Toro Reelmaster 5010- H Service Manual page 79

The lift relief valve (SVRV) pressure test should be per-
formed to make sure that the lift circuit relief pressure is
correct.
Procedure for Lift Relief Valve (SVRV) Pressure Test
1. Park machine on a level surface with the cutting units
lowered and disengaged. Make sure engine is off. Apply
the parking brake.
2. Read Precautions For Hydraulic Testing in this sec-
tion.
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.
3. Raise and support operator seat to allow access to
hydraulic pump assembly.
4. Thoroughly clean test port attached to tee fitting on
st
1 gear pump section (P1) (Fig. 40). Connect a 5000
PSI (350 bar) pressure gauge to test port.
5. After installing pressure gauge to test port, start en-
gine and run at low idle speed. Check for any hydraulic
leakage from test connections and correct before pro-
ceeding with test.
6. Increase engine speed to high idle speed (3000
RPM). Make sure hydraulic oil is at normal operating
temperature by operating the machine under load for
approximately ten (10) minutes.
IMPORTANT: Do not allow circuit pressure to ex-
ceed 2500 PSI (172 bar).
IMPORTANT: While performing this test, hold lower
mow/raise lever in the raise position only long
enough to get a system pressure reading. Holding
the lever in raise for an extended period may dam-
age system components.
7. Make sure that reel engage/disengage switch is OFF
and then pull lower mow/raise lever rearward (raise po-
sition) to pressurize lift circuit. While holding lever rear-
ward, watch pressure gauge carefully. As the cutting
units raise fully and the lift relief valve lifts, system pres-
sure should be:
Approximately 2000 PSI (138 bar)
Reelmaster 5010- H
8. Once relief pressure has been determined, return
the lower mow/raise lever to the neutral position and
stop the engine.
9. If measured pressure is incorrect, remove solenoid
relief valve (SVRV) in lift control manifold and clean or
replace valve (see Lift Control Manifold Service in the
Service and Repairs section of this chapter). Also, if
pressure is low, check for restriction in gear pump suc-
tion hose. Internal lift cylinder leakage in one or more
cylinders would also cause low lift circuit pressure (see
Lift Cylinder Internal Leakage Test in this section). Gear
pump section (P1) could also be suspected of wear,
damage or inefficiency (see Gear Pump (P1) Flow Test
in this section).
10.After lift relief valve pressure testing is completed,
make sure that engine is stopped, then relieve hydraulic
system pressure (See Relieving Hydraulic System
Pressure in the General Information section of this
chapter). Disconnect pressure gauge from test port at
gear pump and install dust cap to test port.
11. Lower and secure operator seat.
2
1
st
1. 1 gear pump section
Page 4 - 43
Figure 40
2. Test port
Hydraulic System