Operating Instructions, Form No. 102838, Back sheet 3 of 3
PROBLEM CAUSE SOLUTION
HYDRAULIC SCHEMATIC
Cylinder(s) will not retract.
Pump delivers excess oil
pressure
1. Check the system pressure; if
the pressure is zero, the control
valve is releasing pressure and
the problem may be in the
cylinder(s), mechanical linkage
connected to cylinder(s), or
quick disconnect couplings.
2. Defective valve.
1. Relief valve not properly set.
1. Check the cylinders for broken
return springs, and check
couplers to ensure that they are
completely coupled.
Occasionally couplers have to
be replaced because one check
does not stay open in the
coupled position.
2. Check valve operation and
inspect parts. Replace if
necessary.
1. Adjust the relief valve.
HYDRAULIC
SCHEMATIC (RE
F.)
TO VALVE
UNLOADING VALVE
500 P.S.I.
SUPERCHARGE
VALVE
160 P.S.I.
HIGH PRESSURE
RELIEF VALVE
10,400 P.S.I.
M
HP
LP
LP
