from fuel spray from residual fuel
pressure while removing the injector.

 WARNING 
The pressure of the fuel in the line is sufficient to
penetrate the skin and cause serious personal injury.
Wear gloves and protective clothing.

Note : On applications with high drain head pressure,

such as a fuel tank mounted higher than the engine,
shut off the fuel drain line valve and evacuate the fuel
drain line of fuel before removing the injector.
Remove and discard the injector hold-down capscrew.
Use a heel bar to remove the injector. Place the heel between
the injector body and the exhaust rocker lever and gently pry
the injector from the injector bore.
Note : On applications with high drain line head
pressure, such as a fuel tank mounted higher than the
engine, it is possible for fuel to leak from the drain line
into the cylinder when the injector is removed. After
removing the injector, check for fuel dripping into the
cylinder and evacuate the fuel before continuing in the
removal procedure.

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Cover the injector bore in the cylinder head to prevent foreign

objects from entering and possibly damaging the bore and
combustion chamber.

Remove and discard the seal on the end of the injector.

Remove and discard the two o-rings on the injector.

Do not remove the o-ring/damper at this time.

Clean and Inspect for Reuse

with Mechanically Actuated Injector
 WARNING 
When using solvents, acid, or alkaline materials for
cleaning, follow the manufacturer's recommendations for
use. Wear goggles and protective clothing to reduce the
possibility of personal injury.

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 WARNING 
Wear appropriate eye and face protection when using
compressed air. Flying debris and dirt can cause personal
injury.

 CAUTION 
Injector plungers and barrels have a precise fit and are
damaged easily. Only trained technicians are authorized
to remove the plungers. Do not allow the plunger to fall
out of the injector.

Note : Sealing rings are available in different

thicknesses to adjust the injector protrusion.
Remove the o-rings (1), (2), and (3).
Remove the sealing ring (4) and record the thickness.
Clean the exterior of the injector with a lint free cloth.
Check the area that makes contact with the injector.
Check the orifice screen (5). It must be clean. If there is debris
on the screen, remove the retaining clip and the screen for
cleaning.
Clean the screen in solvent and dry with compressed air.
Install the screen and retaining clip.

with Electronically Actuated Injector

 WARNING 
When using solvents, acids, or alkaline materials for
cleaning, follow the manufacturer's recommendations for
use. Wear goggles and protective clothing to reduce the
possibility of personal injury.

Clean the injector assembly with electrical contact cleaner, Part

Number 3824510, or equivalent. Allow to air dry completely.
Do not use compressed air to dry or clean the injector.

Inspect the nozzle tip for damage.

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Replace injectors with damaged nozzles that prevent fuel

delivery into the combustion chamber.
If the injector tip is damaged, inspect the cylinder bore and
combustion chamber for damage as well.

Inspect the injector body for signs of corrosion, cracks, or any

other damage.
Inspect the o-ring grooves for damage that does not allow the
o-rings to seal properly.

Inspect the T-fitting on top of the injector where the injector

supply lines attach.
Inspect for corrosion, cracks and other damage that does not
allow for proper sealing of the injector supply lines.
Replace damaged injectors.

Inspect the o-ring/damper for wear, cracks, or other damage.

Replace, if damaged.

If the valve cover shows signs of oil leakage around the

injector, replace the o-ring/damper.
Inspect the injector wiring for damaged wires, shrink tubing,
elbow, and connector.

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Calibrate
with Mechanically Actuated Injector

Note : The following information for the Mechanically

Actuated Injector applies to the step timing control
injector for the K38 and K50 engines.
This procedure requires special equipment and must be done
at a Cummins® Authorized Repair Location.

with Electronically Actuated Injector

Calibration is not required for the Modular Common Rail Fuel
System.

Install
with Mechanically Actuated Injector
Identify the o-rings so they can be installed in the correct
groove.
O-ring (1) has a red dot or stripe and is dull gray in
appearance.
O-ring (2) has no markings.
O-ring (3) has a green dot or stripe. The o-ring has a shiny
black appearance.
Lubricate the o-rings with vegetable oil and install them in the
appropriate location.
Install the proper size seal ring (4).

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Position the standard injector in the bore. Turn the injector so

that the injector screen points towards the hold down capscrew
hole on the intake side of the cylinder head.
Note : Full top-stop injector and early top-stop injector
plunger travel can only be adjusted when the injectors
are removed from the engine. Use adjusting tool, Part
Number 3822696, to set the injectors.

Do not allow the STC tappet to fall out of the STC (top-stop)
injector. Damage can result.
The STC tappet must be near the rocker lever assembly.

Do not push the injector on the seat until it is correctly aligned.

Place the STC injector in the bore. Turn the injector so the hole
in the top-stop screw points to the oil supply hole in the rocker
lever housing.
Use the oil jumper tube and the connector screw as tools. Turn
the injector until the holes are aligned. Remove the connector
screw and the tube.

 CAUTION 
Do not use a wooden tool to push the injector onto the
seat. Failure can result because of splinters falling into
the tappet.

