Stellar Industries 28000 - Manual (Page 55)

51 Troubleshooting 51
Operation slow down - con’t Pump is slipping due to excessive oil
temperature, this is a factor which will
increase with worn components.
Filters are dirty.
Obstruction has occurred in boom hold-
ing valve.
Check pump GPM with flow meter if it
is suspected to be faulty.
Replace filters.
Replace or clean holding valve.
Operation slow down - con’t Defective flow valve. Replace valve.
Boom drifts when loaded and controls
neutralized. Hydraulic oil is bypassing at piston
seal.
Main or secondary cylinder holding
valves are defective or contaminated.
Replace cylinder.
Clean or replace holding valves.
Unusual noise in operation. Cavitation is occurring due to low
hydraulic oil supply.
Restriction or collapse of suction line
has occurred.
Suction line screen is clogged and
requires replacement.
Add oil and cycle cylinders to get air
out of system.
Inspect suction line for damage.
Replace or clean screen.
Unusual noise in operation - con’t Bypass settings on relief valve are too
low.
Relief valve is damaged.
Contact customer service for correct
relief setting.
Replace relief valve.
Outriggers fail to retract Control valve is inoperative.
Cylinder seals or holding valve are
defective
Hydraulic lines are restricted or rup-
tured.
If outriggers retract using manual func-
tion, it is a probable electrical problem -
check continuity.
Replace seals or holding valve.
Inspect and replace hydraulic lines.
Outriggers fail to retract-con’t Broken electrical wire going to outrig-
ger switch to the valve bank. Check continuity of circuit.
Outriggers yield or drift. Control valve is inoperative.
Cylinder or check valve is defective.
Hydraulic lines are restricted or rup-
tured.
Clean or replace pulsar solenoid valve.
Replace holding valve.
Check hoses for damage and replace.
Problem Possible Cause Possible Solution