5.2.3 REASSEMBLING STEERING GEAR BOX

5.2.3 REASSEMBLING STEERING GEAR BOX (1) Reassembling control valve

① Install the spool in the valve housing, matching the "P" mark on the housing with the smaller chamfered diameter of the spool. ② Install the reaction piston and center spring in the valve body.

(2) Hold the gear case in a vise and apply grease on the oil seal inside the gear case.

(3) Install the ball nut assembly in the gear case, with the rack gear upward.

Fig. 5.19

Fig. 5.20

Fig. 5.21

Fig. 5.22

(4) Fill the oil seal with grease and apply a thin coat of grease on the "O"-ring at the gear case in the top cover fitting area. Slowly insert the column through the gear box. Forceful insertion might damage the "O"-ring.

Tightening torque: 34.3 - 53.0 N·m {350 - 540 kgf-cm (25 - 40 ft-lbs)}

(5) Install the thrust race, needle bearing and thrust race onto the worm shaft.

(6) Install the control valve assembly on the gear case, being careful not to allow the reaction piston to drop. Make sure that the "O"-ring of the gear case is securely settled in the groove.

(7) Install the jig shown in Figure 5.15 on the control valve. Then install the thrust race, needle bearing and thrust race in that order.

Fig. 5.23

Fig. 5.24

Fig. 5.25

Fig. 5.26

(8) Rotate the worm shaft counterclockwise to stop and hand tighten the nut until thrust bearing has no clearance, and mark the groove position in the shaft on the lock nut. Back off lock nut and check to see if the marked position remains unchanged.

If satisfactory, retighten the lock nut about 5°.

Shaft rotating torque: 0.98 N·m {10 kgf-cm (72 ft-lbs)} or less

(9) Caulk the lock nut.

(10) Install the "O"-ring in the groove of the end cover and attach the end cover.

Tightening torque: 37.3 - 56.9 N·m {380 - 580 kgf-cm (27.5 - 42.5 ft-lbs)}

(11) Install the ball nut assembly so that the center of the rack gear is aligned with the center of the side cover fitting window.

Fig. 5.27

Fig. 5.28

Fig. 5.29

Fig. 5.30

(12) Install the sector shaft on the gear case. Install the adjustment screw and shims in the sector shaft groove, and match the side cover screw hole with the adjustment screw. Install the side cover, turning the adjustment screw. At the same time, install an "O"-ring into the groove in the side cover.

Tightening torque: 34.3 - 53.0 N·m {350 - 540 kgf-cm (25.3 - 39.1 ft-lbs)}

(13) Set the pitman arm in the middle of the whole rotating angle of the worm shaft. Set a dial gauge at a position 150 mm (5.9 in) away from the pitman arm center and measure for looseness.

Looseness: below 0.3 mm (0.0118 in) Fig. 5.31

If there is a looseness of more than 0.3 mm (0.0118 in), adjust with the adjustment screw. After adjustment, install the packing and secure with lock nut. Finally, install the box nut.

Tightening torque: 19.6 - 29.4 N·m {200 - 300 kgf-cm (14.5 - 21.7 ft-lbs)} Fig. 5.32

Fig. 5.33

(14) Rotate the worm shaft to count the number of turns from stop to stop.

Total number of turns: 4 2 turns 3

(15) Rotate the worm shaft clockwise or counterclockwise to stop and release it. Make sure it returns about 50° smoothly.