Yanmar 6CXM-GTE, 6CXM-GTE2 Service Manual

M9961-H13021

SERVICE MANUAL

MARINE DIESEL ENGINE

6CXM-GTE/GTE2

Revision history list Page No. 1

Document name SERVICE MANUAL FOR YANMAR MARINE DIESEL ENGINE

Product name 6CXM-GTE/GTE2

Literature No. M9961-H13021

Revision No.

Rev.1 November, 05 To add more details of

Revision date

Reason for revision Revision outline

fuel injection pump

3.11 Fuel Oil System
was increased.

Revised item

(page)

From page 3-29
to page 3-43-24

Revised by

Marine Business
Development Dept.

- i -

3.11 Fuel Oil System

The engine revolutions are transmitted to the camshaft by
the driving gear of the fuel pump via the timer.
The feed pump activated by the camshaft rotations sucks
fuel oil from the fuel tank and feeds it to the fuel filter at the
pressure of about 0.33 MPa (3.4 kgf/cm
The filtered fuel oil is sent to the oil sump in the pump
housing and is pressurized by the plunger. The fuel oil then
flows through the injection pipe and nozzle holder and is
injected from the nozzle to each cylinder.

2

).

Automatic timer

3.11.1 Fuel Injection Pump

The Yanmar YPES-PS fuel injection pump is an integrated
type and the engine revolutions are transmitted to the cam­shaft of the pump through the driving gear and advance timer.

(1) Specifications

/st

6CXM-GTE/

6CXM-GTE2

70

36.7 (3.74)

9.26 (0.944)

Unit

Plunger dia. mm 13

Plunger pre-stroke mm 3.5

Delivery valve suck-back q'ty

Delivery valve dia. mm 7

Cam lift mm 12

Thrust clearance mm 0.01 - 0.05

Plunger spring free length mm 54

Plunger spring constant

Delivery valve spring free length mm 21

Delivery valve spring constant

3

mm

N(kgf)/mm

N(kgf)/mm

Fuel injection pump

Fuel feed pump

Boost compensator

Governor

Damping valve

Delivery valve

Plunger barrel

Plunger

Control rack

Tappet

Fuel cam

(YPES-PS type)

- 3-29 -

(2) Feature

The fuel injection pump supplies pressurized fuel to the
injection nozzles through the action of the plunger.
The plunger reciprocates in the plunger barrel with a
fixed stroke and is lapped for a precise fit.
A lead groove is helically cut in the plunger, and this
leads to a connecting groove which rises to the top of the
plunger.
The integrate plunger barrel, the plunger barrel and the
flange case for the delivery valve holder, equips a port for
intake and discharge.
The injection volume of individual cylinders can there­fore be adjusted by rotating the plunger.
The fuel comes through this port into the plunger chamber
is pressurized by the plunger, opens the delivery valve,
flows to the fuel injection nozzle through the fuel injection
pipe and is injected into the combustion chamber. Fuel
injection ends when the pressurized fuel has been dis­charged.
This happens when the lead groove lines up with the port,
(as the plunger rises and the pressure in the fuel injection
pipe drops).

(3) Injection volume control

The fuel control mechanism is shown in following fig.
The T-shaped flange at the bottom of the plunger is fixed
in the grooves of the pinion sleeve, and the pinion is
engaged to the control rack. The plunger rotates at the
same time as the control rack is moved, adjusting the
effective stroke and controlling the injection quantity.

A fuel leak return hole is provided in the plunger barrel. This
returns fuel which leaks through the gap between the plunger
and the barrel to the fuel drain sump through the drain pipe,
preventing dilution of the lubricant in the cam chamber.

1) Full injection volume position

When the rack is set at maximum setting, maximum
volume of fuel is discharged. Injection occurs when
the top of the plunger lines up with the intake port in
the barrel. At this time, the lead groove which is posi­tioned at the widest stroke part, lines up with the dis­charge port, prolonging the injection time and
increasing the volume of fuel injected.
This setting is normally used for starting and max. out­put operation.

- 3-30 -

2) Half injection volume position

Discharge ends earlier as the rack is moved towards
zero from the maximum setting.
The fuel injection volume is decreased accordingly.

