Toro GroundsmasterR 4300-D Service Manual page 71

CAUTION
Before opening hydraulic system, operate all hy-
draulic controls to relieve system pressure and
avoid injury from pressurized hydraulic oil. See
Relieving Hydraulic System Pressure in the Gen-
eral Information section of this chapter.
4. Raise and support operator seat to allow access to
hydraulic pump.
5. Thoroughly clean the ends of the hydraulic tubes
connected to the oil filter and traction pump inlets (Fig.
40). Disconnect hydraulic tubes from oil filter inlet and
traction pump inlet. Remove two (2) flange head screws
that secure oil filter adapter to frame. Remove oil filter
assembly and hydraulic tube from machine.
IMPORTANT: Make sure that the oil flow indicator
arrow on the flow meter is showing that the oil will
flow from the hydraulic tube, through the tester and
into the traction pump.
6. Install tester with pressure gauges and flow meter in
place of the removed oil filter assembly and hydraulic
tube. Connect tester inlet hose to the hydraulic tube.
Connect the tester outlet hose to the traction pump fit-
ting. Make sure the flow control valve on tester is ful-
ly open.
7. Make sure that the traction pedal is in neutral, the
steering wheel is stationary and the parking brake is en-
gaged.
8. Start engine and run at idle speed. Check for any hy-
draulic leakage from test connections and correct be-
fore proceeding with test.
9. Move throttle to full speed (3200 RPM). Use a
tachometer to verify that engine speed is correct.
IMPORTANT: The gear pump is a positive displace-
ment type. If pump flow is completely restricted or
stopped, damage to the pump, tester or other com-
ponents could occur.
10.While watching pressure gauges, slowly close the
tester flow control valve until 800 PSI (55 bar) is ob-
tained on gauge.
Groundsmaster 4300--D
FLOW TESTER READING TO BE: A pump in good
condition should have a flow of approximately 4.9
GPM (18.5 LPM) at 800 PSI (55 bar).
11. Open the tester flow control valve, stop engine and
record test results.
12.If flow is less than 4.4 GPM (16.6 LPM) or a pressure
of 800 PSI (55 bar) cannot be obtained, consider that a
pump problem exists. Check for restriction in pump in-
take line. If intake is not restricted, remove gear pump
and repair or replace pump as necessary (see Gear
Pump in the Service and Repairs section of this chap-
ter).
NOTE: If the flow from gear pump (P3) is low, the opera-
tion of both the charge circuit and the steering circuit will
be affected.
13.After testing is completed, make sure that engine is
stopped, then relieve hydraulic system pressure (see
Relieving Hydraulic System Pressure in the General In-
formation section of this chapter). Remove tester and
then install oil filter assembly and hydraulic tube to ma-
chine.
14.Lower and secure operator seat.
4
1. Hydraulic tube
2. Oil filter / filter adapter
Page 4 - - 39
2
3
1
Figure 40
3. Hydraulic tube
4. Gear Pump (P3)
Hydraulic System