Jacobsen SLF 1880, Техническое руководство по ремонту

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8G-46
FLOW TESTS
Follow the directions for each test carefully. The
hydraulic oil must be at normal operating temperature
before performing the test to ensure proper test results.
Read and understand the flow meter directions and
instructions before attempting to test the hydraulic sys-
tem (Figure 8G-3).
Figure 8G-3. Flow Meter and Hydraulic System
CHARGE PUMP FLOW TEST
The hydrostatic charge pump supplies oil flow to the
steering unit and hydrostatic traction pump closed loop
circuit.
1. Shut off the engine and remove the ignition key.
2. Connect the flow meter IN port to the charge
pump outlet fitting on the right side of the traction
pump (Figure 8G-4).
3. Connect flow meter OUT port to the charge pump
outlet hose (Figure 8G-4).
4. Open the tester load valve, set the parking brake,
start the engine, and advance the engine speed to
full throttle.
5. Record the charge pump no load flow indication
C) on Charge Circuit Test Record (Figure 8G-12).
6. Slowly close tester load valve until a reading of
850 psi (5860 kPa) is obtained,
7. Record loaded flow indication D) on Charge Cir-
cuit Test Record (Figure 8G-12).
8. Subtract flow indication D) from flow indication C)
on the Charge Circuit Test Record. The result is
the charge pump leakage (Figure 8G-12).
Conclusion
• If leakage is less than ½ gpm (1.9 lpm), pump is not
at fault.
• If leakage is ½ to 1 gpm (1.9 to 3.8 lpm), pump and/
or steering circuit relief valve is marginal.
• If leakage is 1 gpm (3.8 lpm) charge pump and/or
steering circuit relief may be faulty.
9. Slowly close tester load valve until flow is 0.0 gpm/
lpm and pressure stays constant. Record the
steering relief valve pressure Indication
B) on the
Charge Circuit Test Record which should be 1160
psi (7998 kPa) +/- 10% (Figure 8G-12).
Conclusion
• If relief pressure is within range, relief and pump are
not at fault, proceed with Step 9.
Load
Valve
Hydraulic
System
Flow Meter
CAUTION
Do not exceed 1250psi (8618 kPa) during the follow-
ing test.
!