Abnormal pump noise: Worn pistons and slippers, scratched valve plate; air ingress in suction line, contaminated hydraulic oil
Insufficient output pressure: Internal leakage caused by worn piston pairs and aged seals; faulty pressure regulator, boom, bucket and steering pressure fails to reach rated value
Slow boom lifting, bucket operation and heavy steering: Reduced volumetric efficiency of hydraulic pump and insufficient output flow; clogged suction filter element, excessive suction resistance
Excessively high hydraulic oil temperature: Severe internal leakage inside pump and increased frictional heat; incorrect hydraulic oil grade or deteriorated oil
Pump housing leakage: Aged and damaged end cover seals and O-rings; uneven tightening torque of bolts, cracked housing
Purchasing Recommendations
Verify the stamped part number on old pump and wheel loader model WA470-6 before placing order. Hydraulic pumps of WA470-6 differ from WA470-3 / WA470-5, they cannot be directly interchanged.
New assembly or remanufactured assembly are available. For reman pumps, confirm factory test report and warranty period
Replace full seal kit during installation, inspect hydraulic oil and suction filter to avoid premature wear and damage of new pump
Inspection upon arrival: Check pump housing for dents and cracks, intact oil port threads and legible nameplate. Perform no-load test before installation to check pressure and noise
Storage requirement: Store in dry and shaded area, seal oil ports against dust and moisture