Toro Groundsmaster 3500 30807 Service Manual page 147

IMPORTANT: If a piston pump failure occurred, re-
fer to Traction Circuit (Closed Loop) Component
Failure in this chapter for information regarding the
importance of removing contamination from the
traction circuit.
NOTE: The traction circuit charge relief valve and the
bleed off valve for traction circuit cooling are attached to
the piston pump back plate assembly (Fig. 56). The
back plate assembly must be removed from the piston
pump/hydrostat to service either the relief valve or the
bleed off valve.
IMPORTANT: The shim kit is used to replace the
original crush ring (not shown) in the cover plate. If
the swash plate, cover plate or housing is replaced
during servicing, the old crush ring must be re-
placed. See Piston Pump Crush Ring Replacement
in this chapter in conjunction with the Eaton service
manual at the end of this chapter for additional in-
formation.
NOTE: For repair of the piston pump, see the Eaton
Medium Duty Piston Pump Repair Information Model
70160 Variable Displacement Piston Pump at the end of
this chapter.
Groundsmaster 3500
CHARGE RELIEF
VALVE
7
8
9
BLEED OFF
VALVE
11
12
13
1. Back plate assembly
2. Charge relief valve
3. Bleed off valve
4. O−ring
5. Housing
6. Poppet
7. Spring
Page 5 − 89
4
5
6
2
10
Figure 56
8. Washer
9. Retaining ring
10. Bleed off valve
11. Spring
12. O−ring
13. Cartridge
Hydraulic System
1
3