Bench Test Procedure for Hydraulic Piston Pumps {0784, 5070} Caterpillar

Vibratory Utility Compactor

CB1.7 (S/N: SA71-UP; HRB1-UP)

CB1.8 (S/N: MP91-UP; ERX1-UP)

Introduction

© 2018 Caterpillar All Rights Reserved. This guideline is for the use of Caterpillar Dealers only. Unauthorized use of this document or the proprietary processes therein without permission may be violation of intellectual property law. Information contained in this document is considered Caterpillar: Confidential Yellow.

This Special Instruction includes test procedures for piston pumps. This Special Instruction also provides specifications. The technician should have a good understanding of hydraulic piston pumps. The technician should be educated in the operation of the hydraulic test bench. The test benches in this document are available through the Caterpillar Service Tool Division. Gather all necessary tooling before you need to hook up the pump. Some of the required tooling appears in a table at the end of this document. There are many possible variations of tooling that could be used. Not every possible variation can be listed.

For questions or additional information concerning this guideline, submit a feedback form in the Service Information System website. To address an urgent need, please use the following to relay your request to Caterpillar Repair Process Engineering:

• Cat Dealer Technical Communicator

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Canceled Part Numbers and Replaced Part Numbers

This document may not include all Canceled part numbers and replaced part numbers. Use NPR on SIS for information about Canceled part numbers and replaced part numbers. NPR will provide the current part numbers for replaced parts.

Safety

Illustration 1	g02139237

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Personal injury or death can result from improperly checking for a leak. Always use a board or cardboard when checking for a leak. Escaping air or fluid under pressure, even a pin-hole size leak, can penetrate body tissue causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.

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Hot oil and hot components can cause personal injury. Do not allow hot oil or hot components to contact skin.

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Pump test pressures in this guideline may exceed the normal operating range of the hydraulic test hoses utilized when connecting the tested pump to the test bench. However, the order of magnitude of these pressures is significantly below the burst strength of the Caterpillar "XT6" product. High pressure oil can escape through improperly assembled hoses and fittings. High pressure oil can also escape through poorly maintained hoses and fittings. High pressure oil may also leak through hose that has become damaged over the life of the hose due to the pressure levels that occur during test bench operation. Personal injury or death can result from improper hose & fitting inspection or improper hose replacement procedures. Escaping fluid under pressure can penetrate body tissue causing serious injury, and possible death. Thoroughly inspect all testing hoses, fittings, and quick disconnects prior to any testing operation. Check the assembly date tag or hose assembly log date for a hose life indicator. Replace all Test Bench hoses at a minimum of every 2 years or earlier if the hose or fittings appear to be damaged.

Summary

This procedure is specific to the type of pump and the type of control. Refer to the test specifications and the tooling at the end of this document.

Note: A paper copy of this document may not be the latest version. Go to the Service Information System (SIS) to view the latest version.

References

Connections for the Caterpillar Hydraulic Test Center

Illustration 2	g01140178
Connections for the test center (1) Flow control for discharge (2) F3 Flow meter inlet (3) F4 Flow meter inlet (4) Oil supply from the auxiliary pump (5) F3 inlet for the flow meter with flow limiter (6) F3 outlet for the flow meter with pressure control (7) Load sensing pressure (8) Signal pressure (9) F4 outlet for the flow meter (10) Return to tank (11) Connections for case drain (12) Oil supply

Illustration 3	g01140179
Control and gauges for the test center (13) Meter for speed and torque (14) Gauge for signal pressure (15) Control for signal pressure (16) Pressure gauge for auxiliary pump (17) Auxiliary pump flow (18) F3 discharge pressure gauge (19) F3 discharge flow (20) F4 discharge pressure gauge (21) F4 discharge flow (22) Auxiliary pump flow control (23) F3 margin pressure (24) F3 Load control for discharge pressure (25) F4 Load control for discharge pressure

Connections for the Caterpillar Hydraulic Test Bench

Illustration 4	g01140180
Connections for the test bench (26) Flow meter 1 loop and flow meter 2 loop (27) Oil supply

Illustration 5	g01140183
Connections for the Test Bench (28) Flow meter 2 loop (29) Flow meter 1 loop (30) Flow meter 2 outlet (31) Signal pressure line (32) Flow meter 2 inlet (33a) Flow meter 1 outlet (33b) Auxiliary oil supply outlet (34) Auxiliary oil supply inlet (35) "Flow meter 1" inlet

Illustration 6	g01140185
Control and gauges for the test bench (36) Auxiliary oil supply pressure (37) Signal pressure (38) Control for signal pressure (39) Flow meter 1 discharge pressure (40) Control for auxiliary oil supply pressure (41) Flow meter 2 discharge pressure (42) Auxiliary oil supply control (43) Flow meter 2 discharge flow (44) Discharge flow for auxiliary pump (45) Flow meter 1 discharge flow (46) Flow meter 1 load control (47) Speed and direction control (48) Flow meter 2 load control

Pump Illustrations

Illustration 7	g06298661
Port locations and adjustments: (49) Case drain port (50) Discharge port (51) Discharge port (52) Charge pump suction port (53) Cross-over relief valve (54) Electrical connector for brake release solenoid (55) Adjustment screw for charge relief valve (56) Charge pump discharge port (57) Cross-over relief valve (58) Mechanical displacement lever (59) Gauge port for brake release pressure (60) Charge oil inlet port