Apply a quick hard push with a blunt object that touches the
top-stop screw to seat the injector.
A single snapping sound will be heard when the injector is
seated properly.

Install the hold-down clamp and the self-locking capscrews.

Tighten the capscrews alternately and evenly so the clamp will
be centered on the injector body.
Torque Value: 16.2 n•m [ 145 in-lb ]

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Note : Engines equipped with STC injectors, have the

hold down clamp already fitted to the injector.

Install the o-ring (1) on the jumper tube. Lubricate the o-ring
with clean engine oil. Install the jumper tube and the copper
sealing washers (2).
Install the connector screw and tighten.
Torque Value: 25 n•m [ 221 in-lb ]
Note : The oil jumper tubes for full stop STC injectors
are 8 mm [5/16] shorter.

with Electronically Actuated Injector

If the o-ring/damper is damaged, install a new o-ring/damper
on the injector.

Install the new o-rings on the injector body.

Install the new seal on the end of the injector.

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13/7/2018 Injector

 WARNING 
Some solvents are flammable and toxic. Read the
manufacturer's instructions before using.

 WARNING 
When using solvents, acids, or alkaline materials for
cleaning, follow the manufacturer's recommendations for
use. Wear goggles and protective clothing to reduce the
possibility of personal injury.

 WARNING 
Wear appropriate eye and face protection when using
compressed air. Flying debris and dirt can cause personal
injury.

 CAUTION 
Do not reuse the injector hold-down capscrew or injector
combustion seal. The reuse of these components can
result in engine damage.

 CAUTION 
Keep the injector bore and combustion chamber
protected when using compressed air to prevent
contamination. Failure to do so can cause engine
damage.

Note : On applications with high drain line head

pressure, it is possible for fuel to leak from the drain line
into the cylinder when the injector is removed. Before
installing the injector, check for fuel dripping into the
cylinder and evacuate the fuel before installing the
injector.
Clean the injector bore in the cylinder head with electrical
contact cleaner, Part Number 3824510, or equivalent, for
proper sealing of the o-rings.

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13/7/2018 Injector

Clean the threaded hole in the cylinder head where the injector
hold-down capscrew will be installed with electrical contact
cleaner, Part Number 3824510, or equivalent, and compressed
air.

Lubricate the threads and underside of the new injector hold-

down capscrew with clean lubricating engine oil.

Lubricate all the o-rings with a light coating of clean lubricating

engine oil.

 CAUTION 
Do not reuse the injector hold-down capscrew or injector
combustion seal. The reuse of those components can
result in engine damage.

Assemble the injector hold-down clamp and capscrew into the

injector.

 CAUTION 
Only use a soft face mallet. Otherwise damage to the
injector can occur.

The injector installer can be used on single or multiple injector

installations.
Install the assembly into the cylinder head by tapping gently on
the injector with a soft face mallet.

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13/7/2018 Injector

Assemble the injector installer kit, Part Number 4918620.

Finger tighten the three shoulder capscrews.

Place the injector installer on the injector such that the ball
spring plunger on the installer is on the tapered side of the
injector (1). If necessary, adjust the ball spring plunger so that
it presses against the injector. Make sure the flat side of the
injector (2) sits flush with the injector installer.

Align the injector installer with two injectors.

Tighten the three shoulder capscrews.

The 60 degree torque angle can be achieved by marking the

location of one corner of the capscrew to a location on the
injector hold-down clamp.
Torque Value:
Injector Hold-Down Clamp Capscrew
1. 68 n•m [ 50 ft-lb ]
2. Loosen capscrew completely.
3. 30 n•m [ 22 ft-lb ]
4. Rotate the capscrew 60 degrees.

Finishing Steps
with Mechanically Actuated Injector

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13/7/2018 Injector

Install the rocker lever assembly. Refer to Procedure 003-

009 in Section 3. (/qs3/pubsys2/xml/en/procedures/28/28-
003-009-tr.html)
Adjust the overhead. Refer to Procedure 003-006 in
Section 3. (/qs3/pubsys2/xml/en/procedures/28/28-003-
006-tr.html)
For STC Injectors, adjust the overhead. Refer to
Procedure 003-007 in Section 3.
(/qs3/pubsys2/xml/en/procedures/28/28-003-007-tr.html)
Install the rocker lever cover and all related parts. Refer to
Procedure 003-011 in Section 3.
(/qs3/pubsys2/xml/en/procedures/28/28-003-011-tr.html)
Operate the engine and check for leaks.

with Electronically Actuated Injector

Adjust the valves. Refer to Procedure 003-006 in Section
3. (/qs3/pubsys2/xml/en/procedures/28/28-003-006-
tr.html)
Install the two-piece rocker lever cover. Refer to
Procedure 003-011 in Section 3.
(/qs3/pubsys2/xml/en/procedures/28/28-003-011-tr.html)
Remove the injector protective plugs, Part Number
4918767.
Install the injector fuel supply lines. Refer to Procedure
006-051 in Section 6.
(/qs3/pubsys2/xml/en/procedures/28/28-006-051-tr.html)
Operate the engine and check for leaks.

Last Modified: 20-Apr-2018

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