At the same time, the suck-back collar (1) blocks off the
fuel injection pipe and the delivery chamber, and the
valve continues descending until the seat (2) comes in
contact with the barrel.
The fuel oil pressure in the fuel injection pipe decreases
proportionately with the lowering of the valve (due to
increased volume).
This accelerates the nozzle to the nozzle valve, and sucks
up fuel from the nozzle to prevent dripping.
The result is a longer nozzle life and improved combus­tion efficiency.

3) No fuel injection

With the rack set near zero, the intake/discharge port
in the barrel is always open, so no fuel is pressurized
(even though the plunger continues to reciprocate).

(4) Delivery valve

The delivery valve at the top of the plunger prevents fuel
in the fuel injection pipe from flowing back to the
plunger chamber and sucks up fuel from the nozzle valve
to prevent after-drip.
When plunger lead lines up with the discharge port of the
plunger barrel, the injection pressure drops, and the deliv­ery valve is brought down by the delivery valve spring.

(5) Injection wave damping valve

The injection wave damping valve is fitted inside the
delivery valve holder. This valve prevents the cylindrical
pressure from being raised again by the injection reaction
and thus prevents secondary injection and cavitation.

- 3-31 -

3.11.2 Governor

(1) Feature

The two-point weight centrifugal type all speed control governor is directly coupled with the fuel pump. The governor
weight assembly, driven by the pump shaft end, controls the control rack of the fuel pump to adjust the fuel injection quan­tity.

1) Condition during engine start
When the control lever is pulled to the starting position, the governor weights are closed by the force of the governor
spring, and the linkage connected to the shifter moves the control rack to the maximum injection position.

2) Conditioning during idling
As the engine starts and the control lever is returned to the idle position, the spring retainer returns and the governor
spring force is reduced.
The governor weights are opened by the centrifugal force and push the control rack to reduce the fuel. The weight force is
balanced with the spring force to maintain the idling speed.

3) Condition during maximum speed
When the engine reaches its maximum speed, the weight force is balanced with the governor spring force and the rack is
kept at the appropriate injection position. If the engine load is reduced, the engine speed increases and the governor
weights open. The rack is then moved to reduce the engine speed, to return it to the specified maximum. The maximum
fuel quantity is limited by the fuel injection limit screw. Do not try to adjust the injection limit screw except when neces­sary since it is sealed.
When the stop lever is turned to the stop position, the control rack is moved to the stop position,
regardless of the governor spring force, and stops the engine.

4) Damper spring
To prevent engine stoppage on sharp engine speed reduction, damper spring is equipped.

- 3-32 -

(2) Reversed angleich mechanism

The CXM model employs the high pressure fuel injection pump to match with its high output structure.
When using the high pressure pump, however, the injection volume at the equalized rack condition tends to
decrease according to the rise of engine speed. Accordingly, a larger capacity pump is used.
The use of a large capacity pump, however, gives over-torque and adverse exhaust color due to excessive fuel injection dur­ing medium speed high load operation. To prevent this and to control fuel injection volume at the medium high load opera­tion to the proper level, the reversed angleich mechanism is used for the governor.

- 3-33 -

1) Before starting

"

The starting fuel increase spring let the governor
lever move to the "fuel increase" side to raise the
starting performance.

2) After starting

The starting fuel increase spring is compressed by
the thrust force of the governor to stop the starting
fuel increase.

3) Max. speed

Thrust force of the governor increases according to
the rise of revolutions and the fuel is increased until
the reversed angleich spring is completely com­pressed.
(This is the max. injection position.)
To explain the function more concretely, during the
medium to high load operation, even if the tension
lever contacts the fuel limiter and the rack is at the
max. position, the reversed angleich spring overcomes
the thrust force of the governor since the revolution is
below the max. speed and caused the governor level to
move to the fuel decrease side by the distance of the
control q'ty (
nism, which limits the fuel injection q'ty during
medium to high load operation for preventing "over­torque" and adverse exhaust color.

