Traction Circuit Charge Pressure - Toro Groundsmaster 580-D Service Manual

TEST NO. 2: Traction Circuit Charge Pressure
1. Hydraulic oil must be at operating temperature.
2. Connect a 1,000 psi gauge onto charge pressure test
port (Fig. 10).
3. Start the engine and put throttle at idle position
(approx. 1,200 rpm) with no load on the system.
TESTER READING TO BE:
230 ± 10 PSI
(Pump S/N Below A-96-01-XXXXX)
285 ± 10 PSI
(Pump S/N A-96-01-XXXXX & Up)
4. If there is no pressure or pressure is too low, check
for restriction in pump intake line. Inspect charge relief
valve and valve seat. Charge pressure can be adjusted
by changing shim thickness behind the spring. Check
for sheared charge pump key. If necessary, check
for internal damage or worn parts in charge pump.
5. Also with pressure gauge still connected to the charge
pressure test port, take a gauge reading while operating
the machine in forward and reverse. Start the engine and
put the throttle at full engine speed. Apply the brakes and
push the traction pedal forward , then reverse.
6. If pressure is good under no load, but drops below
specification when under traction load, the piston pump
and/or traction motor(s) should be suspected of wear and
inefficiency. When the pump and/or traction motor(s) are
worn or damaged, the charge pump is not able to keep
up with internal leakage in the traction circuit
components.
Groundsmaster® 580-D
Deck drive test ports on newer models at deck motor.
Older model shown.
Page 4 - 25 Rev. E
Figure 10
Figure 10
Testing