High Pressure Relief/Check Valve Replacement - Toro Reelmaster 5500-D Service Manual

High Pressure Relief/Check Valve Replacement

1. Park machine on a level surface, lower cutting units,
stop engine, engage parking brake, and remove key
from the ignition switch.
2. Remove check/high pressure relief valve hex plug
(Fig. 77).
3. Remove the valve cartridge assembly. Inspect the
valve and mating seat in the housing for damage or for-
eign material. It will be necessary to replace the center
section if the seat is damaged.
IMPORTANT: The relief valves are factory set and
should not be tampered with, except to replace the
entire valve cartridge.
4. The valve cartridge is retained in the special plug by
a circlip. The check valve spring may be removed from
the special plug by pulling out at a slight angle. When re-
assembling, install the check valve spring into the spe-
cial plug with its larger diameter toward the plug, and
snap the valve cartridge into position in the plug.
Note: The forward and reverse valves are different.
The seating surface of the "reverse" check/high pres-
sure relief valve has a machined groove in it. Installing
the "reverse" check/high pressure relief valve in the
wrong port may cause performance problems.
5. Reinstall the valve cartridges with O-rings into the
housing and tighten the plugs to a torque of 30 to 70 ft.-lb
(41 to 95 N-m).
6. Before starting the engine check the oil level in the
differential housing and add the correct oil as necessary.
Start the engine and let it run for one to two minutes, then
turn the engine off and check the oil level again. Check
transmission for leaks.
Reelmaster 5500-D
1. Forward check/high
pressure relief valve
2. Reverse check/high
pressure relief valve
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5
4
3
1
MACHINED
GROOVE
2
3
4
5
Figure 77
3. Spring
4. O-ring
5. Plug
Hydraulic System (Rev. C)