). This is the reversed angleich mecha-

- 3-34 -

3.11.3 Boost Compensator

The boost compensator, installed to the injection pump of the turbocharged engine models, limits the movement of the fuel con­trol rack with the boost pressure detection equipment. It optimizes fuel injection and combustion according to the air volume
inside the cylinder for complete combustion and higher output.

(1) Performance

Without boost compensator

With boost compensator

Rack position and boost

2

R

R

3

1

R

Rack position

R

0

R

P

pressure linear diagram
when engine speed is
raised gradually

P

B

P

A

Boost pressure

1

NNN

0

Idle

Engine speed

2

Boost pressure linear diagram
at quick accelaration

1) The solid line shows the rack's moving distance and the boost pressure when the engine speed is raised gradually.

2) When the regulator handle is raised quickly from the idling position (N0) to the (N1) position, the rack moves from R0 to
R2 to attain the engine speed (N1), and injects a large quantity of fuel. The supply of air, however, is inadequate due to the
follow-up delay of the turbocharger (i.e. insufficient boost pressure), and the exhaust turns black.

3) The boost compensator limits the advancing of the rack and keeps it at R3 position. The rack starts to move at pressure of
PA and reaches to R2 position when pressure rises up to PB or more.

4) In engines with the boost compensator, injection quantity in the range of rack positions R2 - R3 (shadowed area) is lim­ited and thus black exhaust is controlled.

(2) Equipment

When the regulator handle is operated quickly for acceleration, the control rack moves to the fuel increase side and touches
the boost compensator lever (A) to limit the rack's stroke. This position is the point where about 70% of the max. injection
quantity is obtained. (Fine adjustment is possible by the adjust screw.)

- 3-35 -

When the turbocharger catches up the engine speed and the boost pressure is raised, the diaphragm is pressed by the charg­ing pressure, causing the boost compensator's lever to move to turn the control rack to the fuel increase side: max. injection
quantity is obtained.

- 3-36 -

3.11.4 Disassembly of Governor

The fixing wire and seal are attached to the governor to limit
engine speed and output for protecting the engine.
Do not disassemble and adjust the limit unless it is unavoid­able. Faulty adjustment of the governor will lead to engine
failure.

1) Remove the governor case cover.

2) Remove the reverse angleich mechanism.

8) After removing the o-ring, lightly tap another end of the
shaft, and remove the governor lever shaft. Then remove
the governor shaft assembly and washer.

9) Unhook the governor spring from the tension lever and
control lever shaft.

3) Remove the governor case bolt. Remove the governor
case (parallel pin) from the spacer of the fuel pump side
while lightly tapping the governor case with a wooden
hammer.
Make a gap between the governor case and spacer by
moving only the moving parts of the governor cover.

4) Remove the connecting spring by inserting needle nosed
pliers between the governor case and spacer.

5) Slide the governor case and pull out the link pin of the fuel
control rack.

6) Remove the snap-rings on both ends of the governor lever
shaft.

7) Put a rod (10 mm (0.3937 in.) or less diameter) on one end
of the governor lever shaft, and tap it until the O-ring
comes out from other side of the governor case.

10)Pull out the governor sleeve at the end of the fuel cam­shaft by hand.

- 3-37 -

11)Remove the governor weight nut and washer with a box
spanner, fixing the fuel camshaft by the hole of the fuel
pump coupling or holding the coupling with a vice.
Screw the governor weight nut back in two or three
times.

12)Remove the governor weight assembly from the fuel
camshaft. Use the governor pulling tools.

3.11.5 Inspection of governor

Inspect the following points when disassemble the governor.

Check item Allowance Repair

Wear & excessive clearance of governor

1

weight pin & pin hole

Contact surface of governor sleeve with

2

weight roller.

3 Thrust bearing No seizure, discoloration, or breakage Replace the thrust bearing.

4 Free length, fall of governor spring

5 Wear, distortion of lever shafts No excessive clearance and distortion Replace the shaft.

6 Oil leakage to outside No oil oozing out and leakage Replace the packing, O-ring.

Within the standard clearance of 0.2mm and
should move smoothly.

No excessive wear. Replace the sleeve.

