TM 5-2420-231-23-1
0075
Table 1. Backhoe Dipper Does Not Operate Correctly - Continued.
075
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Backhoe Dipper Does Not
Test Step 4. Check Pilot Control
Operate Correctly -
Pressure.
Continued
While operating backhoe dipper, extend
Pilot Control Pressure 350 to 550 psi
and retract (TM 5-2420-231-10) while
- Proceed to Test Step 5.
testing pilot control pressure (WP
Pilot Control Pressure Less Than 350
psi - Disconnect hose and pressure
gauge.
Replace pilot control valve assembly
(WP 0264).
Proceed to Test Step 6.
Test Step 5. Check Joystick Control.
1. Perform pilot control valve test
Any Pilot Control Flow Greater Than
1 gpm - Perform Flowmeter Disconnect
Procedure (WP 0086).
Replace backhoe control valve
assembly (WP 0263).
Proceed to Test Step 6.
Any Pilot Control Flow Less Than 1
gpm - Perform Flowmeter Disconnect
Procedure (WP 0086).
Proceed to step 2.
2. Push control pattern switch to Pat-
tern 2 (TM 5-2420-231-10).
3. Operate backhoe dipper (TM 5-
Backhoe Dipper Cylinder Operates
Normally - Replace left-side joystick
2420-231-10). Monitor and record
machine operation.
control valve assembly (WP 0266).
Proceed to Test Step 6.
Backhoe Dipper Will Not Operate -
Replace backhoe control valve
assembly (WP 0263).
Proceed to Test Step 6.
Test Step 6. Verify That Symptom Is
Resolved.
Operate backhoe dipper (TM 5-2420-
Backhoe Dipper Cylinder Operates
231-10). Monitor and record machine
Normally - Troubleshooting complete.
operation.
Backhoe Dipper Cylinder Operates
Slowly or Will Not Operate- Repeat
troubleshooting from the beginning.
END OF WORK PACKAGE
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