Steering Gear Service - Toro Workman 3000 Series Service Manual

Steering Gear Service

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Torque to
180 – 210 ft–lb
(244 – 285 Nm)
when installing
pitman arm
1. Retaining ring
2. Housing end plug
3. Housing end plug seal
4. Rack piston seal
5. Rack piston o–ring
6. Rack piston end plug
7. Guide ball return
8. Ball return guide clamp
9. Screw/lockwasher ass'y
10. Chrome alloy ball
11. Rack piston
12. Steering gear housing
13. Pitman shaft
14. Side Cover seal
15. Housing side cover
16. Lash adjuster nut
The power steering gear has a recirculating ball system
which acts as a rolling thread between the worm shaft
and the rack piston. The worm shaft is supported by a
thrust bearing preload and two conical thrust races at
the lower end, and a bearing assembly in the adjuster
plug at the upper end.
The control valve in the steering gear directs the power
steering fluid to either side of the rack piston. The rack
Steering, Brakes and Suspension
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Figure 30
17. Flange hex bolt
18. Spool valve
19. Spool valve o–ring
20. Valve body
21. Needle bearing
22. Stub shaft seal
23. Stub shaft dust seal
24. Retaining ring
25. Adjuster plug lock nut
26. Adjuster plug
27. O–ring
28. Upper bearing race
29. Thrust roller bearing
30. Thrust bearing race
31. Thrust bearing spacer
32. Bearing retainer
piston converts the hydraulic pressure into a mechani­
cal force. If the steering system loses hydraulic pres­
sure, the vehicle can be controlled manually.
Turning the worm shaft moves the rack piston up or
down. The rack piston teeth mesh with the pitman shaft
sector. Turning the worm shaft turns the pitman shaft,
which turns the wheels through the steering linkage.
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33. Valve body ring
34. O–ring
35. O–ring
36. Stub shaft
37. O–ring
38. Steering worm
39. Thrust bearing race
40. Thrust roller bearing
41. Pitman arm nut
42. Lockwasher
43. Retaining ring
44. Seal backup washer
45. Pitman shaft seal
46. Pitman shaft seal
Workman 3000 Series
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