Free length: Within 68 mm (Standard 65 -

65.5 mm)

Replace the governor weight cmp.

Replace the governor spring.

- 3-38 -

3.11.6 Reassembly of governor

Inspect all parts after disassembly and replace any parts as
necessary. Before starting reassembly, clean both the new
parts and parts to be reused, and put them in order.
Be sure to readjust the unit after reassembly to obtain the
specified performance.

1) Insert the governor weight assembly to the taper portion at

the end of the fuel camshaft.
Fix it by the hole of the fuel pump coupling or by holding
the coupling with a vise.
Mount the conical spring washer, and tighten the governor
weight nut.

4) Mount the governor link to the governor lever assembly.

Note:

1.Make sure that the correct governor link
mounting holes are used, and that it is
mounted in the correct direction.

2.Make sure that the governor link moves
smoothly.

5) Put the governor lever shaft assembly in the governor
case, insert the governor lever shaft until the O-ring
groove come out from the opposite side of the governor
case, and fit the O-ring.

Governor weight tightening torque

59 - 69 N-m

(6 - 7 kgf-m)

2) Open the governor weight and insert the sleeve in the end
of the fuel camshaft.

Note:

1.Fit the O-ring to the side you tapped it in
from.

2.Coat the O-ring with the silicon oil for protec­tion during insertion.

3.Don't forget to place washers on both sides of
the governor lever.

6) After mounting the O-ring, tap the governor lever in the
opposite direction, and mount the E-shaped stop rings on
the grooves at both ends.

Note: Make sure that the sleeve moves smoothly after

insertion.

3) When the control lever shaft has been removed, lightly tap
the control lever shaft and washer from inside the gover­nor case, using an appropriate plate.

- 3-39 -

Note:

After mounting the governor lever assembly,
make sure that it moves smoothly.

7) Hook the governor spring on the pin of the governor lever
and control lever.

8) Insert the rack link in the governor link, hook the link con­necting spring on the spring pin of the governor link side
with the spring set bar, and connect the governor link with
the rack link.

9) Fit the link connecting spring to the spring pin at the rack
link with the spring set bar by pushing the rack link into
the governor link.

10)Mount the governor case to the fuel pump unit, lightly

tapping it with a wooden hammer, and tighten the bolts.

11)Mount the governor case cover.

12)Insert the control lever to the control lever shaft, and

tighten the nut.

Note:

Move the control lever back and forth to make
sure that the entire link moves smoothly.

- 3-40 -

3.11.7 Disassembly of fuel injection pump

When disassembling the fuel injection pump, separate the
parts for each cylinder and be careful not to get them mixed
up.
Be especially careful to keep the plunger/plunger barrel,
delivery valve/delivery valve seat and other assemblies sepa­rate for each cylinder (the parts of each assembly must be
kept together and put them back in the same cylinder).

(1) Preparation

1) Wash off the dirt and grease on the outside of the
pump with cleaning oil (kerosene or diesel oil) before
disassembly.

2) Perform the work in a clean area.

3) Take off the drain plugs and drain the lubrication oil.

2) Screw the puller into the nut hole.
Remove the automatic timer by screwing in the puller
bolt.

3) Remove the spring shoe setting screws of all cylinder.

(2) Disassembly

1) Fix the outside of the automatic timer and remove the
nut.

4) Loosen the delivery valve holders until they can be
turned by fingers.

- 3-41 -

5) Remove the plunger barrel tightening nuts.

9) Remove the delivery valve holder, delivery valve,

valve spring, valve stopper and O-ring from the
plunger barrel.

6) Remove the plunger barrel assembly.
Insert two drivers under the barrel flange. (Be careful
not to damage the surface of the pump housing.)
Lift up the barrel by prying the driver. Pull out the bar­rel by turning it to and fro.

7) Remove and mark the shims to recall the original
assembly.

Note:

Mark each part to recall the original assembly.

10) Remove the straight pins securing the spring shoe to
the barrel support, then remove the pinion.

8) Remove the plunger and plunger barrel together with
the plunger spring and lower spring retainer.

- 3-42 -

11) Remove the rack setting screw and the control rack.

12) Remove the tappets.