Illustration 8	g06298680
Hydraulic schematic: (49) Case drain port (50) Discharge port (51) Discharge port (52) Charge pump suction port (53) Cross-over relief valve (54) Electrical connector for brake release solenoid (55) Adjustment screw for charge relief valve (56) Charge pump discharge port (57) Cross-over relief valve (58) Mechanical displacement lever (59) Gauge port for brake release pressure (60) Charge oil inlet port

9U-5902 Rectifier Block

Illustration 9	g01121880
9U-5902 Rectifier Block Connections (61) High-pressure port "from pump discharge" (62) Outlet "to flow meter loop" (63) High-pressure port "from pump discharge" (64) Low-pressure return "from heat exchanger"

Illustration 10	g01121883
9U-5902 Rectifier Block Schematic (61) High-pressure port "from pump discharge" (62) Outlet "to flow meter loop" (63) High-pressure port "from pump discharge" (64) Low-pressure return "from heat exchanger"

9U-5893 Heat Exchanger

Illustration 11	g01121877
9U-5893 Heat Exchanger Connections (65) Inlet "from flow meter loop" (66) Outlet "to rectifier block" (67) Water inlet (68) Water outlet

Pump Set Up

1. Mount the pump with case drain port (49) facing upward.

2. Connect pump discharge port (50) to the 9U-5902 Rectifier Block high-pressure port (61). Connect pump discharge port (51) to the 9U-5902 Rectifier Block high-pressure port (63).

3. Connect the 9U-5902 Rectifier Block outlet (62) to the flowmeter inlet on the test bench.

4. Connect the flowmeter outlet to the 9U-5893 Heat Exchanger inlet (65).

5. Connect the 9U-5893 Heat Exchanger outlet (66) to the low-pressure return (64) on the 9U-5902 Rectifier Block.

6. Connect a hose from the charge pump suction port (52) to the auxiliary oil supply on the test bench.

7. Connect a hose from the charge pump discharge port (56) to the charge oil inlet port (60) on the pump.

8. Fill the pump case with oil through case drain port (49). Connect an in-line flowmeter to case drain port (49) and direct the case drain flow back to the test bench.

9. Connect an electrical power supply to the electrical connector for brake release solenoid (54). The electrical power supply should be able to deliver 0 mA to 1.5 mA with an infinite setting in that range.

10. Do not rotate the pump in the wrong direction. The correct direction of rotation will be stated on the pump. The direction of rotation is viewed from the input shaft end. Visually check the rotation of the test bench to ensure proper direction.

Test Procedure

Note: The steps in the procedure correlate with the steps under the test specifications according to your specific part number.

The contamination level of the hydraulic oil in the test bench should be ISO 16/13 or better. The oil in the test bench should be one of the following.

• SAE 10W at 50 °C (122 °F) or

• Mobil DTE-11 at 46 °C (115 °F)

1. This step will verify correct pump set up an allow the oil to warm

   Start rotating the pump according to the input speed in Step 1 of the Test Specifications. Listen for abnormal noise and vibrations. Verify that all connections are secure and tight. Check for leaks around control valves. Run the pump for at least 5 minutes to raise the temperature of the oil and purge the system of air.

2. This step will verify the charge relief valve setting.

   Slowly increase the input speed to the value given in Step 2 of the test specifications. Verify correct charge pressure. If the charge pressure is not correct according to the Test Specification, the charge relief valve must be adjusted. Adjust the charge relief valve by turning the adjustment screw for charge relief valve (55) clockwise or counterclockwise accordingly.

3. This step will verify the maximum displacement setting of one side of the pump.

   Apply electrical current to the electrical connector for brake release solenoid (54) according to Step 3 of the Test Specifications. Turn the mechanical displacement lever (58) completely clockwise. Verify correct discharge flow according to Step 3 of the Test Specifications. If the discharge flow is not within specification, the pump may not be mechanically feasible and may need to be internally inspected.

4. This step will verify pump efficiency.

   Slowly increase pump discharge pressure to the value in Step 4 of the Test Specifications. Measure pump leakage. Calculate the total loss. The pump may not be mechanically feasible if the total loss is higher than the allowable value in step 4 of the Test Specifications.

   Subtract the discharge flow that was recorded in Step 4 of the Test Procedure from the discharge flow that was recorded in Step 3 of the Test Procedure to find total loss.

   Example: "Step 3 flow" 162 L (42.8 US gal) - Step 4 flow" 158 L (41.7 US gal) = total loss 4 L (1.1 US gal). The max. allowable loss" is 7.2 L (1.9 US gal).

   The pump in the example is acceptable because the actual loss is less than the maximum allowable loss.

5. This step will verify the crossover relief setting of one side of the pump.

   Slowly increase pump discharge pressure to the value in Step 5 of the Test Specifications. Discharge flow should drop to zero. If discharge flow does not drop to zero, the crossover relief valve may not be functioning properly.

6. This step will verify maximum displacement of the other side of the pump.

   Reduce discharge pressure to the value in Step 6 of the Test Specifications. Turn the mechanical displacement lever (58) completely counterclockwise. Verify correct discharge flow according to Step 6 of the Test Specifications. If the discharge flow is not within specification, the pump may not be mechanically feasible and may need to be internally inspected.

7. This step will verify the crossover relief setting of the other side of the pump.

   Slowly increase pump discharge pressure to the value in Step 7 of the Test Specifications. Discharge flow should drop to zero. If discharge flow does not drop to zero, the crossover relief valve may not be functioning properly.

Once testing is complete reduce all pressures, electrical currents, speeds, and flow to zero. Allow the component to cool. Drain all oil from the component. Cap or plug all ports.

Test Specifications

Tooling