Toro Groundsmaster 4100-D Service Manual page 85

Procedure for Counterbalance 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
decks lowered and off. Make sure engine is off and the
parking brake is engaged. Remove console cover.
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. Determine system charge pressure (see TEST NO.
1: Traction Circuit Charge Pressure in this chapter).
4. Connect a 1000 PSI gauge to counterbalance test
port on manifold under console (Fig. 36).
5. After installing pressure gauge, start engine and run
at idle speed. Check for hydraulic leakage and correct
before proceeding with test.
6. Operate the engine at full engine speed (2730 + 30
RPM) with no load on the system. Do not engage the
cutting decks.
GAUGE READING TO BE 225 PSI (17.3 bar) over
system charge pressure (e.g. if charge pressure is
250 PSI, counterbalance pressure should be 475
PSI).
7. Stop the engine. Record test results.
8. Adjustment of the counterbalance valve can be per-
formed as follows:
NOTE: Do not remove the valve from the hydraulic
manifold for adjustment.
A. Loosen locknut on counterbalance valve (Fig.
36).
B. To increase pressure setting, turn the adjust-
ment screw on the valve in a clockwise direction. A
1/8 turn on the screw will make a measurable change
in counterbalance pressure.
Groundsmaster 4100--D
C. To decrease pressure setting, turn the adjust-
ment screw on the valve in a counterclockwise direc-
tion. A 1/8 turn on the screw will make a measurable
change in counterbalance pressure.
D. Tighten locknut to secure adjustment. After ad-
justment, recheck counterbalance pressure. Re-
adjust as needed.
9. Disconnect pressure gauge from test port.
4
3
1
1. Counterbalance test port
2. Counterbalance valve
Page 4 - - 43
2
Figure 36
3. Locknut
4. Adjusting screw
Hydraulic System