New Holland LS140 Workshop Manual page 281

PROBLEM
Boom arms will not raise or raise
slowly
Boom or bucket leaks down or low
pressure
Boom and/or bucket will not move
smoothly, jerky.
Bucket will not tilt back, tilts back
slowly or tilts forward slowly
Bucket cylinder pin will not take
grease
SECTION 35 - HYDRAULIC SYSTEM
POSSIBLE CAUSE
Low oil flow from pump
Low relief valve pressure
Control linkage binding
Boom solenoid malfunctioning
Boom and bucket overloaded
Cylinder shafts are bent
Boom arms are binding at pivots
Boom circuit relief valve malfunc-
tioning
Bucket tilt valve spool is not return-
ing to center position, binding
Auxiliary hydraulic handle locked in
detent position
Control valve O rings leaking on
plugs or circuit relief valve
Air leaks at pump line and fittings
Low oil flow from pump
Worn or damaged pump
Valve spool is not in correct posi-
tion, spool binding
Bucket solenoid
malfunctioning
Cylinder shafts are bent
Cylinder seals are leaking
Bucket is overloaded
Auxiliary hydraulic handle locked in
detent position
Pin drilled incorrectly
35-12
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CORRECTION
Plugged inlet line or worn pump
Check pressure, replace valve if
pressure is not correct
Free linkage
Check solenoid operation
Reduce load
Rebuild or replace cylinders
Remove binding and lubricate link-
age
Check circuit relief valve pressure
setting
Correct binding, spool centering
spring damaged.
Return handle to neutral position
Repair control valve with seal kit
and replace O rings and back-up
rings
Tighten or replace line and fittings
Plugged inlet line, clean or replace
line
Check pump flow, rebuild or re-
place pump as necessary
Free control linkage, centering
spring damaged
Check solenoid operation
Rebuild or replace cylinders
Rebuild cylinders
Reduce load
Return handle neutral
Replace with new pin