There are four replenishing/high pressure relief valves (Item 1) [Figure 30-40-1] in the hydrostatic pump
assembly. Two are located at the top of the pumps and two at the bottom of the pumps.
(See HYDROSTATIC SYSTEM INFORMATION on Page 30-10-1.)
NOTE: The two top valves are for the forward drive loop and the two bottom valves are for the reverse drive loop.
Remove the high pressure relief valve (Item 1) [Figure 30-40-2] from the pump.
Assemble: Tighten the plug to 30-50 ft.-lbs. (41-68 Nm) torque.
Check for damage and replace as needed.
Check the O-rings (Items 2 & 3) [Figure 30-40-2] for damage and replace as needed.
If the high pressure relief valve must be replaced, it must be replaced as a complete unit.
The pressure setting for a new high pressure relief valve is 5000 PSI (34475 kPa).