Toro Groundsmaster 4500-D Service Manual page 83

Procedure for Counterbalance (RV1) 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 counterbalance test
port on power down and traction assist manifold under
operator's seat (Fig. 44).
4. Start the engine and put throttle at full engine speed
(2800 + 50 RPM) with no load on the system. Do not en-
gage the cutting units.
GAUGE READING TO BE 600 to 640 PSI.
NOTE: Counterbalance pressure setting toward the
higher specification (640 PSI) will improve traction on
slopes. Counterbalance pressure setting toward the
lower specification (600 PSI) improves quality of cut.
5. Adjustment of the counterbalance valve can be per-
formed as follows:
NOTE: Do not remove the valve from the hydraulic
manifold for adjustment.
A. To increase pressure setting, turn the adjusting
dial on the counterbalance valve in a clockwise di-
rection. A 1/8 turn on the dial will make a measurable
change in counterbalance pressure (Fig. 45).
B. To decrease pressure setting, turn the adjusting
dial on the counterbalance valve in a counterclock-
wise direction. A 1/8 turn on the dial will make a mea-
surable change in counterbalance pressure (Fig.
45).
C. Recheck counterbalance pressure and readjust
as needed.
Groundsmaster 4500--D/4700--D
2
1. Traction assist manifold (GM 4500- -D shown)
2. Counterbalance test port
1
1. GM 4500- -D traction assist manifold
2. GM 4700- -D traction assist manifold
3. Counterbalance valve (RV1)
Page 4 - - 45
1
Figure 44
3
3
2
Figure 45
Hydraulic System (Rev. A)