Toro Reelmaster 3550-D Service Manual page 95

Steering/Lift Circuit Testing − Steering Relief Valve
Pressure Test:
The relief valve for the steering and lift circuits (RM
3550−D), or for the steering circuit only (RM
3555−D/3575−D) is integrated into the steering control
valve. If both steering and lift operations (RM 3550−D),
or just the steering circuit (RM 3555−D/3575−D) per-
form poorly, perform the relief valve pressure test and
gear pump (P2) flow test (see Steering/Lift Circuit −
Gear Pump (P2) Flow Test in this chapter).
1. Park machine on a level surface with the cutting units
lowered and reel engage/disengage switch in the disen-
gage position. Make sure engine is off and the parking
brake is engaged.
2. Read Precautions for Hydraulic Testing in this
chapter.
3. Install a T−connector with a pressure gauge be-
tween the gear pump and the hydraulic hose connection
on gear pump (P2) (Fig. 39).
4. Make sure steering wheel is positioned so the rear
wheel points directly ahead.
5. Start the engine, and move throttle to full speed
(3220 + 50 RPM).
6. Make sure hydraulic fluid is at normal operating tem-
perature by operating the machine for approximately 10
minutes.
7. Watch pressure gauge carefully while turning the
steering wheel completely in one direction and holding.
CAUTION
Do not allow pressure to exceed 1500 PSI. Hold
steering wheel at full lock only long enough to
get a system pressure reading. Holding the
steering wheel against the stop for an ex-
tended period may damage the steering con-
trol valve.
Reelmaster 3550−D/3555−D/3575−D
RIGHT
FRONT
1. Gear pump assembly
8. System pressure should reach 940 to 1015 PSI (65
to 70 Bar) as the relief valve opens.
9. Return steering wheel to the center position and shut
off engine.
10.If specification is not met, repair or replace steering
control valve.
11. Disconnect T−connector with pressure gauge and
reconnect hydraulic hose to gear pump.
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2
P2
P1
Figure 39
2. Hydraulic hose
Hydraulic System
1