Toro Greensmaster 3150 Service Manual page 53

Procedure for Gear Pump (P2) Flow Check:
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately 10
minutes.
2. Park machine on a level surface with the cutting
units lowered. Make sure engine is off and the parking
brake is engaged. Make sure the hydraulic tank is full.
CAUTION
Before continuing further, read and become fa-
miliar with Precautions for Hydraulic Testing.
3. Disconnect hydraulic hose from the discharge fitting
of gear pump (P2) (end pump section).
4. Install tester in series with the gear pump and the
disconnected hose. Make sure that tester flow arrow
points from the pump discharge and toward the discon-
nected hose. Make sure flow control valve on the
tester is fully open.
5. Make sure that traction pedal and lift control are in
neutral and the parking brake is engaged.
6. Operate engine at full speed (2850 + 50 RPM).
7. Watch flow and pressure gauges carefully while
slowly closing the flow control valve on the tester until
the pressure gauge reads 800 PSI (55.2 bar).
8. Minimum flow gauge reading should be 3.1 GPM.
Record test results.
9. Open control valve on tester and shut off engine.
10. If specification is not met, check for restriction in the
pump intake line. If no restriction is found, repair or re-
place gear pump (P2).
Procedure for Implement Relief Valve (R5) Pressure
Check:
CAUTION
Do not allow pressure to exceed 1400 PSI (82.8
bar).
1. Measure and record charge relief valve (R4) pres-
sure (see TEST NO. 3: Charge Relief Valve (R4) Pres-
sure Check in this chapter).
2. Use same tester connections as described above
(steps 3 and 4). Fully open control valve on the tester.
Greensmaster 3150
3. Start and run engine at full speed (2850 + 50 RPM).
4. Watch the pressure gauge on the tester and move
the lift lever to the raise position. Momentarily hold the
lift lever with the cutting units fully raised causing the re-
lief valve (R5) to open. Record pressure at which the re-
lief valve (R5) opens.
5. Open control valve on tester and shut off engine.
Note: The implement relief valve (R5) is in series with
charge relief valve (R4). (R4) pressure will affect (R5)
pressure.
6. Implement relief valve (R5) pressure should be
1050 to 1250 PSI (72.5 to 86.3 bar) higher than the
charge relief valve (R4) pressure (e.g. if the charge re-
lief valve pressure is 100 PSI, the implement relief valve
(R5) pressure should be 1150 to 1350 PSI).
7. If relief valve (R5) pressure is incorrect, inspect re-
lief valve (R5) located in the steering control valve (see
Steering Control Valve Service in the Service and Re-
pairs section of this Chapter). Clean or replace relief
valve as needed.
IMPORTANT: Hold steering wheel at full lock only
long enough to get a system pressure reading.
8. Relief Valve (R5) is also activated by the steering
system. With tester still connected to gear pump P2,
start engine and watch the pressure gauge. Turn the
steering wheel completely in one direction and hold. Re-
lief valve (R5) should open just after rear wheel gets to
the full lock position. Relief pressure measured with the
steering system should be similar to results in step 5.
Note: Lower Cutting Units Relief Valve (R2) Pressure
can be measured with tester positioned as described in
this check (see TEST NO. 5 in this chapter).
9. If testing is complete, disconnect tester from the
pump and hose. Reconnect hose to the pump.
Page 4 – 29 Rev. C
Hydraulic System