Toro Groundsmaster 4000-D Service Manual page 79

Procedure for Rear Traction Circuit (RV5) Relief
Pressure Test
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately 10
minutes. Make sure the hydraulic tank is full.
2. Park machine on a level surface with the cutting units
lowered and off. Make sure engine is off and the parking
brake is engaged.
CAUTION
Prevent personal injury and/or damage to equip-
ment. Read all WARNINGS, CAUTIONS, and Pre-
cautions for Hydraulic Testing at the beginning
of this section.
3. Connect a 1000 PSI gauge to test port on 2WD/4WD
control manifold under radiator (Fig. 33).
4. Start the engine and put throttle at full engine speed
(2730 + 30 RPM).
5. Operate the machine in 4WD with the cutting units
lowered. Drive down a slope in a forward direction, de-
crease pressure on the traction pedal, and monitor the
pressure gauge. Pressure should increase until the re-
lief valve lifts.
GAUGE READING TO BE 750 PSI (approximate).
6. Relief valve (RV5) is located on the lower, front side
of the 2WD/4WD control manifold (Fig. 34). Adjustment
of the relief valve can be performed as follows:
NOTE: Do not remove the valve from the hydraulic
manifold for adjustment.
A. To increase relief pressure setting, remove cap
on relief valve and turn the adjustment socket on the
relief valve in a clockwise direction. A 1/8 turn on the
socket will make a measurable change in relief pres-
sure (Fig. 35).
B. To decrease pressure setting, remove cap on re-
lief valve and turn the adjustment socket on the relief
valve in a counterclockwise direction. A 1/8 turn on
the socket will make a measurable change in relief
pressure (Fig. 35).
C. Recheck relief pressure and readjust as needed.
Groundsmaster 4000--D
1. 2WD/4WD control manifold
2. Relief valve test port
1
1. Manifold: lower side
1. Relief valve cap
Page 4 - - 45
1
2
Figure 33
2
Figure 34
2. Relief valve (RV5)
1
2
Figure 35
2. Adjustment socket
Hydraulic System (Rev. B)