9/8/2014 8:09 AM
Here's a few more tests to try. Might point you to the hose with the issue.
TESTS AND ADJUSTMENTS
STEERING SYSTEM TEST
Reason:
To check steering control unit and steering cylinder
operation and check for internal leakage.
Tools:
• Torque wrench
• Caps for hydraulic lines
Procedure:
1. Run the tractor until the hydraulic fluid is at
operating temperature.
2. Turn the steering wheel to the full right position.
Apply 6.8 N•m (60 lb in.) constant torque to the
steering wheel retaining nut, and count the
steering wheel rotations in one minute.
3. Repeat the procedure turning the steering wheel to
the full left position.
4. Stop engine.
Results:
• If the rotation in left or right hand direction exceeds
5 rotations in one minute, the steering system has
internal leakage. To determine whether it's the
SCU or cylinder that is leaking, proceed as follows:
Procedure:
1. Label and remove both left and right hydraulic
hoses at the steering cylinder.
2. Cap the ends of both hoses.
3. Repeat the SCU test.
Results:
• If the rotation speed is now below 5 rotations in one
minute, replace the steering cylinder.
• If the rotation speed remains above 5 rotations in
one minute, replace the SCU.
STEERING PRESSURE CHECK
Reason:
To ensure that steering pump pressure is maintained at
correct level for steering without causing damage to the
system, and to determine if hydraulic pump is worn.
Equipment:
• JT03375 - Adapter Fitting (7/16-20 M 37° X 9/16-18
M ORFS)
• JT03117 - 0-14000 kPa (0-2000 psi) Pressure
Gauge
• JT03017 Hose w/Quick Disconnect Fitting
Procedure:
1. Park tractor on a level surface and set park brake.
2. Shift transmission to NEUTRAL.
IMPORTANT: Make sure to relieve system pressure
before loosening any system lines or hoses.
3. Cycle all controls to relieve any pressure that may
be in the hydraulic system.
4. Remove hydraulic hose on left side of steering
cylinder.
5. Attach gauge to left steering hose.
NOTE: Turning steering wheel to the right will cause
hydraulic oil to leak out of disconnected
cylinder port. Turn wheel only to left when
performing test.
6. Start engine and run at high idle.
7. Turn steering wheel to the left. While turning wheel,
check pressure reading on gauge.
Specifications:
Pressure . . . . . . .10342 kPa ± 10% (1500 psi ± 10%)
Results:
• No pressure: Steering hoses may be incorrectly
connected to the SCU. Check hose connections.
• Pressure too low: Relief valve in SCU may be
stuck open or defective; perform steering system
test, (See "STEERING SYSTEM TEST" on
page 9), or gear pump may be worn; disassemble
and inspect pump. (See "Disassembly and
Inspection:" on page34 in the Hydraulics Section).
• Pressure too high: Relief valve in SCU may be
clogged or defective.
Bret Hart
Equipment Manager
Turning Stone Resort