TM 5-2420-231-23-1
0064
Table 1. All Hydraulic Functions Move Slowly or Have No Power - Continued.
064
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Test Step 6. Test Backhoe Load
All Hydraulic Functions
Sense Relief Valve.
Move Slowly or Have No
Power - Continued
Perform backhoe load sense relief
Backhoe Load Sense Relief Valve
valve pressure check (WP 0086).
Pressure 3,000 to 3,100 psi (20,684 to
21,373 kPa) - Proceed to Test Step 7.
Backhoe Load Sense Relief Valve
Pressure Not Within Specification -
Perform Flowmeter Disconnect
Procedure (WP 0086).
Replace backhoe control valve
assembly (WP 0263).
Proceed to Test Step 8.
Test Step 7. Test Pump Efficiency.
1. Perform large hydraulic oil pump
Pump Efficiency Greater Than 70
efficiency reading (WP 0086).
Percent - Proceed to step 2.
Pump Efficiency Less Than 70
Percent - Perform Flowmeter
Disconnect Procedure (WP 0086).
Replace hydraulic oil pump (WP 0230).
Proceed to Test Step 8.
2. Perform large and small hydraulic
Pump Efficiency Greater Than 70
Percent - Perform Flowmeter
oil pump efficiency reading
Disconnect Procedure (WP 0086).
Proceed to Test Step 8.
Pump Efficiency Less Than 70
Percent - Perform Flowmeter
Disconnect Procedure (WP 0086).
Replace hydraulic oil pump (WP 0230).
Proceed to Test Step 8.
Test Step 8. Verify That Symptom Is
Resolved.
1. Operate loader lift, clamshell, and Loader Lift, Clamshell, and Bucket
bucket (TM 5-2420-231-10). Moni- Operate Slowly or Do Not Operate -
tor and record machine operation. Repeat troubleshooting from the
beginning.
Loader Lift, Clamshell, and Bucket
Operate Normally - Proceed to step 2.
2. Enable pilot control switch (TM 5-
2420-231-10).
3. Operate left stabilizer (TM 5-2420-
Left Stabilizer Operates Slowly or
231-10) and observe and take
Does Not Operate - Repeat
note of operation.
troubleshooting from the beginning.
Left Stabilizer Operates Normally -
Proceed to step 4.
0064-5
