Hydraulics Troubleshooting; Testing Charge Pressure - Toro GROUNDSMASTER 325-D Troubleshooting Manual

TORO GM 345 / 325-D
Troubleshooting
To test the hydrostatic system there are several test ports on the hydrostatic unit.
1. Charge pressure test port, (located on the left side rear of the hydrostatic unit, next to the steering and lift
supply line).
2. Forward and reverse drive pressure test ports, (located in the middle section of the hydrostatic unit).
Forward drive is the RH test port.
Reverse drive is the LH test port.
There is also test ports located on the underside of the hydrostatic unit. (Use these test ports for 4WD
units).

Testing charge pressure.

Remove the test port plug using a 3/16" allen wrench.
Connect 1000 psi gauge using a 1/8 NPT adapter screwed into the pump.
Operate engine at 3200 RPM.
Charge pressure should read 70 - 150 psi.
Low charge pressure
1. Possible causes:
Plugged hydraulic filter.
Low engine RPM.
Defective charge relief valve.
Defective implement relief valve.
Worn charge pump.
Worn drive pump.
Worn drive motor.
2. Performance results:
Noisy operation. (Drive circuit not kept full)
Poor hill performance. (Slows or stops on hills)
System over heating. (low oil cooler flow)
Complete drive failure.(unit stops moving)
Pump or motor failure. (Lack of lubrication)
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Notes
Hydraulics
45