POWER ASSISTED SYSTEM (POWER STEERING) > Steering Gearbox [LHD Model]
1. Clean all the disassembled parts, and check for wear, damage or any other faults, then repair or replace as necessary.
2. When disassembling, check the inside of gearbox for water. If any water is found, carefully check the boot for damage, input shaft dust seal, adjusting screw and boot clips for poor sealing. If faulty, replace with new parts.
|
No. |
Parts |
Inspection |
Corrective action |
|
1 |
Input shaft |
(1) Bent input shaft (2) Damage on serration |
If the bend or damage is excessive, replace the entire gearbox. |
|
2 |
Dust seal |
(1) Crack or damage (2) Wear |
If the outer wall slips, the lip is worn out or damage is found, replace it with a new part. |
|
3 |
Rack & pinion |
Poor mating of rack with pinion |
(1) Adjust the backlash properly. By measuring the turning torque of the gearbox and sliding resistance of rack, check if the rack & pinion engage uniformly and smoothly with each other. (Refer to “Service limit”.) (2) Pull out the entire rack to allow viewing of the teeth, and check for damage. Even if abnormality is found in either (1) or (2), replace the entire gearbox. |
|
4 |
Gearbox unit |
(1) Bending of the rack shaft (2) Bending of the cylinder portion (3) Crack or damage on the cast iron portion |
Replace the gearbox with a new part. |
|
(4) Wear or damage on rack bushing |
If the free play of rack shaft in radial direction is out of the specified range, replace the gearbox with new part. (Refer to “Service limit”.) | ||
|
(5) Wear on input shaft bearing |
If the free play of input shaft in radial and axial direction is out of the specified range, replace the gearbox with a new part. (Refer to “Service limit”.) | ||
|
5 |
Boot |
Crack, damage or deterioration |
Replace. |
|
6 |
Tie-rod |
(1) Looseness of ball joint (2) Bend of tie-rod |
Replace. |
|
7 |
Tie-rod end |
Damage or deterioration of dust seal |
Replace. |
|
8 |
Adjusting screw spring |
Deterioration |
Replace. |
|
9 |
Boot clip |
Deterioration |
Replace. |
|
10 |
Sleeve |
Damage |
Replace. |
|
11 |
Pipe |
(1) Damage to flared surface (2) Damage to flare nut (3) Damage to pipe |
Replace. |
Make a measurements as follows. If it exceeds the specified service limits, adjust or replace.
NOTE:
When making a measurement, vise the gearbox using ST. Never vise the gearbox by inserting aluminum plates etc. between vise and gearbox.
| ST1 926200000 | STAND |
| ST2 34199AG000 | BOSS D |
3. RACK SHAFT PLAY IN THE RADIAL DIRECTION
Right-turn steering:
Service limit
0.12 mm (0.005 in) or less
Condition
Weighting point
L1: 10 mm (0.39 in)
P: 98 N (10 kgf, 22 lb)
Measuring point
L2: 25 mm (0.98 in)
Left-turn steering:
Service limit
Direction

0.3 mm (0.012 in) or less
Direction

0.15 mm (0.0059 in) or less
Condition
L: 5 mm (0.20 in)
P: 98 N (10 kgf, 22 lbf)
In radial direction:
Service limit
0.26 mm (0.01 in) or less
Condition
P: 98 N (10 kgf, 22 lb)
In axial direction:
Without play
5. TURNING RESISTANCE OF GEARBOX
Using the ST, measure the gearbox turning resistance.
| ST 34099PA100 | SPANNER |
Service limit:
Maximum allowable resistance:
11.3 N (1.15 kgf, 2.54 lb) or less
Difference between right and left turning resistance:
24% or less
|
(1) |
Power cylinder |
(3) |
Rack piston |
(5) |
Input shaft |
|
(2) |
Cylinder |
(4) |
Rack axle |
(6) |
Valve housing |
1. Lift up the vehicle.
2. If a fluid leak is found, clean the fluid completely from the suspect area, and turn the steering wheel 30 to 40 times to the left and right from lock to lock, with the engine running, and check again for leaks immediately, and also after a few hours have passed.
3. Cause and solution for oil leakage from “a”
The oil seal is damaged. Replace the valve assembly with a new part.
4. Cause and solution for oil leakage from “b”
The torsion bar O-ring is damaged. Replace the valve assembly with a new part.
5. Cause and solution for oil leakage from “c”
The oil seal is damaged. Replace the valve assembly or oil seal with a new part.
6. Cause and solution for oil leakage from “d”
The pipe is damaged. Replace the faulty pipe or O-ring.
7. Cause and solution for oil leakage from “g”
The hose is damaged. Replace the hose with a new part.
8. If leak is other than a, b, c, d or g, or if oil is leaking from gearbox, move the right and left boots toward tie-rod end side, respectively, with the gearbox mounted to the vehicle, and remove fluid from surrounding portions. Then, turn the steering wheel from lock to lock 30 to 40 times with the engine running, then re-inspect the leaking area immediately after and several hours after this operation.
(1) Leakage from “e”
The cylinder seal is damaged. Replace the rack bushing with a new part.
(2) Leakage from “f”
There are two possible causes. Perform the following step first. Remove the pipe assembly B from the valve housing, and close the circuit using ST.
| ST 926420000 | PLUG |
Turn the steering wheel from lock to lock 30 to 40 times with the engine running, then re-inspect the leaking area immediately after and several hours after this operation.
• If leakage from “f” is noted again:
The oil seal of pinion and valve assembly is damaged. Replace the pinion and valve assembly with a new part. Or replace the oil seal and the parts that are damaged during disassembly with new parts.
• If oil leaking from “f” stops:
The rack housing oil seal is damaged. Replace the oil seal and the parts that are damaged during disassembly with new parts.