15) Remove the cam support and the shims by prying
open the slots in the support with screw drivers.

13) Remove the fuel feed pump.

14) Put the pump body upside down and remove the hex­hollow set bolts that secure the middle bearing.

16) Remove the camshaft together with the middle bear­ing from the drive side.

Note:

Be careful not to damage the governor case oil
seal when removing the camshaft.

- 3-43-1 -

3.11.8 Inspection of fuel injection pump

(1) Inspection of plunger

1) Thoroughly wash the plungers, and replace the plung­ers that have scratches on the plunger lead or are dis­colored.

2) The plunger is in good condition if it slides down
smoothly when it is tilted at about 60q.
Turn the plunger and try this test several times. If the
plunger slides down too quickly or stops part way,
repair or replace it.

(3) Inspection of pump housing

1) Inspect the sliding surface against the tappet guide for
extreme wear. Scratches on the sliding surface against
the roller pin are not a problem.

2) If there are burrs or discoloration, repair or replace the
body as this will lead to dilution of the lubricant.

(4) Inspection of fuel camshaft and bearings

1) Fuel camshaft
Inspect for scratches or wear of cam surface, deforma­tion of key grooves and screw on both ends. Replace it
if necessary.

2) Replace the bearings if the outer race surface are
flaked or worn.

(2) Inspection of delivery valve

1) Clean the delivery valve well before inspection.
Replace as a set if the collar or seat of the delivery
valve is scratched, scored, scuffed, worn etc.

2) The valve is good if it returns smoothly when released
after being pushed down with your finger. (While the
hole at the bottom of the delivery guide seat is cov­ered.) Replace it if necessary. Likewise, the valve
should completely close by its own weight when you
take your finger off the hole at the bottom of the deliv­ery guide sheet.

Note:

When fitting new parts, wash with diesel oil and
perform the above inspection.

Note:

Replace the fuel camshaft and bearings together.

(5) Inspection of tappet

1) Inspect the surface of the tappet, roller and roller pin
for wear or damage. Replace it if necessary.

2) Measure the clearance between the roller and pin.
Replace them if the clearance exceeds 0.2mm.

(6) Inspection of rack and pinion

Inspect the rack and pinion for wear and burrs on tooth
surface. Replace them if necessary.

(7) Inspection of plunger spring and delivery valve

spring

Inspect the spring for scratches, cracks, breakage,
uneven wear and rust. Replace it if necessary.

(8) Inspection of setting screws

Inspect all setting screws and bolts for wear or damage.
Replace it if necessary.

(9) Inspection of oil seal

Inspect the oil seal lips for wear or damage. Replace it if
necessary.

- 3-43-2 -

3.11.9 Reassembly of fuel injection pump

(1) Preparation

1) After inspection, arrange and clean all parts.

2) Prepare the parts for replacement before starting
assembly.

4) Provisionally install the camshaft support.
Sure to use the standard thickness shim.

Standard thrust clearance
of camshaft

0.01 㨪 0.05mm

Note:

Always replace gaskets, packing and O-rings
with new ones.

(2) Assembly

1) Install the governor case to the pump housing.

2) Fit the bearings to both ends of the camshaft. Place the
pump housing upside down and insert the camshaft in
the housing together with the middle bearing.

Note:

Apply grease to the middle bearing to prevent it
from falling out before installation.
Coat the camshaft and oil seal with clean lube
oil to prevent damage to the lip of the oil seal.

Note:

Do not install the O-ring at this stage.
Coat the camshaft and oil seal with clean lube
oil to protect the oil seal from damage.
Take care that the shims do not stick in the O­ring grooves.

5) Tighten the camshaft support with four screws.

6) Tap both ends of the camshaft with a mallet to seat the
bearings.
Turn the camshaft by hand and feel its rotating resis­tance (preload). If it is too heavy, adjust it by adding
shims. Remove the shim if it is too light.

3) Provisionally tighten the middle bearing with hex. hol­low set bolt.

- 3-43-3 -

7) After adjusting the preload, remove the camshaft sup­port and install new O-ring in the groove in the sup­port.

