Service manual

ManualsBrandsWesterbeke ManualsAutomotive120D-TWO

CAMSHAFT

I

PISTONS

AND

CONNECTING

RODS

Inspecting

The

Camshaft

Make

a

thorough

inspection of

the

injection

pump

and

the

valve

camshafts.

Check

the

Oldham's coupling,

each

ball

bear-

ing

and

the

cam

lobes

for

wear.

Also check

the

push

rods

and

tappets.

Check

ball

bearings

for

wear

and

noise.

Check

for

cam

lobe

-for

wear

and

damage.

Inspect

Oldham's

Coupling

for

wear.

TAPPET

Check

for

cam

contact

and

surface

wear.

Injection

Pump

Camshaft

Cam

Lobe

Height

Standard

30mm

(1.18in)

Limit

0.7mm

(0.027in)

Valve

Camshaft

Lobe

Height

Standard

27.37mm

(1.078in)

Limit

1.0rtlm

(O.D39in)

r7t\

t..m:ASURING

CAM

HEIGHT

Installing

The

Camshafts/Gears

Coat

the

cam

lobes

and

bearings with oil

then

install

them

in

the

reverse

order

of removal.

Position

the

timing

marks

on

the

gears aligning

them

with

the

marks

on

the

idler

gear.

After installation

is

complete check

and

adjust

the

fuel

injection timing and valve clearances.

Remove

the

rings

from

each

pistorr

with

the

piston

ring

pliers.

Using

the

piston

setting tool,

pull

out

the

piston

pin

from

each

piston.

Protecting your eyes

with

safety glasses, disengage

and

with-

draw the

snap

rings. Although mechanics generally

press

out

(and sometimes hammer out) piston pins, these

practices

are

discouraged. Instead, time should be taken

to

heat

the

pistons,

either

with

a heat

gun

or

by

using a hot plate.

Pins

will

almost

fall

out of heated pistons.

While the piston

is

still

warm,

check for bore

integrity.

Insert

the

pin

from

each side.

If

the

pin

binds at the

center,

the

bore

might

be

tapered; if

the

bore

is

misaligned,

the

pin

will

click

or

bind

as

it enters

the

far boss.

NOTE:

The number stamped on the rod

shank

and cap should

correspond to the cylinder number. Sometimes these numbers

are scrambled

or

missing,

and

the mechanic must supply them.

Stamp the correct numbers on the

pads

provided and,

to

pre-

vent confusion, deface the originals.

CONNECTING

ROD

Inspect

for

end

play

or

twist.

Inspect

piston

for

wear,

seizure,

and

streaks.

Check

the

clearance

between

piston

and

cylinder.

Standarrl:

0.0027

•

0.0033/n

(0.07·

0.84mm)

PISTON

PIN

§

~:;~~n~;!ct

for

damage

and

wear.

PRESSING

OUT

PISTON

PIN

End

play

Standard:

0.0039-

0.0138/n

(0.1

-

0.35mm)

Inspect

lor

~

PISTON

wear

and

damage.

Inspect

ring

grooves

for

IDLER

GEAR/

(NOTE

TIMING

GEAR

MARKS

1 &

2)

-CRANKSHAFT

GEAR

PISTON

AND

CONNECTING

ROD

DISASSEMBLY

PISTON

Remove

the

oil

pan, gasket

and

the oil screen

strainer.

Chalk

the

cylinder number

on

the

side

face

of

the

big end of

each

connecting

rod

to

prevent confusing

the

connecting

rods.

Remove

the

connecting rod cap

from

each piston

and

rod

assembly

and

draw

the

assembly upward

from

the

cylinder.

Take

care

not

to

allow the connecting

rod

to

scratch

the

crank-

shaft

pin

and

cylinder.

Keep

the

removed

parts

(connecting

rod,

rod

cap,

piston,

etc.) classified

by

cylinders.

16

-

wear.

o I

BEARINGS-

PISTON

SETTING

TOOL

Check

tor

contact,

seiziJre,

flaking,

and

fusion.

Oil

Clearance

Standard:

0.00087

•

0.0020/n

{0.022-

o.osimm)