SEZIONE 1 PAG. 11-24.pdf

7/27/2019 SEZIONE 1 PAG. 11-24.pdf

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ENGINE 1-11

Compare the measured values to deter-mine the amount of clearance.

If the clearance is beyond the standard

value for assembly. replace either of the

pistons or the cylinder liners with higher

rate of wear.

FIG. 1-31

(2) Inspection of pistons

1) Check the pistons visually for wear. cracking

or scuffing. paying particular attention to the

ring grooves. Replace the pistons if found to

be cracked or heavily scuffed.2) Measurement of piston clearance.

1. With an outside micrometer, measure the

diameter of the piston at a point 52 mm

below the piston head in direction at a

right angle to the piston pin hole (piston

grading position).~ L ~~[;;~;:."..",':;-i.-:~": .-

FIG.1-33

.If~[~

Measurement of clearance between piston

and liner with feeler gauge.

Insert a 0.10 0.12 mm feeler gauge into the

clearance between the cylinder wall and

thrust face of piston. Force the piston

against the cylinder wall in direction oppo-

site to the feeler gauge and pull the gauge

vertically with a pull scale.

The clearance is correct if the pull required

to move the feeler gauge is within 0.5 -1.0

kg.

~ -,..cc;;.,".~;

c".c

~",c

FIG. 1-32

2. With a cylinder bare indicatar measure

the cylinder liner bare. diameter at the

lawer partian or upper partian where the

liner w ali is kept intact af the pistan rings.FIG. 1-34

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1-12 ENGINE

Inspection of piston rings

Piston rings ShoUld be replaced with new oneS

whenever the engine is overhauled. When in-

stalling new piston rings. the f0110wing points

ShoUld be checked.

1) Inspection of piston ring gaps.

Insert the piston ring into the cylinder liner

bore. Pu.sh the piston ali the way into the por-

tion where the amount of wear is generally

smallest 9vith the piSton head, So that it is

held at a right angle to the cylinder liner wall.

Measur.e the ring gap with a feeler gauge and

replace the piston ring with a new one if the

measured value is beyond the limit. FIG. 1-35

OIL CONTROL RINGST, 2ND, 3RD COMPRESSION RING

IN CYLlNDERN CYLlNDERFREE

(REFERENCE)

about 12.00.2 -0.4

1.5

FREE

(REFERENCE)

about 12.5 Q.1 Q.3

1.5

Standard value for assembly (mm)

Limit far use (mm)

2) Inspection of clearance between piston ring

and groove.

An excessive piston ring clearance can

cause loss of compression and oil burning

whiJe an insufficient clearance may invite

sticking. Measure the clearance between the

ring and ring groove in the piston with afeeJer gauge. Take measurement at se\/eral

portions around the circumference of the

piston.

FIG. 1~36

Inspection of piston pins

1) Inspection of piston pjns for wear.

Measure the outside diameter of the piston

pins with an outside micrometer. Replace the

piston pin if the measured value is beyond

the limit.

FIG. 1-37

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ENGINE 1-1::

1. When the ccnnecting-rcd is assembled t c

the crankshatt, check the clearance be-

tween the ccnnecting-rcd big-end and

side tace ct the crankpin using a teeler

gauge.

2) Fitting interference between piston pin and

piston.The pjston pin fjtting jnterference is normaf

when piston pin can be press-fitted into the

pjston with a good fìnger pressure after heat-

ing the piston to 60°C or so wi.th a piston

.heater.

Fittin9 interference between piston

pin a~1dpiston (mm)

-..0.004- 0.011

(5) "Inspectio~ of connecting-rods -

1) Inspection of connecting-rods for distortjon.

Check the connecting-rod for distortion or

misalignment between the small-end and

big-end using a connecting-rod aligner.

Correct or replace the connecting-rod with a

new one if the amount of distortion or mis-

alignment is beyond the value indicating

need for servicing.

FIG. 1-39

3) Inspection of clearance between piston pin

and connecting-rod small-end bushing.

The clearance between the piston pin and

connecting-rod small-end bushing is normalwhen the connecting-rod turns about the pis-

ton pin smoothly as tested by holding the pis-

ton pin with hand.

NOTE: When checking the connecting-rod for dis-tortion or misarignment with connecting-rod

aligners. check to be certain the small-end

bushing and big-end bearing are free from

wear. or false indication of aligners will

result.

