Toro 30821 Service Manual page 89

Procedure for Logic (Counterbalance) Valve (LC1)
Pressure Test:
NOTE: If the counterbalance system is functioning, the
machine should normally settle slightly when the engine
is started.
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately 10
minutes.
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.
3. Read Precautions for Hydraulic Testing.
4. Remove plug from hydraulic manifold port (G2) (Fig.
65 and 66).
5. Install test gauge with hydraulic hose attached to
port (G2).
CAUTION
Keep away from decks during test to prevent per-
sonal injury from the cutting blades.
6. Start engine and move throttle to full speed (3050 +
50 RPM). Do not engage or raise the cutting units.
7. The standard counterbalance pressure should be
250 PSI with a range of 180 to 300 psi. Adjustment of the
Logic valve (LC1) can be performed as follows:
Note: Do not remove the Logic valve from the hydrau-
lic manifold for adjustment.
A. Remove hex cap from logic valve (Fig. 67).
B. Loosen locknut.
C. To increase pressure setting, turn the adjust-
ment shaft on the valve in a clockwise direction. A 1/8
turn on the shaft will make a measurable change in
counterbalance pressure.
D. To decrease pressure setting, turn the adjust-
ment shaft on the valve in a counterclockwise direc-
tion. A 1/8 turn on the shaft will make a measurable
change in counterbalance pressure.
E. Tighten locknut. Check counterbalance pressure
and readjust as needed.
F. Replace hex cap to Logic valve (LC1).
Groundsmaster 3500- D
8. Lower cutting units. Shut off engine.
9. Disconnect test gauge with hose from manifold
block. Reconnect plug to the hydraulic manifold port
(G2).
1. Hydraulic manifold
1. Hydraulic manifold
3
2
1
1. Manifold assembly
2. Logic valve (LC1)
Page 4 - 49
1
2
Figure 65
2. Manifold port (G2)
1
2
Figure 66
2. Manifold port (G2)
Figure 67
3. Hex cap
Hydraulic System (Rev. G)