20 Owner Service
51861 (Rev. 6/16/2006)
TROUBLESHOOTING
PROBLEM POSSIBLE CAUSE SOLUTION
Noisy pump caused by cavitation Oil too heavy Change to proper viscosity.
Oil filter plugged Replace filter.
Suction line plugged or too small Cle an line and check for size.
Suction line kinked Replace line.
Oil heating Oil supply low Fill reservoir.
Contaminated oil Drain reservoir, change filter, and
refill with clean oil.
Setting of relief valve too high or
too low
Set to correct pressure.
Pump operating too fast Do not exceed recommended
rpm PTO speed.
Shaft seal leakage Worn shaft seal Replace shaft seal.
Foaming oil Low oil level Fill reservoir.
Air leaking into suction line Tighten fittings.
Wrong kind of oil Drain and refill reservoir with non-
foaming oil.
Moisture in oil Keep oil temperature below 180°
and continue to operate as oil
dries out, or replace oil and purge
system if foaming is excessive.
Boom drops as dipper or bucket
cylinder lever is activated while
boom control is in raised position
Load check valve leaking Clean or replace check valve
assembly.
Jerky operation Hydraulic hose s plumbed
incorrectly
Check hydraulic plumbing
schematic and correct hose
routing as required.