LS tractor 30139708, Operator'S Manual

Page: 38 / 90

36
TROUBLE SHOOTING
Problem Possible cause Correction
System relief valve squeals.
Hydraulic oil viscosity
too heavy or incorrect oil Check oil number and viscosity, refill correct
hydraulic oil.
Excessive load in bucket.
Weight exceeds specified
backhoe capacity.
Reduce load.
Relief valve setting below
specifications.
Check and reset valve setting as needed.
Hydraulic hose, tube line
or quick disconnect
coupler restriction. Check for evidence of restriction in hydraulic
oil flow. Repair or replace defective
components.
Backhoe drops with
control valve spool in
"Centered" position (No
external oil leakage
evident.)
Cylinder piston assembly
leakage.
Check cylinders for leakage.
Note: A gradual drop over
an extended period of
time is a normal condition.
Control valve internal
leakage.
Replace control valve and recheck.
Control valve spool(s) will
not return to centered
position.
Control lever linkage
binding.
Determine origin of binding and repair.
Control valve spool
centering is broken.
Replace centering spring.
Control valve spool
binding in valve body
spool bore.
Disassemble valve for inspection and repair.
External hydraulic fluid
leakage.
Loose hydraulic
connection.
Tighten loose connections.
Defective hydraulic hose,
tube line, adapter fitting
or adapter fitting O-ring.
Check for origin of oil leak and replace
defective part.
Control valve O-rings
defective.
Replace defective O-rings.
Control valve spool or
body damaged or worn.
Replace control valve.
Cylinder rod packing set
leakage.
Check cylinders for leakage. Repair as needed.