PROBLEM: Percent of flow loss for Tests 15 through
17 is more than the percent shown in
Chart B.
PROBABLE REASON:
A. Bad large pump, Chart C2.
B. Leakage in elevator motor.
C. Leakage in elevator control valve.
D. Leakage in relief valve.
E. Leakage in speed control valve.
RECOMMENDATION FOR ACTION:
Do the Elevator Large Pump Test, Chart C2. If
the extra flow loss is not caused by a bad pump, do the
Blocked Elevator Motor Tests 38, 39, and 40. If the extra
flow loss is not caused by large amount of leakage, do
the leakage Tests 40, 54, 55, and 56. Repair or replace
parts as necessary.
PUMP TEST (Charts C1, C2, C3)
These tests are used to find the efficiency of the
hydraulic pumps. The tests are the same for all pumps
and/or pump sections. Analysis of the system data
(Charts A and B) will give an indication of which pumps
or pump sections must be tested. See the respective
schematic or illustration in the Tee Test Insert for the
correct tee and blocking locations. The locations are as
follows:
Chart C1: Scraper and Steering Pump (Large
Section).
Tee location: The plug on the supply line near
the implement control valve.
Blocking location: Between the supply line and
the implement control valve.
Chart C2: Elevator Pump (Large Section).
NOTE: Speed Control Valve must be in LOW SPEED
position during this test.
Tee location: The plug on the supply line near
the elevator control valve.
Blocking locations:
1.
Between the supply line and elevator control valve.
2. Between the elevator relief valve and the hydraulic
tank.
Chart C3: Elevator Pump (Large and Small Section).
WARNING: Speed control valve must be in
HIGH SPEED position during this test.
Tee location: The plug on the supply line near
the elevator control valve.
Blocking locations:
1. Between the elevator control valve and the supply
line.
2. Between the elevator speed control valve and the
hydraulic tank.
3. Between the elevator relief valve and the hydraulic
tank.
WARNING: Installation of the Blocking Plate
Assemblies keeps oil from going through the
system. All pump flow goes through the flow
meter. Open the manual load valve fully,
then start the diesel engine. The main relief valve is not
part of the circuit for the pump test. If the pressure gets
too high, it is possible to cause injury to personnel or
damage to equipment.
Test 22: Pump Flow at Low Pressure (Test rpm)
1. Open the manual load valve fully.
2. Start the diesel engine.
3. Run the engine at test rpm.
4. Slowly close the manual load valve to get 100 psi
pressure.
5. Write down the oil temperature and the flow rate
(gpm).
Test 23: Pump Flow at High Pressure (Test rpm)
1. Run the engine at test rpm.
2. Slowly close the load valve to get 1000 psi pressure.
3. Write down the oil temperature and flow rate (gpm).
Test 24: Pump Flow at Low Pressure (/2 Test rpm)
1. Run the engine at l/ Test rpm.
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