Content .. 102 103 104 105 ..

Defender 90 / 110 / 130. Manual - part 104

STEERING

Tap the splined end

of the spindle shaft to free the

bearing.

16. Withdraw the bearing cup and caged ball bearing

17. Withdraw the valve and worm assembly.
18. Do not disturb the trim screw, otherwise the

calibration will be adversely affected.

19. Withdraw the inner bearing ball race and shims.

Retain the shims.

6. Slacken the grub screw retaining the rack pad

Remove the rack pad adjuster.

Remove the sector shaft adjuster locknut.

Remove the sector shaft cover fixings.

assembly.

adjuster.

10. Screw in the sector shaft adjuster until the cover is

removed.

11. Slide out the sector shaft.

Steering

box

seals

20. Remove the circlip and seals from the

shaft

housing bore.

NOTE: Do not remove the sector bush unless
replacement

is required. Refer to instruction 23.

21. Remove the circlip and seals from the input shaft

housing bore.

NOTE: Do not remove the input shaft needle
bearing unless replacement is required.

12. Withdraw the piston, using a suitable

UNC

bolt

13.

Remove the worm adjusting screw locknut using

14.

Remove the worm adjusting screw using peg

screwed into

the tapped hole in the piston.

‘C’

spanner

606600.

spanner

606601.

continued

STEERING

Sector shaft assembly

27. Check that there is

no side play on t h e rollers.

28. If excessive side play on the roller does exist renew

29. Check the condition of the adjuster screw threads.
30. Examine the bearing areas on the shaft for

31.

the gear teeth for

or excessive

the sector shaft.

excessive wear.

wear:

Inspecting

22. Discard all rubber seals and provide replacements.

NOTE: A rubber seal is fitted behind the plastic
ring

on the rack piston. Discard the seal also the

plastic ring and provide replacements.

Sector shaft cover assembly

32. The cover, bush and seat are supplied as a

Steering box casing

If necessary, replace the sector shaft bush, using

suitable tubing as a drift.

wear.

replacement is necessary this can be undertaken by
using a suitable tap.

24. Examine the piston bore for traces of scoring and

Examine the inlet tube seat for damage.

33. The locknut functions also as a fluid seal and must

be replaced at overhaul.

26. Examine the feed tube

for signs o f cracking.

continued

STEERING

. . .

Valve and worm assembly

34. Examine the valve rings which must be free from

cuts, scratches and grooves. The valve rings should
be a loose

fit

the valve grooves.

35.

Remove the damaged rings ensuring that no

damage

is done to the seal grooves.

36. If required,

fit replacement rings, using the ring

expander 606602. Both rings and tool may be
warmed

found necessary. Use hot water for this

purpose. Then insert into the ring compressor
606603 to cool.

NOTE: Any sign of wear at locations

and 41

make it essential that the complete valve and worm

assembly are renewed.

Ball bearing and cage

blies

42. Examine the ball races and cups for wear and

43. If the ball cage has worn against the bearing cup, fit

44. Bearing balls must be retained by the cage.
45. Bearings and cage repair are carried out by the

complete. replacement of the bearings and cage
assembly. The bearing cup may be replaced
separately

only.

46.

remove the inner bearing cup and

shim

washers, jar the steering box

on the work bench.

general condition.

replacements.

NOTE: The expander will not pass over rings
already fitted. These rings must be discarded

allow access then renewed.

NOTE:  Should  difficulty  be  experienced  at  this
stage,  warm  the  casing  and  the  bearing  assembly.
Cool  the  bearing cup using a suitable mandrel and

jar the steering box on the bench.

37. Examine the bearing areas for wear. The areas

must be smooth and not indented.

38. Examine the worm track which must be smooth

and not indented.

39. Check for excessive end-float between the worm

and valve sleeve. End-float must not exceed

(0.005 in).

40. Rotary movement between the components at the

trim pin

is permissible.

41. Check for wear on the torsion bar assembly pins;

n o free movement should exist between the input
shaft and the worm.

Rack thrust pad and adjuster

47. Examine the thrust pad for scores.
48. Examine the adjuster for wear

the pad seat.

49. Examine the nylon pad and adjuster grub screw

assembly for wear.

continued

STEERING

Rack and piston

50. Examine for excessive wear

the rack teeth.

51.

Ensure the thrust pad bearing surface is free of
scores and wear.

52.

Ensure that t h e piston outer diameters are free
from burrs and damage.

53. Examine the seal and ring groove for scores and

damage.

54.

Fit

a new rubber ring to the piston. Warm the white

nylon seal and fit this to the piston. Slide the piston
assembly into the cylinder with the rack tube

outwards. Allow to cool.

REASSEMBLE

NOTE: When fitting replacement oil seals, these must

lubricated with recommended fluid. Also ensure that

absolute cleanliness

is observed during assembly.

Input shaft oil seal

56.

Fit the seal, lipped side first, into the housing.
When correctly seated, the seal backing will lie flat

on the bore shoulder.

57.

Fit the extrusion washer and secure with the circlip.

Input shaft needle bearing

55.

If necessary, replace the bearing. The replacement
must be fitted squarely in the bore (numbered face

of the bearing uppermost). Then, carefully push
the bearing in until it is flush with the top

of the

housing bore, Ideally, the bearing will be just clear
of the bottom of the housing bore.

Sector shaft seal

58.

Fit the oil seal, lipped side first.

59.

Fit the extrusion washer.
Fit the dirt seal, lipped side last.

61. Fit the circlip.

continued

Content .. 102 103 104 105 ..