Toro Reelmaster 7000-D Service Manual page 141

Steering/Lift Circuit − Steering Relief Pressure Test
Unit steering performance will be affected by incorrect
rear tire pressure, binding in the hydraulic steering cylin-
der, extra weight on the vehicle, and/or binding of the
steering fork assembly. Make sure that these conditions
are checked and functioning properly before proceeding
with any steering system hydraulic testing.
The relief valve for the steering circuit is integrated into
the steering control valve. If steering system performs
poorly, perform the steering circuit relief pressure test.
If both steering and lift operations perform poorly, per-
form the flow test on gear pump section P4 (see Gear
Pump Flow Test in this chapter).
Special Equipment Required:
S Pressure Gauge − 5000 PSI (350 bar) with hose
S Hydraulic Cap − 11/16 − 16
S Phototach (non−contact tachometer)
1. Park machine on a level surface with the cutting units
lowered and the reel enable/disable switch in the DIS-
ABLE position. 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.
2. Thoroughly clean junction of hydraulic hose and
steering cylinder fitting at the barrel end of the steering
cylinder (Fig. 40). Disconnect hose from fitting in barrel
end of steering cylinder.
3. Install 5000 PSI (350 bar) pressure gauge with hy-
draulic hose attached to disconnected hose. Install a hy-
draulic cap on steering cylinder fitting to prevent any
leakage from cylinder.
4. Start engine and run at low idle speed. Check for hy-
draulic leaks at tester connections and make correc-
tions if necessary before proceeding with test.
5. Set throttle to high speed.
A. Use the InfoCenter display to verify engine RPM
on units with Yanmar diesel engines (2850 RPM).
B. Use a phototach to verify engine RPM on units
with Kubota diesel engines (2850 +50/−120 RPM).
6. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately ten
(10) minutes.
Reelmaster 7000−D
2
1. Steering cylinder
2. Barrel end hose
IMPORTANT: While testing, rotate steering wheel
only long enough to get a system relief pressure
reading. Holding the steering circuit at relief pres-
sure for an extended period may damage the steer-
ing control valve.
7. Turn steering wheel to the right while monitoring the
pressure gauge. When steering circuit pressure reach-
es the relief pressure setting, pressure should stabilize
briefly and then may continue to increase. The steering
circuit relief pressure is the gauge reading when pres-
sure stabilizes.
GAUGE READING TO BE:
1015 TO 1088 PSI (70 to 75 bar)
8. Stop the engine. Record test results.
9. If steering relief pressure is incorrect, inspect steer-
ing relief valve located in the steering control valve (see
Steering Control Valve Service in the Service and Re-
pairs section of this chapter). If relief valve is operating
properly and if lift/lower problems also exist, gear pump
P4 should be suspected of wear or damage. If steering
wheel continues to turn at end of cylinder travel (with
lower than normal effort), steering cylinder or steering
control valve may be worn or damaged.
10.When testing is complete, relieve steering circuit
pressure and remove pressure gauge from hydraulic
hose. Remove steel cap from steering cylinder fitting
and connect hydraulic hose to steering cylinder.
11. Start engine and run at low idle speed. Check for hy-
draulic leaks at steering cylinder and make corrections
if necessary before returning machine to service.
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1
FRONT
3 4
RIGHT
Figure 40
3. Barrel end fitting
4. Rear axle
Hydraulic System