814F Wheel Tractor, 815F Soil Compactor and 816F Landfill Compactor Hydraulic System Caterpillar

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Personal injury or death can result from sudden machine movement. Sudden movement of the machine can cause injury to persons on or near the machine. To prevent injury or death, make sure that the area around the machine is clear of personnel and obstructions before operating the machine.

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Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.

The following procedure should be used in order to determine if there is a problem with the implement pump. Pump performance should be checked if the machine has slow implement movement or low digging power.

Machine Preparation

1. Move the machine to a smooth, level surface. Move away from working machines and personnel.

2. Allow only one operator on the machine. Keep all personnel away from the machine or in the view of the operator.

3. Lower the blade to the ground.

4. Ensure that the transmission direction control switch is in the NEUTRAL position.

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Illustration 1	g00888772

5. Install the steering frame lock.

6. Engage the parking brake.

Performance Test

Stall Test

The torque converter stall test is designed to test the engine, the torque converter, the drive train and the brake system as a unit. The torque converter output is stalled while the engine is operated at full throttle. The speed of the engine at torque converter stall indicates whether the engine and the transmission are operating correctly under full load.

If the engine speed is lower than the normal given speed or if the engine speed is higher than the normal given speed, this indicates that there is a problem in the engine or in the transmission. If testing shows correct engine performance but the torque converter stall speed is not correct, the problem is in the torque converter or in the transmission.

Reference: To check the performance of the Caterpillar 3176C Engine, refer to the following service literature: Specifications, SENR9527, "3176C and 3196 Engines for Caterpillar Built Machines" and Systems Operation, Testing and Adjusting, SENR9528, "3176C and 3196 Engines for Caterpillar Built Machines".

Note: The stall speeds are dependent on the type and quality of the diesel fuel. Since the stall speeds are dependent on the type of fuel, water content of the fuel, and other additives, the diesel fuel should meet Caterpillar specifications. For more information about fuel specifications, refer to the Service Manual module Operations and Maintenance Manual, SEBU6250, "Caterpillar Machine Fluids Recommendations" for the machine that is being serviced.

The service brakes must be applied when tests are performed. Make sure that the service brakes are fully operational before you perform any tests. Make sure that the transmission oil is at the normal operating temperature of 76 to 112°C (168 to 234°F) when tests are performed.

The drive wheels must not turn during the torque converter stall test. Place the machine against a solid, stationary object such as a loading dock. Engage the parking brake.

The transmission auto/manual switch (if equipped) must be in the MANUAL position in order to prevent any unexpected shifts during the stall test.

1. Engage the parking brake and shift the transmission to the NEUTRAL position.

2. Start the engine. Warm the transmission oil to normal operating temperature of approximately 76 to 112°C (168 to 234°F).

3. Fully depress the right side service brake pedal. Hold the right service brake pedal in the depressed position for the duration of the test. Ensure that the parking brake is applied.

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NOTICE
To ensure that the transmission oil does not overheat, do not keep the torque converter in a full stall condition for more than 30 seconds. After the torque converter stall test, reduce the engine speed to low idle. In order to cool the oil, move the transmission control to the NEUTRAL position and run the engine between 1200 rpm and 1500 rpm.

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Illustration 2	g00888817
Dash Panel (1) Quad Gauge Electronic Module. (2) Speedometer/Tachometer Module. (3) Main Display Module.

4. Shift the transmission direction and speed control lever to the FOURTH SPEED FORWARD position for the 814F Wheel Tractor. Shift the transmission direction and speed control lever to the THIRD SPEED FORWARD position for the 815F Soil Compactor. Shift the transmission direction and speed control lever to the SECOND SPEED FORWARD position for the 816F Landfill Compactor. Fully depress the accelerator pedal. Allow the engine rpm to stabilize. Then, observe the tachometer and record the result.

The correct stall speed for the 814F Wheel Tractor, the 815F Soil Compactor, and the 816F Landfill Compactor is 2090 ± 65 rpm.

Stall speeds that are low indicate incorrect engine performance. Stall speeds that are high indicate incorrect transmission performance or incorrect performance of the torque converter. If you must repeat the test, keep the transmission in neutral and wait for two minutes between tests.

Reference: For additional information about the Caterpillar Monitoring System, refer to Service Manual, SENR1394, "Caterpillar Monitoring System".

Reference: For additional information about the Caterpillar Monitoring System, refer to the Service Manual module Systems Operation, "Caterpillar Monitoring System" for the machine that is being serviced.