8) Apply clean lube oil to the O-rings, pump housing
bore and the camshaft support.

12) Screw in the spring shoe setting bolts.

Note:

Be careful not to damage the O-rings.

9) Securely tighten the hollow set bolts of the middle
bearing.

Note:

Recheck the bearing preload after tightening the
hollow set bolts, and readjust the preload if nec­essary.

10) Screw in the tappet setting bolts.

11) Align the groove in the tappet with the setting bolt

and insert the tappet.

13) Insert the rack in the pump housing and align its
ninth division of the scale with the end surface of the
pump housing thread.

14) Lock the rack position with a special setting bolts as
shown below.

- 3-43-4 -

15) Install new O-ring in the plunger barrel.

16) Insert the plunger barrel in the deflector and barrel
collar. Align the hole in the barrel with the hole in
the collar, then set the straight pin in the holes of the
barrel and collar to fix them.

17) Insert the pinion in the spring shoe and install the
spring shoe on the barrel collar. Secure the spring
shoe with the straight pins.

20) Hook the neck of the plunger to the spring retainer,
align the plunger flange with the slots in the pinion
and push the plunger until it is locked by the clip ring
on the pinion.

21) Place a shim around each stud bolt.

18) Insert the clip ring into the groove in the pinion.

19) Install the plunger spring.

22) Align the grooves in the pinion and spring shoe.

- 3-43-5 -

23) Align the groove of the spring shoe with the setting
bolt and carefully insert the plunger barrel assembly
in the pump housing bore.

25) Install the delivery valve seat, valve, spring, stopper
and O-ring, then finger tighten the delivery valve
holder.

Note:

Apply clean lube oil to the O-rings and pump
housing bore in order not to damage the O-ring.
Do not try to drive in the barrel.
Before inserting the plunger barrel assembly,
turn the camshaft and set the cam to the position
that the tappet comes to the lowest position.

24) Install the original shims as marked during disassem­bly between the barrel and pump housing.

26) Align the marks on the barrel support and the pump
housing, then tighten the nuts to the specified torque.

Torque

39 㨪 49 N࡮m (4 㨪 5 kgf࡮m)

- 3-43-6 -

27) Tighten the delivery valve holders to the specified
torque.

Torque

98 㨪 118 N࡮m (10 㨪 12 kgf࡮m)

28) Install the fuel feed pump to the pump housing.

29) Remove the rack set bolt and install the rack setting
screw securely.

In each case, disassemble and repair.

31) Assemble the governor.

32) Fill the pump and governor with clean lube oil.

Oil capacity

pump 250 cc

governor 300 cc

30) Hook a spring scale to the control rack and measure
the sliding force.

Sliding force 1472 (150 gf) max.

Excessive sliding force may be caused by the followings.
࡮Large resistance at the sliding section of the plunger

assembly.

࡮Excessive tightening of the delivery valve holder (distor-

tion of the plunger barrel)

࡮Damage or particles at the tooth of the control rack or pin-

ion.

࡮Damage at the outer periphery of the control rack.
࡮Damage at the control rack hole in the pump housing.

- 3-43-7 -

3.11.10 Adjustment of fuel injection pump

Adjust the fuel injection pump after completing reassembly.
The pump itself must be readjusted with a special pump
tester when you have replaced major parts such as the
plunger assembly, tappet assembly, fuel camshaft, etc.

(1) Preparation

Prepare for adjustment as follows.

1) Adjusting nozzle assembly and data sheet of injection

start pressure.

4) Fill the pump and governor with clean lube oil.

oil capacity : pump 250 cc

governor 300 cc

5) Connect the fuel oil pipes and operate the pump tester
to purge the air in the line.

6) Set the oil feed pressure from the pump tester to the
injection pump at the pressure specified in the separate
service data sheet.

Adjusting nozzle type

Injection start pressure

2) Adjusting injection pipe.

Inner dia. / outer dia. x length

Minimum bending radius 25 (0.98)

See (7) Injection adjustment
standard

mm (in)

Ǿ6.35/1.8  600mm

3) Mount the fuel injection pump on the pump tester plat­form.

