Bench Test Procedure for Hydraulic Piston Pumps {5070} Caterpillar

Asphalt Paver

AP555F (S/N: AP51-UP; M451-UP; RBM1-UP)

AP600F (S/N: AP61-UP; LR61-UP)

AP655F (S/N: 4801-UP; 4521-UP; 4531-UP; P651-UP; 6551-UP; MH61-UP; ML61-UP; 4791-UP)

AP655F L (S/N: AC61-UP)

Introduction

© 2017 Caterpillar All Rights Reserved. This guideline is for the use of Cat 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 Dealer Service Tools. 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 technical questions when using this document, work with your Dealer Technical Communicator (TC).

To report suspected errors, inaccuracies, or suggestions regarding the document, submit a form for feedback in the Service Information System (SIS Web) interface.

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. The test procedure should be used with the Test Specifications and the Bench Test Tooling sections 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	g01063311
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	g01063312
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	g01063314
Connections for the Test Bench (26) "Flow meter 1" loop and "Flow meter 2" loop (27) Oil Supply

Illustration 5	g01093468
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	g01063316
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	g03745278
Port locations (49) Case drain port (50) Suction port (51) Adjustment screw for pressure cutoff (52) Electrical connector for on/off solenoid (53) Discharge port (54) Case drain port

Illustration 8	g03745279
Hydraulic schematic (49) Case drain port (50) Suction port (51) Adjustment screw for pressure cutoff (52) Electrical connector for on/off solenoid (53) Discharge port (54) Case drain port

Pump Setup

1. Connect a one-inch high-pressure "XT-6" rated hose from the pump discharge port (53) to the flow meter inlet on the test bench.

2. Connect a one-inch high-pressure "XT-6" rated hose from the flow meter outlet on the test bench back to the tank.

3. Connect the oil supply suction hose from the test bench oil supply to the pump suction port (50).

4. Purge all air from the suction line before rotating the pump. Loosen the suction hose at the pump until oil leaks from the connection. Tighten the suction hose connection.

5. Fill the pump case with oil before rotating. Pour oil directly into the highest case drain port (49) or (54) until the case is full.

6. Connect an in-line flow meter to the highest case drain port (49) or (54). Direct the oil from the in-line flow meter back to the tank.

7. Connect electrical connector for on/off solenoid (52) to an electronic power supply.

8. 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 for proper rotation of the test bench.

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)

Illustration 9	g03745464
Pump Characteristics (F) Discharge Flow (P) Discharge Pressure

1. Start rotating the pump according to the RPM in Step 1 of the Test Specifications. Listen for abnormal noise and verify flow from the pump. Be sure that all connections are secure and not leaking. Check for leaky shaft seals and control valve connections.

2. Slowly increase the input RPM to the value in Step 2 of the Test Specifications. Increase pump discharge pressure to the value given in Step 2 of the Test Specifications. The pump may not be feasible if the actual flow is less than the value in Step 2 of the Test Specifications. The pump should be disassembled and inspected.

3. Reduce input speed according to Step 3 of the Test Specifications. Increase current to the electrical connector for on/off solenoid (52) according to Step 3 of the Test Specifications. The discharge flow should decrease to minimum according to Step 3 of the Test Specifications. The discharge pressure should decrease to minimum according to Step 3 of the Test Specifications. If the discharge flow and discharge pressure do not decrease, the on/off solenoid (52) may not be functioning properly.

4. Reduce current to the electrical connector for on/off solenoid (52) according to Step 4 of the Test Specifications. Increase input speed according to Step 4 of the Test Specifications. Increase the pump discharge pressure to the value in Step 4 of the Test Specifications. Compare the actual case drain value with the case drain value in Step 4 of the Test Specifications. This value is an indication of the pump efficiency. The pump may not be feasible if the case drain is more than the value in Step 4 of the Test Specifications. The pump should be disassembled and inspected.

5. Increase the pump discharge pressure to the value in Step 5 of the Test Specifications. Turn the adjustment screw for the pressure cutoff (51) until the actual high-pressure cut value is equal to the value in Step 5 of the Test Specifications. Pump discharge flow should be zero when the high-pressure cut is reached.

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

Reduce the input speed and all pressures to zero. Remove the component from the test bench. Drain the oil from the pump. Cap and plug all ports.

Test Specifications

Bench Test Tooling