Defender (1993+). Manual — part 77

KEY TO PAS PUMP

1. Drive shaft and flange assembly.

12.

Valve housing.

2. Oil seal.

13. Magnet.

3 . Drive shaft bush.

14. Pump cover.

4.

Drive shaft key.

15. Pump cover ' O ' ring seal.

5.

Drive shaft housing.

16. Outlet pipe union pipe.

6. Inner spring ring.

17, Large 'O' ring.

7.

Vane.

18. Small 'O' ring.

9.

Outer spring ring.

20. Valve assembly.

10.

Locating dowels.

21. Pump assembly bolts (4

off).

11. Pump outer member.

8.

Vane rollers.

19. Spring

28

REISSUED: FEB

1993

STEERING

POWER STEERING FAULT

DIAGNOSIS

SYMPTOM

CAUSE

TEST ACTION

CURE

INSUFFICIENT POWER

(1)

Lack of fluid

Check hydraulic fluid tank level

If

low, fill and bleed the system

ASSISTANCE WHEN
PARKING

(2)

Engine idling speed too low

(4)

Defective hydraulic pump and/

or pressure relief valve

Try assistance at fast idle

(a) Fit pressure gauge between
high pressure hose and steering
pump. with steering held hard on

full

lock, see Note

1

below, and

Power steering pump test
(b) Release steering wheel and

allow engine to idle.

See

'Power

steering pump test.

self-centring action

This is caused by over-tightening

It

is

most important that this screw

the rocker shaft backlash adjusting is correctly adjusted See
screw on top

of

steering box.

instructions governing adjustment

Check for loose torsion bar fixings

Fit new valve and worm assembly

on steering

box

valve and worm

assembly.

Check by visual inspection, leaks

from

the high pressure pipe lines

are best found while holding the
steering on full lock with engine
running at fast idle speed (see
Note 1 below). Leaks from the
steering box tend to show

up

under

low pressure conditions, that is
engine idling and no pressure on
steering wheel.

Check the

loose

runs of the hoses. Alter hose route or insulate

as

necessary

If necessary. reset idle

speed.

Adjust the driving belt.
If

pressure is outside limits (high or

low) after checking items 1 and 3,
see Note

2

below

(3)

Driving belt slipping.

Check belt tension.

If

pressure is greater, check

steering box for freedom and

POOR HANDLING WHEN

VEHICLE

IS

IN MOTION

Lack

of

castor action

Steering too light and /or over
sensitive

HYDRAULIC FLUID LEAKS Damaged pipework, loose

connecting unions, etc

Tighten or renew as necessary

EXCESSIVE NOISE

(1)

If the high pressure hose is

allowed to come into contact with
the body shell, or any component

I

not

insulated by the body

mounting, noise will

be

transmitted

lo

the car interior.

(2)

Noise

from

hydraulic pump.

Excessive pressure due to faulty

relief valve in hydraulic pump

Check oil level and bleed system.

Check by visual inspection

If

no cure, change hydraulic pump.

Fit new steering box and rectify
hydraulic pump or replace as
necessary.

CRACKED STEERING

Note

1

Note

2

Never hold the steering wheel on full

lock

for more than 30 seconds in any one minute,

to

avoid causing the oil to

overheat and possible damage to the seals.

High pressure - In general it may

be

assumed that excessive pressure is due to a faulty relief valve in the hydraulic

pump.

Low pressure - Insufficient pressure may be caused by one

of

the following:

1

Low fluid level in reservoir

Most usual cause of

2.

Pump belt slip

insufficient pressure

3

4

5
6
7

Leaks in the power steering system
Faulty relief valve in the hydraulic pump
Fault in steering box valve and worm assembly
Leak at piston sealing in steering box
Worn components in either steering box or hydraulic pump

29

REISSUED: FEB

1993

STEERING

OVERHAUL DROP ARM BALL JOINT

The drop arm ball joint can be overhauled and there
is a repair kit available which consists of the
following items.

Ball

Pin

Ball lower socket

Retainer

Spring

Spring rings

'O' ring

Dust cover

Cover plate

Ball

top socket

Circlip

Dismantle

1

Remove the drop arm from the vehicle and

clean the exterior.

2.

Remove the spring rings and prise-off the dust

cover.

3. In the interests of safety, position the ball joint

under a press to relieve the spring tension
and support the housing both sides of the

ball

pin, as illustrated. Apply pressure to the cover
plate and remove the circlip and slowly
release the pressure.

WARNING: Personal injury could result

if the

circlip is removed without pressure being applied
and maintained to the cover plate.

4.

Remove the spring, top socket, and ' O ' ring.

30

REISSUED:

FEB 1993

STEERING

5.

Since the ball pin cannot be removed with the

6. Using

a

sharp-edged punch or chisel, drive

the ball lower socket from the housing. Should

difficulty be experienced, apply gentle heat to
the housing and then continue to drive the
socket from the housing.

7.

Clean the housing and remove any burrs.

retainer in position, tap the threaded end of
the ball pin to release the retainer and to
remove the pin from the housing.

Assemble

8. Press-in the lower socket squarely up to the

shoulder.

9.

Dip the ball in Duckhams LB 10 grease, or

equivalent and fit to the housing and pack
with grease.

10.

Fit the top socket.

11.

Fit the spring, small diameter towards the ball.

12.

Fit the ' O ' ring and using the same method as

for removing the circlip and compress the
cover plate and secure with the circlip. Ensure
that the circlip is fully seated in the machined
groove

.

13. Press the retainer on to the ball pin

so

that

the top edge is level with the edge of the
taper.

14. Fit the dust cover and retain with the two

spring rings.

15.

Fit the drop arm to the steering box using a
new lock washer. Tighten the retaining nut

to

the correct torque and bend over the lock
washer.

16. Assemble the ball pin to the drag link, see

instructions for fitting drag

link

and track rod,

and tighten the castle nut to the correct torque
and secure with a new split pin.

REISSUED:

FEB

1993

31