Manitowoc 777 Service And Maintenance Manual

Reference Only
TROUBLESHOOTING 777 SERVICE MANUAL
10-44 Published 10-01-2012, Control # 045-08
Test 14 – Adjusting Pump Charge Pressure Relief
The pump charge pressure must be measured to adjust the
charge pressure relief. Charge pressure should be
measured with a 0-500 psi gauge installed at system
pressure gauge ports M1 or M2, or at charge pressure gauge
port M3 if unused in the hydraulic circuit application (the
external filtration system prevents the use of M3 for testing
the auxiliary hoist and load drum pumps). Charge pressure
can also be measured at the transducer manifold as
indicated in Test 15. See Test 9 for location of pump test
ports M1, M2, and M3.
Install the gauge at the selected test port. Start the engine
and make sure all brakes are in the lock position, and all
hydraulic systems remain off. A measurement of
approximately 350 psi indicates correct charge pressure
relief.
To adjust charge pressure relief, loosen the adjustment lock
nut and turn the adjustment screw with a screwdriver until
350 psi is obtained. Torque the lock nut to 34-41 ft/lbs.
Remove the gauge and replace the port plug.
Item Description
1 System pressure port
2 Adjustment screw
3 Adjustment lock nut
P966
FIGURE 10-19
3
1
2

Manitowoc 777 Specifications

General

Brand	Manitowoc
Model	777
Category	Construction Equipment
Language	English