Toro 30874 Lawn Mower User Manual


 
Groundsmaster 4500--D/4700--D Hydraulic SystemPage 4 -- 65
The steering cylinder internal leakage test should be
performed if a steering p roblem is identified. This test
will determine if the steering cylinder is faulty.
Procedure for Steering Cylinder Internal Leakage
Test
NOTE: Steering circuit operation will be affected by
rear tire pressure, binding of steering cylinder, extra
weight on the vehicle and/or bindingof rear axlesteering
components. Make sure that these items are checked
before proceeding with steering cylinder internal leak-
age test.
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.
1. Park machine on a level surface with the cutting
decks lowered and off. Make sure hydraulic oil is at nor-
mal operating temperature, engine is off and the parking
brake is applied.
2. Turn the steering wheel for a right turn so that the
steering cylinder rod is fully extended.
3. Thoroughlyclean thearea aroundthe hydraulichose
at the rod end of the steering cylinder.
4. Place a drain pan under the steering cylinder. Re-
move hydraulic hose from the fitting on the rodend of the
steering cylinder. Install a steel plug in the disconnected
hose. Leave cylinder fitting o pen.
5. Remove all hydraulic oil from drain pan. Make sure
that empty drain pan remains under the open fitting of
the steering cylinder.
6. With the engine off, turn the steering wheel for a right
turn. Observe the open fitting on the extended steering
cylinder as the steering wheel is turned. If oil comes out
of the fitting while turning the steering wheel, the steer-
ing cylinder has internal leakage and must be repaired
(see Steering Cylinder and Steering Cylinder Service in
the Service and Repairs section of this chapter). Check
drain pan for any evidence of oil that would indicate cyl-
inder leakage.
7. If a steering problem exists and the steering cylinder
tested acceptably, the steering control valve requires
service (see Steering Control Valve and Steering Con-
trol Valve Service in the Service and Repairs section of
this chapter).
8. After testing is completed, remove plug from the hy-
draulic hose. Connect hose to the steering cylinder fit-
ting.
9. Check oil level in hydraulic reservoir and adjust if
needed.
Hydraulic
System