Jacobsen AR3, Техническое руководство по ремонту

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6-28 4181384 First Edition
HYDRAULICS
6
Field Test Procedures
Lift Cylinder Leakage Test
See Figures 6-17 and 6-18.
!
WARNING
1. Start engine. Operate hydraulic system until oil
temperature is at 120—150°F (49—65°C).
2. Park the mower safely. (See “Park Mower Safely” on
page 1-6.)
3. Raise cutting units and stop engine.
4. Support cutting unit lift arms.
.
Figure 6-17
NOTE
Figure 6-24 shows rear lift arm cylinder. Procedure is
similar for front lift cylinders.
5. Remove hose (1) from lift cylinder rod end fitting (2).
6. Install plug in hose (1).
7. Install cap on lift cylinder fitting (2).
8. Remove support from cutting unit lift arm.
After 15 minutes, does cutting unit drift down?
YES Cylinder is bypassing oil. Replace lift
cylinder. (See “Lift Cylinder” on page 6-54.)
NO Repeat the test for all of the lift cylinders. If
all cylinders pass test, the problem may be in
the lift valve. Proceed to step 9.
9. Connect hose (1) to lift cylinder fitting (2).
Figure 6-18
10. Remove check valve (3) from the lift valve body (5).
11. Clean and inspect check valve for damage. Replace
as necessary.
12. If lift cylinders continue to drift down, remove lift
solenoid valve (4) from lift valve body (5).
13. Clean and inspect lift solenoid valve for damage.
Replace as necessary. (See “Solenoid Test” on
page 4-68.)
Power Steering Circuit Test
The purpose of this test is to determine if the steering
cylinder and the steering valve are operating properly.
NOTE
Before performing the test, check the steering system for
mechanical binding or damage that may effect the
steering.
1. Operate the machine until hydraulic oil reaches
operating temperature,120—150°F (49—65°C).
2. With the engine running, turn the steering wheel all
the way right, and then all the way left.
Does the steering wheel continue to turn after full
left or right movement of the steering cylinder?
YES Proceed to step 3.
NO Steering system is not faulty.
The hydraulic system is under pressure, and the
oil will be hot.
• Always relieve pressure in the hydraulic
system before performing service.
• Failure to follow appropriate safety
precautions may result in death or serious
injury.
TN1120
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TN1302
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