(2) Adjustment of pre-stroke

1) Remove the delivery valve holder of No.6 cylinder.
Remove the delivery valve spring and delivery valve.

2) Screw the pre-stroke measuring device in the screw
hole on the top of the barrel.

3) Set the control rack to the full load position.
Find the bottom dead center of the plunger while rotat­ing the pump by hand, and set the dial indicator to
zero.

- 3-43-8 -

4) Slowly rotate the pump in the normal rotation direc­tion by hand, and measure the plunger lift until fuel
flow from the overflow pipe on the measuring device
stops.
Pre-stroke : See separate service data

5) If the measured pre-stroke is not standard, adjust by
changing the shim thickness between the flange of the
plunger barrel and pump housing.

6) Repeat the above procedure to adjust the pre-stroke of
each cylinder.

7) After adjustment is completed, insert the delivery
valve, delivery valve holder and spring.
Tighten the delivery valve holder.

(4) Plunger pressure test

1) Mount the pressure gauge to the delivery valve holder
of the cylinder to be tested.

Delivery valve holder
tightening torque

98 㨪 118 N࡮m

(10 㨪 12 kgf࡮m)

(3) Adjustment of injection timing

After adjusting the pre-stroke for all cylinders, check and
adjust the injection timing.

1) Set the governor control lever in the operating position
(bring the plunger to the effective injection range),
then turn the camshaft clockwise, and check the injec­tion starting time (FID) of No.1 cylinder (start of fuel
discharge from the delivery valve holder).

Cylinder No. Count from drive coupling side

Direction of rotation View from drive coupling side

2) Set the tester needle on the flywheel scale in a position
where it is easy to read, and check the injection timing
several times according to the injection order.

Injection order 1-4-2-6-3-5

Injection interval

Allowable deviation

3) Readjust the pre-stroke of cylinders that are not within
the allowable deviation (increase of the adjusting shim
thickness makes the injection timing later, and
decrease makes it earlier).
The change in injection timing by the adjusting shims
is as follows.

Adjusting thickness of shim

0.1 mm (0.0039 in.)

Change of injection timing

Cam angle Crank angle

60q

r 30'

0.35q 0.7q

Max. pressure gauge reading

Connecting screw dimensions

98.1 MPa

(1000 kgf/

M14  1.5

cm

2) Set the governor control lever in the stop position,
operate the injection pump at about 200 rpm, and
make sure that the pressure gauge reading is 49 MPa
(500 kgf/cm

2

) or more. All the time lightly move the
control rack towards fuel increase side.
Replace the plunger if the pressure does not reach this
value.

3) Check to see that oil is not leaking from the delivery
valve holder or fuel injection piping, and there is no
extreme drop in pressure.

(5) Delivery valve pressure test

1) Connect a pressure gauge to the delivery valve holder.
(Refer to plunger pressure test.)Drive the pump at 200
rpm and, moving the control rack, apply a pressure of
12 MPa (120 kgf/cm

2) Set the control rack to the 0 mm position and measure
the time required for the pressure to drop from 10 MPa
(100 kgf/cm

Pressure drop limit 20 seconds minimum

2

) to 9 MPa (90 kgf/cm2).

If the pressure drops faster than this, wash the delivery
valve, and retest. Replace the delivery valve if the
pressure drop is not remedied.

2

).

2

)

Thickness of
shims

Standard 3.0 mm (0.118 in)

2.5 㨪 3.5 mm

Applicable

(0.984 㨪 1.378 in)

(t = 0.1 mm step)

- 3-43-9 -

(6) Measurement and adjustment of injection volume

The injection volume is determined by the fuel injection
pump rpm and rack position. Check and adjust to bring it
to the specified value.

1) Measurement of injection volume.

a) Set the pump rpm, rack position and measuring

stroke to the specified value and measure.

Pump rpm See separate service data

Pump rotation direction View from drive side

Rack indicator scale See separate service data

b) Measure the injection volume at the standard stroke,

and adjust as follows if it is not within the specified
value.

