SHIELD AS 9Y4570 - Caterpillar

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Tooling (B)
Test Preparation
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Install the steering frame lock. Refer to Operation and Maintenance Manual, "Steering Frame Lock".
Start the engine. Operate the dump body repeatedly until the temperature of the hydraulic oil is above 38°C (100°F).
Lower the body. Stop the engine. Test Procedure - Relief Valve (High Pressure)
Note: Ensure that the filters and the screens are clean before you test any pressures. Make sure that the oil is at operating temperature before you perform this test.Note: Before you perform any tests, visually inspect the entire hydraulic system for oil leaks and for damaged components.
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Manifold for the hoist cylinder lines
(5) Pressure tap
Remove the protective cover from pressure tap (5). Connect Tooling (B) to pressure tap (5). Note: Use the high-pressure gauge for this test procedure.
Start the engine.
Run the engine at high idle and move the hoist control to the RAISE position.
After the dump body is fully raised, observe the pressure gauge and hold the hoist control in the RAISE position. The high-pressure gauge reading is the relief valve pressure setting of high-pressure relief valve (1). Refer to Table 1 for the correct pressure setting.
If the pressure reading is not correct, continue with "Adjustment Procedure - Relief Valve (High Pressure)". Adjustment Procedure - Relief Valve (High Pressure)
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(1) High-pressure relief valve
(2) Low-pressure relief valve
(3) Hoist dual stage relief valve
(6) Locknut
(7) Retainer
Loosen locknut nut (6). Turn retainer (7) in order to adjust the setting of high-pressure relief valve (1). Turn retainer (7) clockwise in order to increase the pressure setting, and turn retainer (7) counterclockwise in order to decrease the pressure setting.
Tighten lock nut (6). Refer to Table 3 for the correct tightening torque.
Recheck the pressure setting.
Lower the dump body and stop the engine.
Remove the test equipment. Place the protective cover on the pressure tap. Test Preparation
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Install the steering frame lock. Refer to Operation and Maintenance Manual, "Steering Frame Lock".
Start the engine. Operate the dump body repeatedly until the temperature of the hydraulic oil is above 38°C (100°F).
Lower the body. Stop the engine.
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Manifold for the hoist cylinder lines
(8) Pressure tap
Remove the protective cover from pressure tap (8). Connect Tooling (B) to pressure tap (8). Note: Use the low-pressure gauge for this test in order to obtain an accurate reading.Test Procedure - Relief Valve (Low Pressure)
Start the engine.
Lower the body on the truck frame.
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Body position sensor secured in the RAISE position
(9) Body position sensor Note: The body position sensor must be in the RAISE position before low-pressure relief valve (2) can be measured. If the body position sensor is in the LOWER position, the Power Train/Chassis (ECM) will keep the hoist control valve in the SNUB position. Low-pressure relief valve (2) cannot be measured in this position.
Disconnect the return spring from the lever on body position sensor (9). Rotate the lever on the body position sensor to the RAISE position. Secure the lever in this position, as shown.
Move the hoist control to the HOLD position. Run the engine at high idle and move the hoist control to the