Toro Groundsmaster 4500-D Series Service Manual page 163

Procedure for Piston (Traction) Pump Flow Test (continued)
Groundsmaster ® 4500-D/4700-D
19245SL Rev A
3. Thoroughly clean junction of hydraulic hose and right side fitting on bottom
of piston pump (forward port)
pump fitting.
4. Install tester with pressure gauge and flow meter in series between piston
pump fitting and disconnected hose to allow flow from traction pump to tester.
Use hydraulic hose kit (see
machine. Make sure that fitting and hose connections are properly tightened.
Also, make sure the flow control valve on tester is fully open.
5. Start engine and increase engine speed to high idle speed.
6. Slowly push traction pedal to fully forward position. Keep pedal fully
depressed in the fully forward position.
7. Have second person watch pressure gauge on tester carefully while slowly
closing the flow control valve until 69 bar (1000 PSI) is obtained. Verify with
the InfoCenter display that the engine speed is still at the correct high idle
speed.
Note: If engine speed drops during testing, pump flow will decrease and
flow test results will be inaccurate.
8. Observe flow gauge. Flow indication should be approximately 113 LPM (30
GPM).
9. Release traction pedal to the neutral position, open flow control valve on
tester and shut off engine. Record test results.
10. If flow is less than 91 LPM (24 GPM), consider the following:
A. The traction pedal is not calibrated correctly (see
Sensor Calibration (page
B. The piston pump swash plate is not being rotated fully (e.g. traction
speed is not set to 100%).
C. The forward traction relief valve is leaking or faulty.
D. The piston pump needs to be repaired or replaced as necessary.
11. Make necessary repairs before performing any additional traction circuit tests.
12. When testing is complete, disconnect tester from pump fitting and machine
hydraulic hose. Reconnect hose to pump fitting. Lower machine to ground.
(Figure 71). Disconnect hose from right side
Special Tools (page
6–21)).
Page 5–61
2–16)) to connect tester to
Traction Pedal Position
Hydraulic System: Testing