I Il

\

\~

~

FIG. 1-38

2) Inspection cf connecting-rad big-end and

small-end far wear. FIG. 1-40

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4) Replacement ct ccnnecting-rod small-end

bushing.When a new bushing is installed. tinish the

inner tace with a reamer.

Inside-diameter of bushing after

reaming (atter installation on

connecting-rod) (mm)

27.008- 27.015

FIG -42Reassembly..of pistons and connecting-rods1 ' Heat the piston to about 60°C using a piston

heater and install the piston pjn by aligningthe connectjng-rod small-end bushing wjth

the piston pin hole.NOTE: Install the connectjng-rod, so that its

side with the cyljnder number mark

is turned toward the combustion

chamber .

L.:'"; FIG. 1-43

4) When the piston rings are installed apply en-

gine oil to the entire piston rings, then checkthat the piston rings turn smoothly within the

grooves without binding.5) Measure the weight of each piston and

connecting-rod assembly and compare themeasured values to make certain variance in

weight of piston and connecting-rod assem-

bly is within the specified range.

Crankshaft, bearing and flywheel-3

FIG. 1-4

~

~ ;..s~ frtJ

'Z'7' 32

\,{i'\I 7 S 910 ~ CP \ G' CP CP Il 11

.~ .

.,!o .

;I?.. (~~. ; ...~

~~~.

~--~__~_~_3

(""'l

-l).\.'::

~.1

::o:~

2) Install the snap ring on each end of the pis-

ton p.in.3) Assemble the piston rings to thè piston.

NOTE: 1. Assemble the compression ringsand oil control ring to the piston

with the NPR mark sides up.2. To assemble the oil control ring.

proceed as follows:Assemble the coil spring expan-der into the ring groove and posi-tion the oil control ring over thecoil spring expander. so that the

coil spring expander gap and oil

control ring gap are positioned

180degrees apart.

FIG. 1-44

1. CRANKSHAFT BeARING KIT 9. CRANKSHAFT GEAR2. THRUST BEARING 10. FEATHER Key

3. CRANKSHAFT 11. PIN4. BOL T 12. CRANKSHAFT PILOT BEAR ING

5. WASHER 13. RING GEAR6. CRANKSHAFT PULLEY 14. FL YWHEEL7. THROWeR; OUST SEAL 15. BOL T

8. OIL THROWeR 16. WASHeR

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ENGINE 1-15

Service t 0015: Micrameter, cylinder bare indicatar

ar plastigauge, crankshaft aligner

ar V-black.s, dial indicatar, feeler

gauge, d~e penetrant flaw detectar.

NOTE: Measure the outside diameter of

the crankshaft journals and

crankpins at the positions I and Il

in directions A and e.

Special tools: Crankshaft pilot bearing remover

19-8523-1812-0)..

FIG

FIG.

(1) Inspection of crankshaft1) Inspection of crankshaft for cracking and

damage.1. Check the entire crankshaft visually for

damage paying particular attention to the

portions supported by the bearings. If

heavy scores are noticeable. have the

crankshaft ground and install undersize

bearings. (Refer to paragraph 4) crank-

shaft grinding on page 1-17).

2. Check the crankshaft for cracking using

dye penetrant flaw detector or a magnetic

flaw detector as needed. Replace the

crankshaft with a new one if any crackingis noticeable.

2) Inspection of crankshaft for wear.

With an outside micrometer, measure the

outsjde diameter of the crankshaft journals

and crankpins to estimate the condition of

wear.

1. If the amount of unèven wear in the

crankshaft journals or crankpins is

beyond the value indicating need for ser-

vicing. have the crankshaft ground and

install undersize bearings.

Replace the crankshaft with a new one if

the amount of uneven wear is such thatcrankshaft journals and crankpin diame-

ters can not be held within the limit for

use after grinding finish.

3) In5pection of crank5haft for run-out.

Support the Crank5haft on Crank5haft afign-

er5 or on V-block5 at it5 end5 and hofd the

probe of a dial indicator in contact with the

Crank5haft No.3 journaf. Carefully turn the

Crank5haft 1 full turn and take the reading of

the diaf indicator.

If the amount of the Crank5haft run-out j5

beyond the value indicating need for 5ervic-

ing. replace or correct the crank5haft u5ing a

bench pre55 without appfying heat.

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a. Install the crankshaft main bearing on