Measuring stroke

Specified injection volume
at standard rack position

Non-uniformity of
cylinders

2) Adjustment of injection volume

a) Loosen the two nuts on the plunger barrel flange,

and turn the plunger barrel to the right or left.

b) Measure the injection volume of each cylinder.

Repeat this process until the injection volume of
every cylinder is within the specified limit.

c) After completing the measurements, retighten the

nuts of plunger barrel flange.

See Standard Adjustment Value

Tab le.

(7) Injection adjustment standard (on engine)

Adjustment procedures

1) Set the initial rack position of the boost compensator
at R=9.0 mm.
(air pressure in the boost air pipe is 0 MPa (0 kgf/cm
Fuel limiter released, regulator at FULL position)

2) Check the limit rack position of the boost compensator.
R>15 [The pressure in the boost compensator piping
line increased : 0

3) Make the following adjustment and air leakage check
of the boost compensator piping under the air pressure
of 0.2 MPa (2 kgf/cm

a) Adjustment of rated injection q'ty
b)Check of injection q'ty at idling condition. ㅜ

c) Setting of reversed "Angleich" reduced injection

ㅝ

q'ty.

d) Check of injection q'ty at reversed "Angleich" range.

ޓ㧘



e) Check of rev. speed to start reversed "Angleich".
f) Setting of high idle injection q’ty. ㅠ

g)Check of regulation

h)Check of injection stop.
i) Check of injection stop when the stop lever is oper-

ated.

j) Check and set the injection q’ty at start.

ψ

0.2 MPa (0ψ2 kgf/cm2)]

2

).

Ԙ







ㅥ

2

).



Tightening torque

39 㨪 49 N࡮m

(4.0 㨪 5.0 kgf࡮m)

d) If match mark is not aligned, make a new match

mark.

- 3-43-10 -

Standard Adjustment Value

Adjustment

Point

Ԙ

Nozzle holder ass'y D27672-53100 D27672-53200 Model 6CXM-GTE 6CXM-GTE2

Nozzle 155S296CZ 155S306CAZ

Nozzle holder PS-SLi High idle

Nozzle opening pres­sure

Transfer pump pressure

FO injection pipe

Fuel oil Diesel oil (JIS No2 equivalent)

Temp of fuel oil

Rack scale

13.5 1425 1450

(5) 350

(11.7) 1000

(11.0) 750 (191) (196)

(12.4) 1175 (198) measure

(4) 1600 1625

(9) 500

(10) 200

Test condition

Pump speed

(rpm)

6CXM-GTE

6CXM-GTE 6CXM-GTE2

6CXM-GTE2

23.5 r 0.5MPa

(240 r 5kgf/

0.05MPa

(0.5kgf/

Ǿ6.35/1.8  600mm

42 r 2 

cm

cm

2

2

)

)

Average injection

q'ty (mm

6CXM-GTE

197 r 3195r 3 r 3

194 r 5199r 5

3

/st)

6CXM-GTE2

10 㨪 20 r 15

10 㨪 20

110 r 5

190 r 10

㧙㧙

Low idle

㧙㧙

㧙㧙

㧙㧙

㧙㧙

Not uniform

Note

%

㧙

㧙㧙

㧙㧙

㧙

㧙㧙

㧙

Engine spec

3200 r 25rpm 3250 r 25rpm

6CXM-GTE

at 2850rpm at 2900rpm

Reversed angleich

750 r 25rpm

6CXM-GTE2

㧙

High idle

Start

4) Make the air pressure in the boost
compensator piping to 0 MPa(0 kfg/cm

2

).

a) Set the reduced injection q'ty of the boost compensator.
b) Raise the air pressure of the boost compensator gradually

from 0 MPa (0 kgf/cm

start pressure.

ㅤ,Ԙ

2

) in order to check the operation

Make the air pressure of the boost compensator piping to
0 MPa (0 kgf/cm

2

).

c) Check and set the increased injection q'ty at starting. ㅥ

ㅣ

- 3-43-11 -

(8) Adjusting points

Setting of injection

11

q'ty at start

9

Setting of reduced injection
q'ty of boost compensator

Adjusting of rated injection

1

q'ty

4

Adjusting of stroke of
reversed "Angleich"

- 3-43-12 -