Textron JACOBSEN GP400, Technical/Repair Manual

Page: 149 / 354

HYDROSTATIC POWER TRAIN
4252490-Rev A 5-31
5
Hydrostatic System Operating Hot
Excessive Traction Pump Noise
Probable Cause Remedy
Hydraulic oil not at correct level in reservoir. Fill reservoir to correct level. (Refer to “Parts and Maintenance
Manual” for correct oil specifications.)
Tow valve open. Close tow valve. (Refer to “Safety and Operation Manual.”)
Oil cooler has dirt or debris in fins. Clean oil cooler fins of dirt and debris.
Faulty flushing valve. Inspect and repair. (See “Flushing Valve” on page 5-55.)
Slippage in pump or motor. Perform instrument tests. (See “Instrument Test Overview” on
page 5-35.)
Faulty charge pressure relief valve. Test charge pressure relief valve. (See “Charge Pressure Test” on
page 5-36.) Repair or replace charge pressure relief valve as
needed. (See “Traction Pump and Control” on page 5-50.)
Probable Cause Remedy
Hydraulic oil not at correct level in reservoir. Fill reservoir to correct level. (Refer to “Parts and Maintenance
Manual” for correct oil specifications.)
Hydraulic oil cold. Warm hydraulic oil to operating temperature.
Air in hydraulic system (air bubbles in hydraulic oil). Check suction line for air leaks. Repair as needed. Operate
various hydraulic systems until hydraulic system is free of air.
Traction pump worn or damaged. Test pump. (See “Traction System Test” on page 5-37.) Repair or
replace pump as needed. (See “Traction Pump and Control”
on page 5-50.)