Toro Groundsmaster 4100-D Service Manual page 81

Procedure for Counterbalance Pressure Test
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine under load for
approximately ten (10) minutes. Make sure the hydrau-
lic tank is full.
2. Park machine on a level surface with the cutting deck
lowered and off. Make sure engine is off and the parking
brake is engaged.
3. Remove controller cover to gain access to lift/lower
manifold (Fig. 30).
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.
4. Determine system charge pressure (see Traction
Circuit Charge Pressure in this section).
5. Connect a 1000 PSI (70 bar) pressure gauge to
counterbalance test port G2 on lift/lower manifold under
controller cover (Fig. 31).
6. After installing pressure gauge, start engine and run
at idle speed. Check for hydraulic leakage at pressure
gauge location and correct before proceeding with test.
7. Move throttle so engine is running at high idle speed
(2870 RPM) with no load on the system. Do not engage
the cutting deck.
GAUGE READING TO BE 220 PSI (15.2 bar) over
system charge pressure (e.g. if charge pressure is
250 PSI (17.2 bar), counterbalance pressure should
be 470 PSI (32.4 bar)).
8. Stop the engine and record test results.
9. Adjustment of the counterbalance valve can be per-
formed as follows:
NOTE: Do not remove the counterbalance valve from
the hydraulic manifold for adjustment.
A. Loosen lock nut on counterbalance valve (Fig.
31).
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/4110--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 lock nut to secure adjustment. After ad-
justment, recheck counterbalance pressure. Re-
adjust as needed.
10.When testing is completed, disconnect pressure
gauge from manifold test port. Install controller cover.
RIGHT
FRONT
1. Controller cover
2. Screw (2 used)
3. Flat washer (2 used)
2
1. Lift/lower manifold
2. Test port G2
3. Counterbalance valve
Page 4 - - 43
2
1
4
Figure 30
4. U- -nut (2 used)
5. Lift/lower manifold
5
4
3
Figure 31
4. Lock nut
5. Adjusting screw
Hydraulic System
3
5
1