Defender (1993+). Manual — part 22

ENGINE

Examine connecting rods

20. Check alignment of connecting rod.
21. Check connecting rod small end, piston pin

must be a press fit.

Check crankshaft bearings

22. Locate bearing upper shell into the connecting

rod.

23.

Locate connecting rod and bearing

onto its

NOTE: Domed shape boss on connecting
rod must face towards front of engine

on

right hand bank of cylinders and towards

rear on left hand bank.

24.

When both connecting rods are fitted, bosses

30. Remove connecting rod cap and shell.

will

face inwards towards each other.

31.

Using scale printed on Plastigauge packet,
measure flattened Plastigauge at its widest
point.

32.

The graduation most closely corresponding

to

width

of

Plastigauge indicates bearing

clearance.

33. Correct bearing clearance with new or

overhauled components is 0.015

to

0.055

mm.

34. If a bearing has been in service,

fit

a new

bearing

if

clearance exceeds

0.08

mm.

35.

If a new bearing is being fitted, use selective

assembly

to

obtain correct clearance.

36. Wipe

off Plastigauge with an oily rag. DO

NOT scrape

it

off.

NOTE: It is important that connecting rods,
caps and bearing shells be retained

in

sets, and in correct sequence.

ST822M

Assembling pistons to connecting rods

25.

Place a piece of Plastigauge (P61) across

centre of lower half of crankshaft journal.

37. Using tool LRT-12-013 refit each piston

to

its

26.

Locate bearing lower shell into connecting rod

connecting rod as follows:

cap.

27. Locate cap and shell onto connecting rod.

a.

Clamp hexagon body of LRT-12-013

in a vice, with adaptor LRT-12-014

NOTE: Note that rib

on

edge

of cap must

positioned as instruction 7d.

be o n same side as domed shape

boss on

Remove large nut of LRT-12-013 and

connecting rod.

push the centre screw approximately
50 mm into body until shoulder is

28. Secure connecting rod cap. Tighten

to

50 Nm.

exposed.

29.

Do

not rotate crankshaft while Plastigauge is

C.

Slide parallel guide sleeve, grooved

end last, onto centre screw and up

to

shoulder.

b.

in use.

crankshaft journal.

ENGINE

k

d.

Lubricate piston pin and bores

of

j.

Set a torque spanner

to 16

Nm. This

connecting rod and piston with

represents minimum load for an

graphited oil (Molykote 2). Also

acceptable interference

fit

of

piston

lubricate ball race and centre screw

pin in connecting rod.

of

LRT-12-013.

k.

Using torque spanner and socket

on

Fit connecting rod and piston together

large nut, and holding lock screw, pull

onto tool, with markings aligned

if

piston

pin

in

until

flange

of

fitting original pair, with connecting

remover/replacer bush is 4mm

'B'

rod around sleeve up

to groove.

from face

of piston. This flange must

f.

Fit piston pin into piston bore, up to

not be allowed

to

contact piston.

connecting rod.

g.

Fit remover/replacer bush LRT-12-015

CAUTION: If torque spanner has

with its flanged end towards piston

not reached at least

16

Nm.

pin.

throughout pull, fit of piston pin to

h.

Screw stop nut onto centre screw and

connecting rod

is not acceptable

adjust nut

to

obtain an

0.8

mm end

and

necessitates

fitting

new

float

'A'

on whole assembly, and lock

components. The large nut and

nut securely with screw.

centre screw

of tool must be kept

body and screw large nut up to thrust
race.

e.

I.

Slide assembly back into hexagon

well oiled.

38.

Remove tool and check that piston moves

freely on piston pin and that no damage has

occurred during pressing.

k

h

ST778M

REMOVE AND OVERHAUL CRANKSHAFT

1.

Remove main bearing caps and lower bearing

shells.

Retain

in pairs and mark

with

number

of journal

until it

is decided

if

bearing shells

2.

Lift

out crankshaft and rear oil seal.

ST824M

are to be refitted.

ENGINE

Inspect and overhaul crankshaft

9.

The centre main bearing shell, which controls
crankshaft thrust, has thrust faces increased

3.

To check for straightness, place crankshaft on

in

thickness when more than 0.25 mm

vee-blocks at numbers one and five main

undersize, as shown in following chart.

bearing journals.

10. When a crankshaft is to be reground, thrust

4.

Using a dial indicator, check run-out at centre

faces on either side of centre main journal

main bearing journal.

must be

machined

in accordance with

dimensions in charts

that follow.

Main bearing journal size Thrust face width

Standard

Standard

0.25 mm undersize

Standard

0.50

mm undersize

0.25

mm oversize

11.

For example: If

fitting a

0.50

mm undersize

bearing, 0.125 mm must be machined

off

each thrust face

of centre journal, maintaining

correct radius.

Crankshaft dimensions

12. Radius for all journals except rear main

bearing

is

1.90

to 2.28 mm.

13. Radius for rear main bearing journal is

3.04

mm.

5. Total run-out at each journal should not

14. Main bearing journal diameter, see following

chart.

exceed

0.08

mm.

6.

If crankshaft is bent it is not suitable for

15. Thrust face width, and connecting rod journal

regrinding and should

be renewed.

diameter,

see

following chart.

7.

Check each crankshaft journal for ovality. If
ovality exceeds 0.040 mm around crankshaft

journal, regrind or

fit

a

new crankshaft.

8.

Crankshaft main and connecting rod bearings
are available in following undersizes:

0.25mm
0.50mm

ST826M

RR1793E

13