the cylinder body.Install the bearing cap and tighten the

cap bolts to specjfication and measure

the inside diameter of the bearing witha cylinder bore indicator.

FIG. 1-47

FIG. 1-48

b. Install the bearing on the connecting-rod big-end. Install the bearing cap and

tighten the cap bolts to specificationand measure the inside diameter of the

bearing with a cylinder bore indicator.

c. Compare the values obtained by

measuring the inside diameter of thebearing and crankshaft diameter to de-

termine the amount of oil clearance.

of crankshaft main bearings and

connecting-rod bearings

1) Visual inspection.

Check the crankshaft main bearings and

connecting-rod bearings visuaffy for poor

contact. separation and damage. Replace

the bearing if any abnormal condition is

noticeable.

2). fnspection of bearing tension and bearing

crush.

If ten5ion of the bearing is insufficient or if

bearing cru5h is exce5sive, it will prevent un-

iform contact between the bearing and cap

or between the bearing and cylinder body

and cau5e5 scuffing or bearing seizure.

1. 8earing tension.

Check to 5ee if the bearing has enough

tension, 50 that a good finger pressure is

needed to fit the bearing into position.2. Main bearing and connecting-rod bearing

tensjon.

As5emble the bearing to the cylinder

body, connecting-rod and bearing cap.

Pre5S the bearing against the bearing cap

{or cylinder body) and check that the bear-

ing has a tension.

If the bearing tension is insufficient. re-

pface the bearing with a new one.

3) Inspection of oil clearance between crank-

5haft and bearings.

One of the foflowing methods may be used to

measure the bearing oil clearance.1. Measurement of oil clearance with cylin-

der bore indicator.

7/27/2019 SEZIONE 1 PAG. 11-24.pdf


ENGINE 1-17

2 When having the crankshaft ground

.and installing undersize bearings.

measure the inside diameter of the

bearings to determine the diameter of

the crankshaft to be obtained after

grinding.

..

l.4

Measurement of oil clearance of oil

plastigauge.a. Wipe the crankshaft journafs and inner

face of the bearing clean to remove afl

traces of oil. :

b. Piace a plastigauge over the crankshaft

or bearing at the position away from theoil port in direction in line with the axis

of the crankshaft.

c. Instafl the crankshaft bearing cap or

.connecting-rod bearing cap and

tighten the bearing cap bolts to

-specification.NOTE: Do not turn the crankshaft of

connecting-rod with plasti-

gauge set in positi.on.

~,,~

d. Remove the bearing cap and flattened

plastigauge from the crankshaft or the

bearing. Check the width of flattened

plastigauge against the scale printed

on the container. If the oil cfearance is

beyond the value indicating need for

servicing, replace the bearings with

new ones.

i;~I~~,~ ""~..~c.;'j..;:;l;". -

FIG. 1-50

e. Follow the same steps to measure the

oil clearance between the crankpin and

bearing.

crankshaft

dimensionsground the followingo) Crankshaft grinding.

When using the under-size bearing. have the

NOTE: 1. Have the crankshaft ground. so that the curvature at

the fillets of the journals and pins is maintained at the

radius 3.3-3.7 mm.

2. Surface coarseness of both the journals and pins

should be held within 0.001 mm.

3. Run-out of journals and pins should be held within

0.007 mm.

5) Removal and inspection of pilot bearing.Remove the pilot bearing using special tool ;

remover (9-8523-1812-0) and then check thepilot bearing for abnormal noise or un-smooth rotation by rotating it with hand. Re-

piace the bearing if found to be defective.

7/27/2019 SEZIONE 1 PAG. 11-24.pdf


Cylinder head assembly3) Inspection of flywheel

1) Inspection of flywheel for wear.

Measure the depth (t) from the clutch cover

fitting face to the friction face. If the meas-

ured value is beyond the limit. rep(ace the

flywheel. )

3-4

INSPECTION

ITEMENGINE

MOOEL

LlMIT FOR USE

624Q Depth (t)

STANDARD

V ALUE FOR

ASSEMBLY

17.9-18.1 19.0 or more

'23

13. HEAO COVER14. OIL FILLER CAP

15. NIPPLE16. VALVE COLLET17. SPRING SEAT1S. SEARING RING19. VALVE SPRING; OUTER20. VALVE SPRING; INNER

