Toro Groundsmaster 360 Service Manual page 75

The Transmission Piston Pump Flow Test should be
performed if a traction circuit problem is identified. This
test will determine if hydraulic flow from a transmission
piston pump is correct.
Procedure for Transmission Piston Pump Flow
Test:
IMPORTANT: Traction
Groundsmaster 360 is approximately 15 GPM (57
LPM). Use 40 GPM Hydraulic Tester #AT40002 (pres-
sure and flow) for this test (see Special Tools in this
chapter).
1. Make sure hydraulic oil is at normal operating tem-
perature. Also, make sure that traction drive is correctly
adjusted for the neutral position and that the hydraulic
tank is full.
WARNING
Before disconnecting or performing any work on
the hydraulic system, all pressure in the system
must be relieved. See Relieving Hydraulic System
Pressure in the General Information section.
2. Park machine on a level surface with the cutting deck
lowered and off. Make sure engine is off.
3. Read Precautions for Hydraulic Testing listed at the
beginning of this section.
WARNING
Before jacking up the machine, review and follow
Jacking Instructions in Chapter 1 - - Safety.
4. Raise and support machine with jack stands so that
all drive wheels are off the ground. In this test, the drive
wheels need to spin freely to allow hydraulic flow
through the traction circuit. Make sure that the parking
brake is not applied.
5. Thoroughly clean area surrounding traction circuit
hoses on top of transmission (Fig. 30 or 31). Determine
which piston pump is to be tested.
6. Disconnect hydraulic hose from transmission pump
outlet fitting for piston pump to be tested (Fig. 30 or 31):
Piston Pump to be Tested
Right Side Pump
Left Side Pump
Groundsmaster 360
circuit flow for the
Pump Outlet
Port A
Port C
Page 4 - - 41
4WD Machine
Port D
Port C
Port B
Port A
Figure 31
7. Install 40 GPM hydraulic tester (pressure and flow)
in series between the pump outlet fitting and the discon-
nected hose. Make sure that the tester flow arrow points
from the pump outlet and toward the hose. Make sure
the flow control valve on the tester is fully open.
8. Disconnect balancing hose from transmission fitting
closest to transmission pump outlet fitting for pump to be
tested (Fig. 30 or 31). Install steel cap on fitting and steel
plug in balancing hose.
9. Sit in the operator seat, start engine and run at low
idle speed (1300 RPM). Check for any hydraulic leak-
age from test connections and correct before proceed-
ing with test.
10.With engine running, move throttle so engine is run-
ning at high idle speed (3100 to 3150 RPM). Use a pho-
totac to measure engine speed.
11. Have operator slowly push traction pedal to the full
forward position.
12.Slowly close tester flow control valve until pressure
gauge reads 1000 PSI (69 bar). Verify with a phototac
that the engine speed is still 3100 to 3150 RPM.
13.Observe flow gauge on tester. TESTER READING
should be approximately 14 GPM (53 LPM) for a traction
pump in good condition.
14.Open tester flow control valve, release traction pedal
to the neutral position and stop engine. Record test re-
sults.
15.Lower pump flow would result in reduced traction cir-
cuit performance. If flow is less than 12.5 GPM (47.4
LPM) or a pressure of 1000 PSI (69 bar) cannot be ob-
tained:
A. The transmission bypass valve(s) may be open
or damaged.
Balancing Hose
Balancing Hose
Hydraulic System