TM 5-3805-260-24
Tee location for Tests 34 through 38 are at the
plug on the supply line elbow at the scraper control valve
or pump. Blocking locations are explained at the
beginning for each test. See schematics and illustrations
for the specific machine being tested.
NOTE: It is important that the tee block and blocking
plate assemblies be installed in the exact position shown
to get the correct test results. Remove all blocking
plates not for the specific test being made.
For All Blocked Circuit Tests
1. Put control levers in HOLD position.
2. Open the manual load valve fully.
3. Start the diesel engine.
Blocked Circuit Test
Tee location for Tests 33 through 37 is the plug
on the supply line near the scraper control valve.
Test 33: System Oil Temperature
1. Put the ejector control lever in the FOR- WARD
position.
2. Run the engine at any rpm with the system pressure
at 0 to 100 psi.
3. Write down the oil temperature.
Tests 34 through 37: Leakage Rate
1. Block the circuit line for the ejector and bowl circuits
at the control valve.
2. With the manual load valve fully open, move the
ejector control lever to the FORWARD (OPEN)
position.
3. Run the engine at test rpm.
4. Slowly close the manual load valve to get 1000 psi
pressure.
5. Write down the flow rate (gpm).
6. Do this procedure again for ejector return, bowl raise,
and bowl lower.
Tests 38 through 40: Leakage Rate
Tee location: The plug on the supply line near
the
elevator
control
valve.
Blocking location: The circuit line for the elevator
circuit at the control valve.
1. With the manual load valve fully open, move the
elevator control lever to the FORWARD position.
2. Slowly close the manual load valve to get 1000 psi.
3. Write down the flow rate (gpm).
4. Repeat this procedure for elevator reverse and
elevator fast forward.
Test 41: System Oil Temperature
1. Put the ejector control lever in FORWARD (OPEN)
position.
2. Run the engine at any rpm with the system pressure
at 0 to 100 psi.
3. Write down the oil temperature.
Find the leakage rate’ of the circuit and the
leakage rate of the control valves. Use the test
information from the System Tests, Pump Test and
Blocked Circuit Tests.
Example 1: Find the leakage rates of the ejector
circuit in the FORWARD position.
Test 23;
Chart C1: Flow rate of the pump only.
Test 34:
Flow of pump and control valve.
Test 4:
Flow rate of pump, control valve and
circuit.
The system components tested in Tests 34 and
23, Chart C1 are the same except for the control valve.
Then the difference in flow rates must be the leakage in
the control valve in the circuit (take the test information
for Test 34 away from the test information for Test 23,
Chart C1).
The system components tested in Tests 34 and
4 are the same except for the cylinders, and floor
cylinder check valve (ejector cylinder check valve). Then
the difference in flow rates must be the leakage in the
cylinders, and floor cylinder check valve (ejector cylinder
check valve) (take the test information for Test 4 away
from the test information for Test 34).
Example 2: Find the leakage rates of the eleva-
tor circuit in the FORWARD FAST position.
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