Reassemble
REASSEMBLE
NOTE: When fitting replacement oil seals, they must be lubricated with recommended fluid. Also ensure that absolute cleanliness is observed during assembly.
Input Shaft Oil Seal
Oil Seal:
53. Fit the seal, lipped side first, into the housing. When correctly seated, the seal backing will lie flat on the bore shoulder.
54. Fit the extrusion washer and secure with the circlip.
Sector Shaft Seal
Sector Shaft Seal:
55. Fit the oil seal, lipped side first.
56. Fit the extrusion washer.
57. Fit the dust seal, lipped side last.
58. Fit the circlip.
Fitting The Valve And Worm Assembly
Valve/Worm Assembly:
59. If removed, refit the original shim washer(s) and the inner bearing cap. Only Petroleum jelly may be used as an aid to assembling the bearings.
NOTE: If the original shims are not available, fit shim(s) of 0.76 mm (0.030 in) nominal thickness.
60. Fit the inner cage and bearings assembly.
61. Fit the valve and worm assembly, using seal saver RO1015 to protect the input shaft seal.
62. Fit the outer cage and bearings assembly.
63. Fit the outer bearing cup.
Worm Adjuster:
64. Fit a new worm adjuster sealing ring and loosely screw the adjuster into the casing. Fit the locknut, but do not tighten.
65. Turn in the worm adjuster until the end-float at the input is almost eliminated.
66. Measure and record the maximum rolling distance of the valve and worm assembly, using a spring balance and cord coiled around the torque setting tool RO1016.
67. Turn in the worm adjuster to increase the figure recorded in instruction 66 by 1.8-2.2 kg (4-5 lb) at 1.250 in (31.7 mm) radius to settle the bearings, then back off the worm adjuster until the figure recorded in instruction 66 is increased by 0.9-1.3 kg (2-3 lb.) only, with locknut tight. Use worm adjusting wrench LSTi19 and C wrench LSTi2O.
Fitting The Rack And Piston
Rack/Pinion:
68. Screw a slave bolt into the piston head for use as an assembly tool.
69. Fit the piston and rack assembly so that the piston is 63.5 mm (2.5 in) approximately from the outer end of the bore.
70. Feed in the sector shaft using seal saver 606604 aligning the center gear pitch on the rack with the center gear tooth on the sector shaft. Push in the sector shaft, and, at the same time rotate the input shaft about a small arc to allow the sector roller to engage the worm.
Fitting The Rack Adjuster
Rack Adjuster:
71. Fit the sealing ring to the rack adjuster.
72. Fit the rack adjuster and thrust pad to engage the rack. Back off a half turn on the adjuster.
73. Loosely fit the nylon pad and adjuster set screw assembly to engage the rack adjuster.
Fitting The Sector Shaft Cover
74. Fit the sealing ring to the cover.
75. Screw the cover assembly fully on to the sector shaft adjuster screw.
76. Position the cover on to the casing.
77. Tap the cover in place. If necessary back off on the sector shaft adjuster screw to allow the cover to joint fully with the casing.
NOTE: Before tightening the fasteners, rotate the input shaft about a small arc to ensure that the sector roller is free to move in the valve worm.
Sector Shaft Cover:
78. Fit the cover fasteners and tighten to 22-27 Nm (16-20 ft lbs).
Fitting The Cylinder Cover
Cylinder Cover:
79. Fit the square section seal to the cover.
80. Remove the slave bolt fitted at operation 68 and press the cover into the cylinder just sufficient to clear the retainer ring groove.
81. Fit the retainer ring to the groove with one end of the ring positioned 12 mm (0.5 in) approximately from the extractor hole.
Adjusting The Sector Shaft
Adjusting Sector Shaft:
82. Set the worm on center by rotating the input shaft half the total number of turns from either lock.
83. Rotate the sector shaft adjusting screw counter-clockwise to obtain backlash between the input shaft and the sector shaft.
84. Rotate the sector shaft adjusting screw clockwise until the backlash is just eliminated.
85. Measure and record the maximum rolling resistance at the input shaft, using a spring balance, cord and torque tool RO1016.
86. Hold the sector shaft adjuster screw and loosely fit a new locknut.
87. Turn in the sector shaft adjuster screw until the figure recorded in instruction 85 is increased by 0.9-1.3 kg (2-3 lb) with the locknut tightened.
Adjusting The Rack Adjuster
88. Turn in the rack adjuster to increase the figure recorded in instruction 87 by 0.9-1.3 kg (2-3 lb). The final figure may be less than 7.25 kg (16 lb) but must not exceed this figure.
89. Lock the rack adjuster in position with the set screw.
Torque Peak Check
With the input shaft rotated from lock-to-lock, the rolling resistance torque figures should be greatest across the center position (1.5 turns approximately from full lock) and equally disposed about the center position.
The condition depends on the value of shimming fitted between the valve and worm assembly inner bearing cup and the casing. The original shim washer value will give the correct torque peak position unless major components have been replaced.
Procedure
Checking Peak Torque:
90. With the input coupling shaft toward the operator, turn the shaft fully counter-clockwise.
91. Check the torque figures obtained from lock-to-lock using a spring balance cord and torque tool R01016.
Adjustments
92. Note where the greatest figures are recorded relative to the steering position. If the greatest figures are not recorded across the center of travel (i.e steering straight-ahead position), adjust as follows:
If the torque peak occurs before the center position, add to the shim washer value; if the torque peak occurs after the center position, subtract from the shim washer value.
Shim washers are available in these thicknesses: 0.03mm, 0.O7mm, 0.12mm and 0.24mm (0.0015 in, 0.003 in, 0.005 in and 0.010 in).
NOTE: Adjustment of 0.07mm (0.003 in) to the shim value will move the torque peak area by 1/4 turn approximately on the shaft.
93. Fit the pitman arm to the steering box using a new tab washer. Tighten the nut to 176 Nm (130 ft lbs).
94. Refit the steering box to the vehicle.
95. Replenish the system with the correct grade of fluid.
96. Test the system for leaks, with the engine running, by holding the steering hard on full lock in both directions.
NOTE: Do not maintain this pressure for more than 30 seconds in any one minute to avoid overheating the fluid and possibly damaging the seals.
97. Road test the vehicle.