21. EXHAUSTVALVE22. INLET VALVE23. LOWER SeAT AOOITION

1. CYLINDER HEAD ASSEMBL Y

2. HOT PLUG3. CYLINOER HEAD GASKET

4. SEALING CAP5. CYLINDE R HEAD BOL T

6. SEALING CAP

7. VALVE SEALB. VAL\lE GUIDE; INLeT

i. VALVE GUIDE; EXHAUST10. VAL\lE SEAT INSERT; EXHAUST

1'. vALve seAT INSERT; lNLeT

12. HeAD COVER aAsKET

FIG. 1-53

Service tools: Vernier caliper5, micrometer, cylinder

bore indicator, 5quare, feeler gauge,

strajght edge, valve spring tester, oil

stone, valve refacer, valve 5eat cutter

valve lapper .

Special tools: Valve 5pring COmpre550r(9-8523-1423-0), valve gujde remover

and jnstaller (9-8523-1212-0).

(1) Disassembly of cylinder head assembly1) Removal of valves and valve spririg.

Set special tool; valve spring compressor(9-8523-1423-0) with bolts using rocker arm

bracket bolt holes and compress the valve

springs. Remove the va(ve collets. valve

spring seat. valve springs and valve.

REFERENCE: If the valv~ collets are stuck

and do not come out. apply a

shock to the valve with a mal-

let. Fasten a tag bearing cY-linder number to the valves

from each cylinder to preventinterchanging.

FIG. 1-52

2) Inspection of flywheel for cracking.

Examine the entire flywheel carefully for heat

cracking.

and replacement of flywheel

ring gear1) Check the ring gear teeth for wear or chip-

ping and replace the ring gear as necessary.

2) Ring gear removal.

Remove the ring gear from the flywheel by

tapping around the side face of the gear with

a brass rod and a hammer after expandingwith a gas burner.

3) Ring gear installation (thermal-fitting).

Heat the entire ring gear evenly with a gas

burner to invite expansion and install the

gear on the flywheel. The ring gear should be

installed, so that its face with heavy chamfer-

ing on the outer cjrcumference (gear) is

turned to the crankshaft side.

An improvised means of thermal-fitting the

ring gear to the flywheel consists of the

following.The ring gear can be brought to expansion

by setting fire to oil-soaked rag wound spiral-

Iy around the entire ring gear.

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ENGINE 1-19

~

If the amount of distortion is in excess of 0.2

mm, Correct with a surface grinder. Replace

the cylinder head assembly if the amount of

distortion is_beyond 0.4 mm.

NOTE: If the cylinder head has been ground.Correct the valve seat inserts. So that

the amount of valve seat depression

is adjusted to 0.7 mm. :

; (Refer to paragraph {5) "Inspection

of valve sea,t inserts'.).

FIG. 1-54

3) In5pection of manifold fitting face of cylinder

head for di5tortion.

Check the intake and eXhau5t manifold fit-

ting face of the cylinder head for di5tortion

u5ing a 5traight edge and a feeler gauge and

correct with a 5urface grinder a5 nece5sary.

(2) In5pection 01 correction 01 cylinder head5

1) Inspectjon of cylinder heads for cracking and

damage.Remove any carbon from the lower face of

the cylinder heads carefully to prevent

scratching of the valve seat faces. Examine

the entire cylinder heads for cracking and

damage using a dye penetrant flaw detector

as needed.

2) Inspection of cylinder head lower face for

distortion.

Hold a straight edge against the lower face of

the cylinder head and check the clearance

between the straight edge and cylinder head

lower face with a feeler gauge.

NOTE: 1. Take measurement in 6

directions.

2. Use a straight edge which is long

enough to cover the entire length

of the cylinder heads in ali direc-

tion of measurement.

4) Hydraulic test.

Cfean the water passages and water jets with

compressed air and check them for restric~

tions. Perform a hydraulic test on the cyljn~

der head for 5 minutes using pressurized

water of 3 kg/cm2.

(3) Inspection and correction of combustion

chambers

1) Inspectjon of hot plugs for depression.

1. Clean the lower face of the cylinder head

with care not to scratch the hot plugs.

2. Position a straight edge across the hot

plugs and check the amount of depres-

sion of the hot plugs using a feeler gauge.

If the measured value js beyond the

specified range, replace the hot plug.

FIG. 1-55

