Hydraulic System

Symptom Problem Solution

No Hydraulic Functions

Pilot enable/boom down switch at pilot lockout position

Push switch to pilot enable position.

Electrical circuit

Push pilot enable/boom down switch to boom down position. If hydraulics work, check fuse. See your authorized dealer.

Priority valve

See your authorized dealer.

Hydraulic system relief valve

See your authorized dealer.

Hydraulic pump control

See your authorized dealer.

Hydraulic pump

See your authorized dealer.

Slow Hydraulic Functions

Cold oil

Warm oil up.

Slow engine speed

See your authorized dealer.

Suction line air leak

Check for foamy oil.

Low oil supply

Add recommended oil. (See Fuels and Lubricants, Section 45.)

Wrong oil viscosity

Use recommended oil. (See Fuels and Lubricants, Section 45.)

System relief valve malfunctions or misadjusted

See your authorized dealer.

Oil leaking past cylinders or control valve

See your authorized dealer.

Blocked or damaged line

Inspect lines.

Pilot control valve pressure low

See your authorized dealer.

Pilot control valve

See your authorized dealer.

Binding loader control valve spool

Inspect valve.

Leaking steering valve

See your authorized dealer.

CED,OUO1032,523 -19-30MAR98-1/4


Symptom Problem Solution

Noisy Hydraulic Pump

Low oil supply or wrong viscosity

Fill reservoir with recommended oil. (See Fuels and Lubricants, Section 45.)

Plugged or pinched suction line

Clean or replace line.

Air in oil

Check for foamy oil. Tighten connections. See your authorized dealer.

Loose or missing hydraulic line clamps

Tighten or replace clamps.

Hydraulic lines in contact with frame

See your authorized dealer.

Worn or damaged pump

See your authorized dealer.

Boom Float Function Does Not Work

Boom float switch OFF

Push switch to ON position.

Low pilot control pressure

Increase engine speed to fast idle. See your authorized dealer.

Electromagnet in controller

See your authorized dealer.

Pilot control valve

See your authorized dealer.

Loader control valve spool binding in bore

See your authorized dealer.

One Hydraulic Function Does Not Work

Pilot control valve

See your authorized dealer.

Stuck open circuit relief valve

See your authorized dealer.

Oil leaking past cylinder packings

See your authorized dealer.

Blockage in oil lines or valve

See your authorized dealer.

Loader control valve spool stuck in bore

See your authorized dealer.

CED,OUO1032,523 -19-30MAR98-2/4


Symptom Problem Solution

Low Hydraulic Power

Low relief valve setting

See your authorized dealer.

Low circuit relief valve setting

See your authorized dealer.

Leaking relief valve

See your authorized dealer.

Worn hydraulic pump

See your authorized dealer.

Pilot control valve

See your authorized dealer.

Function Drifts Down

Leaking cylinders

See your authorized dealer.

Leaking seals in circuit relief valve or valve stuck open

See your authorized dealer.

Boom lower solenoid valve

See your authorized dealer.

Leaking loader control valve

See your authorized dealer.

Boom Down Does Not Work (Engine OFF, Key ON)

Pilot enable/boom down switch not held in boom down (momentary) position

Push and hold pilot enable/disable switch to momentary position as loader control lever is moved.

Pilot enable/boom down fuse failed

Replace fuse.

Boom down solenoid

See your authorized dealer.

Pilot enable/disable switch

See your authorized dealer.

CED,OUO1032,523 -19-30MAR98-3/4


Symptom Problem Solution

Hydraulic Oil Overheats (Machine Shifts to Low Speed Automatically)

Low oil viscosity in hot weather

Use recommended oil. (See Fuels and Lubricants, Section 45.)

Excessive load

Reduce load.

Two-speed fan slow or not rotating

See your authorized dealer.

Cylinder leakage

See your authorized dealer.

Incorrect loader system relief or circuit relief valve setting

See your authorized dealer.

Restriction in oil lines or loader valve

Inspect for dented or kinked lines.

Leaking relief valve

See your authorized dealer.

Worn hydraulic pump (internal leakage)

See your authorized dealer.

Hydraulic Oil Foams

Low oil level

Add recommended oil. (See Fuels and Lubricants, Section 45.)

Wrong oil

Change to recommended oil. (See Fuels and Lubricants, Section 45.)

Water in oil

Drain oil from reservoir and cylinders. Fill with recommended oil. (See Fuels and Lubricants, Section 45.)

Suction lines (air leak in system) loose or malfunction

See your authorized dealer.

Pilot Control Valve Leaking

Leaking seals

See your authorized dealer.

CED,OUO1032,523 -19-30MAR98-4/4