Flow Test

Illustration 3	g00889228
Three-Section Vane Pump (4) Pilot pump section. (5) Implement pump section. (6) Steering pump section.

The hydraulic pump on the 814F Wheel Tractor, the 815F Soil Compactor, and the 816F Landfill Compactor is a three-section vane pump. Steering section (6) of the pump supplies oil flow for the hydraulic steering system. Implement pump section (5) supplies oil flow for the hydraulic implement system. The steering section (6) supplies oil flow to the steering system.

Measuring the oil flow can provide an indication of the condition of the pump. An inadequate amount of oil flow from the vane pump indicates that there is excessive internal leakage in the pump. This can be caused by wear or damage of the pump components. This test will check the ability of implement pump (5) to supply the proper amount of oil flow to the main hydraulic system.

The vane pump is mounted on the torque converter under the cab of the machine.

1. Start the engine. Warm the hydraulic oil to the normal operating temperature.

2. Turn the engine start switch to the OFF position.

3. Release the pressure from the hydraulic system.

   Reference: For more information about releasing the hydraulic pressure, refer to the Service Manual module Testing and Adjusting, "System Pressure - Release" for the machine that is being serviced.

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Illustration 4	g00885819
View of the Hydraulic Lines from the Left Side of the Machine (7) Front frame. (8) Main control valve. (9) Main pressure hose from the implement pump. (10) Return hose to the hydraulic tank. (11) Hydraulic tank. (12) Implement pump.

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Illustration 5	g00885970
4C-9910 Portable Hydraulic Tester (13) Inlet connection. (14) Readout for the flow rate. (15) Load valve. (16) Pressure gauge. (17) Outlet connection.

4. Mark the hose assemblies with the proper fittings on the main control valve. Remove hose assembly (9) from main control valve (8). Connect the end of hose assembly (9) to inlet (13) of 4C-9910 Portable Hydraulic Tester. Disconnect hose assembly (10) from main control valve (8). Connect hose (10) to outlet (17) of 4C-9910 Portable Hydraulic Tester .

   Note: Before starting the engine, open loading valve (15) counterclockwise in order to reduce the load pressure. The loading valve must not be adjusted above 15500 kPa (2250 psi). Setting the pressure with loading valve (15) above 15500 kPa (2250 psi) will probably damage the implement pump.

   Reference: For information about operating the 4C-9910 Portable Hydraulic Tester, refer to the Operation Manual, NEHS0565, "Portable Hydraulic Tester".

5. Install a 6V-9833 Cap Assembly on each of the fittings on the main control valve.

6. Start the engine.

7. Set the engine speed at high idle. High idle is approximately 2270 rpm. The rate of flow for the 814F Wheel Tractor and the 816F Landfill Compactor with the hydraulic pressure at 6900 kPa (1000 psi) should be approximately 120 L/min (31.7 US gpm). The rate of flow for the 815F Soil Compactor with the hydraulic pressure at 6900 kPa (1000 psi) should be approximately 87 L/min (23 US gpm).

8. Set the engine speed at half speed. Half speed is approximately 1135 rpm. The rate of flow for the 814F Wheel Tractor and the 816F Landfill Compactor with the hydraulic pressure at 6900 kPa (1000 psi) should be approximately 54 L/min (14.3 US gpm). The rate of flow for the 815F Soil Compactorwith the hydraulic pressure at 6900 kPa (1000 psi) should be approximately 38 L/min (10 US gpm).

   Reference: For more information about the implement pump, refer to the Service Manual module Specifications, "Vane Pump (Steering, Implement, Pilot, and Braking)" for the machine that is being serviced.

9. A 10% decrease in the volume of oil flow is acceptable. If the flow rate is less than 90% of the required rate, the pump should be repaired or replaced.

10. Turn the engine start switch to the OFF position.

11. Release the pressure in the hydraulic system.

    Reference: For more information about releasing the hydraulic pressure, refer to the Service Manual module Testing and Adjusting, "System Pressure - Release" for the machine that is being serviced.

12. Remove the 4C-9910 Portable Hydraulic Tester and connect hose assembly (9) and (10) to the proper fittings on main control valve (8) .

13. Start the engine and check for any possible leaks. Check the level of the hydraulic oil in hydraulic tank (11) .

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Illustration 6	g00888771

14. When the test for the implement pump has been completed, place the steering frame lock in the UNLOCKED position.