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1-20 ENGINE

4) Installation of hot pJugs.

Install the hot plugs in position by aligning

the ball with the locating groove in the cylin-

der head usjng a mallet or a copper hammer.

NOTE: Hot plugs have been machined after

installatjon on the cylinder head.Make certain the hot plugs are in-

stall~d on their originaJ positions..,

FIG. 1-57

2) Removal of hot plugs and heat shields.1. Insert a bar (3-5 mm in diameter) into the

.injection nozzle hole in the cyHnder head

and tap out the hot plug downward using

a hammer.NOTE: Apply cyl~nder number mark to

the hot plugs with a marking pen

to prevent interchanging.

5) Replacement of hot plugs.1. Wt'en installing a new hot plug. proceed

as f0110WS: nstall the hot plug by aligningthe ball with the 10cating groove on thecylinder head. then drive it in with a mallet

just enough, So that it is settled in position

of jnstallation..6

Fitting interference between hot plug

and cylinder head (mm)0.001 -0.051

14.4 2. Position a piece of protective metal with a

smooth surface over the hot plug and

press it further in by applying a load of

4500-5500 kg with a bench press.

NOTE: Avoid using excess load.IG. 1-58

2. When the hot plug is removed, remove the

heat shield upward by tapping on the

lower face of the heat shield..3) Inspection of combustion chambers.

Remove carbon from the combustion cham-

bers using care not to scratch the hot plug

fitting face of the cylinder head, then check

the inner face of the combustion chambers.

glow plug holes. hot plug fitting face and hot

plugs for damage. Replace the cylinder head

if found to be cracked or damaged. When

checking the combustion chambers, pay par-

ticular attention to the hot plug fitting face as

burrs or high spots on this face will prevent a

positive contact between the hot plug and

cylinder head causing depression or jumpingof hot plug. FIG. 1-60

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ENGINE 1-21

Inlet valve

diameter

'side8.00 7.88

Exhaust valve outside

diameter

8.00 7.85

3. When the hot plug is installed, finish the

face of the hot plug with a surface grinder

to gain matching with a cylinder head.

4. Test for depression or projection by tap-

ping lightly with .a mallet.

6) Installation of heai shield.

Install the heat shield with the flanged side

up on the cylinder head by tapping on the

flange lightly with a brass bar.

NOTE: Discard used heat shield and insta(1 a

new one at reassembly.

2. Inspec~ion of valve head and thickness.

Check ~he seating face of the valve head

for scoring or step we.ar-and correct with a

ya:Jve refacer as necessary.

Measure the thickness of the valve head.

Replace the valve if mèasured valve is less

than 1.0 mm.

FIG -63

2 Inspection and replacement of valve guides.

1. Inspection of valve guide inner wall for

wear.

Insert the valve stem into the valve guide

and check for looseness to estimate the

amount of wear in the valve guide inner

wall.

If the amount of clearance between the

valve stem and valve guide is beyond thevalue indicating need for servicing. re-

pIace the valve guide together with the

valve.

(4) Inspection and correction of valves and valve

guides1) Inspection of valves.

1. Inspection of valve stem for wear .

With an outside micrometer measure the

diameter of the valve stem at the upper,

center and lower portions. If the mea-

sured values are beyond the limit. replace

the vafve together with the valve guide.

Slight steps on the valve stem end may be

removed with an oil stone orvalve refacer.

7/27/2019 SEZIONE 1 PAG. 11-24.pdf


1-22 ENGINE

3) Removal of vaJve guides.

To remove the intake or exhaust valve guide.

proceed as follows: Position the cylinder

head with the lower f~ce up and drive out the

valve guide using speciaf tool; remover and

installer (9-8523-1212-0) and a hammer.

\

\

\

.//

,-

FIG. 1-67

5) Jnstallaticn cf valve guide cil seals"

Drive the cil seal intc the intake valve guide;'c",:;"; .:@,fiti:" ..::-.::'i:.."-;:'~\~~:;V~11!~IG. 1-65

~,~!?

.'..G~i

';~~~~1;

'.\.;'.~y~

:~~:~;,~'i'~~f

~~~~

4) Installation of vafve guides.

To install the valve guide, proceed as fol-

I 19W5: Position the cylinder head with the

lower face down on a suitable support and

set the adapter to the special tool; remover

and installer (9-8523-1212-0), then install the

valve guide using a hammer.

NOTE: Apply engine oil to the outer circum-

ference of the valve guide before

installation.

FIG. 1-68

(5) Inspectjon and rep'acement of va've seat

insertsExcessive wear in the valve seat insert will pre-

vent normal contact between the valve and seat

resulting poor engine performance. Check the

width of contact and amount of depression of

the valve seat inserts. If the measured values are

beyond the value indicating need for servicing.

replace the valve seat inserts with new ones.1) 'nspectjon of valve seat i.nserts for wear .

Since it is impracticable to check the amount

of wear in the valve seat inserts as fitted in

position of installation. install a new valve

into the valve seat insert and check the

amount of depression of the valve head from

the cylinder head lower face to estimate the

amount of wear in the valve seat insert.

Replace the valve seat insert if the measured

value js beyond the value indicating need for

servicing.IG. 1-66

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ENGINE 1-23

FIG. 1-69

2) Inspectian af valve seat cantact width.

If the valve seat cantact width is beyand thevalue indicating need far servicing. carrect

with a valve seat cutter.

VALUE INDICATING

NE ED FOR

SERVICING

INSPECTION

ITEM

STANDARD VALVE

FOR ASSEMBL y

3) Replacement of valve seat inserts.

1. Removal.

With an electric welder, give welding

beads to opposed two (2) portions of the

inner face of the vaJve seat insert. Then

alJow the cylinder head to cool off from 3

to 5 minutes, so that contraction of the

valve seat insert takes pIace, permitting

removal with a screwdriver.

.2. Inspection of fitting interference between

valve seat insert and cylinder head.

..Clean the valve seat insert bore to remove

.-carbon and oxidized deposits. Measure

the inside diameter of the valve seat insert

bore and outside diameter of a new valve

seat insert to be installed and compare

the measured values to determine the

amount of fitting interference. If the

amount of fitting interference is less than

0.06 mm, correct the valve seat insert bore

by means of welding excess metal and

machining.3. Installation.

Press a new valve seat insert into the bore

using a bench press. When the valve seat

insert is installed, check the amount of

depression of the valve from the lower

face of the cylinder head. If the amount of

depression of the valve is less than 0.7

mm, correct with a valve seat cutter.

4. Inspection and correction of valve seats.

Apply thin coat of Special compound (red

lead and oil mixture) to the seating face of

the valve evenly and bring the valve into

light contact with the seat to get an im-

pression of valve seat contact. Check and

see if the contact width is within the stan-

dard value for assembly given under

paragraph 2) "Inspection of valve seat

contact width" and is wef( centered on the

valve seat.

FIG. 1-70

/

1500

-~--.;~~-=~=:: ~

:r::=:::t---

~~

'l-'

FIG -72IG. 1-71

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1-24 ENGINE

If the impression of contact or contact

width is abnormal. correct with a valve

seat cutter and Ia.p the valve seat using

fine lapping compound and valve lapper.

(6) Inspection of valve springs

1) Check the valve springs visually fo_r damage.

!,.~~~~~;~~~

,,~~;;:;#~,,~

1_ut

't\o..',',,'

;:;"'~"

if~i~~~

~~

~~.

._~""..,!i-irl~

~:;ii::1j;;~'fi~~.,.-' "",::;;;,:~~~1i

il~ii

I~~

.!:::~:~

FIG -73

2) Check spring tension and free length of the

valve springs with a valve spring tester and

replace if measured value is beyond the limit.

3) Inspection of valve springs for inclination.

Hold the valve spring on a surface plate in

upright position and measure the amount of

inclination of the valve spring. If the amountof incfination is beyond the fimit, replace the

valve spring.FIG

STANDARD VALUE

FaR ASSEMBL y

NOMINAL

DtMENSIONLlMIT FOR USEINSPECTION ITEM

When compressed

to fitting length of

39mm

Outer

spring

15.718.5 17.5 19.5

Spring

tension (kg) When compressed

to fitting length of

37mm

Inner

spring7.05.8 8.8.3

Outer

spring

44.56.0

Free length (mm)

Inner

spring

41.542.9

Outer and

inner spring1.0

Incfination from vertical (mm)

3) In~tall the valve springs and valve spring seat

and set special tool: valve spring compressor(9-8523-1423-0) to the rocker arm bracket

bolt holes. then compress the valve spring

and install the valve collets.

(7) Reassembly of cylinder head assembly

1) Apply clean engine ojl to the valve stem be-

fore jnstalling the valve into the valve guide.

2) Position a suitable support under the cylin-

der head to prevent lowering of the valves.

Documents

SEZIONE 1 PAG. 11-24.pdf