Bench Test Procedure for Hydraulic Piston Pumps {4268, 4306, 5070} Caterpillar

Hydraulic Shovel

6020B (S/N: D4R1-UP; DNR1-UP)

Off-Highway Truck/Tractor

793F (S/N: SSP1-UP)

797 (S/N: 5YW251-253,258-UP)

797B (S/N: JSM1-UP)

797F (S/N: LAJ1-UP; WSP1-UP)

Wheel Loader

994H (S/N: DWC1-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 bay 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 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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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.

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

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	g02510476
Connections for the Test Center (1) Flow control for discharge (2) "F3" flow meter inlet (3) "F3" flow meter outlet (4) Return to tank (5) Connections for case drain (6) "F4" flow meter inlet (7) "F4" flow meter outlet (8) Return to tank (9) Oil supply

Illustration 3	g02510536
Control and Gauges for the Test Center (10) "F3" discharge pressure gauge (11) "F3" discharge flow (12) "F4" discharge pressure gauge (13) "F4" discharge flow (14) "F3" Load control for discharge pressure (15) "F4" Load control for discharge pressure

Connections for the Caterpillar Hydraulic Test Bench

Illustration 4	g02510556
Connections for the Test Bench (16) "Flow meter 1" loop and "Flow meter 2" loop (17) Oil Supply

Illustration 5	g02510461
Connections for the Test Bench (18) "Flow meter 2" loop (19) "Flow meter 1" loop (20) "Flow meter 2" outlet (21) "Flow meter 2" inlet (22) "Flow meter 1" outlet (23) "Flow meter 1" inlet

Illustration 6	g02510597
Control and Gauges for the Test Bench (24) "Flow meter 1" discharge pressure (25) "Flow meter 1" discharge flow (26) "Flow meter 1" load control (27) Speed and direction control (28) "Flow meter 2" discharge pressure (29) "Flow meter 2" discharge flow (30) "Flow meter 2" load control

Port Locations

Illustration 7	g02505996
Typical port locations and adjustments for type 1 pump. (31) Front electronic proportional control solenoid valve (32) Adjustment screw for solenoid (33) Adjustment screw for high-pressure cut (34) Suction port (35) Rear electronic proportional control solenoid valve (36) Adjustment screw for minimum angle (37) Case drain ports (38) Solenoid electrical connectors (39) Adjustment screw for maximum angle (40) Discharge ports (41) Gauge port for front pump discharge pressure (42) Gauge port for rear pump discharge pressure (43) Gauge port for rear pump actuator pressure (44) Suction pressure after charge pump (45) Gauge port for front pump actuator pressure

Illustration 8	g02507437
Schematic for type 1 pump (negative flow control shown). (34) Suction port (37) Case drain ports (40) Discharge ports (41) Gauge port for front pump discharge pressure (42) Gauge port for rear pump discharge pressure (43) Gauge port for rear pump actuator pressure (44) Suction pressure after charge pump (45) Gauge port for front pump actuator pressure

Illustration 9	g02502779
Typical port locations and adjustments for type 2 pump. (31) Front electronic proportional control solenoid valve (32) Adjustment screw for solenoid (33) Adjustment screw for high-pressure cut (34) Suction port (35) Rear electronic proportional control solenoid valve (36) Adjustment screw for minimum angle (37) Case drain ports (38) Solenoid electrical connectors (39) Adjustment screw for maximum angle (40) Discharge ports (41) Gauge port for front pump discharge pressure (42) Gauge port for rear pump discharge pressure (43) Gauge port for rear pump actuator pressure (45) Gauge port for front pump actuator pressure

Illustration 10	g02507458
Schematic for type 2 pump (positive flow control shown). (34) Suction port (37) Case drain ports (40) Discharge ports (41) Gauge port for front pump discharge pressure (42) Gauge port for rear pump discharge pressure (43) Gauge port for rear pump actuator pressure (45) Gauge port for front pump actuator pressure

9U-7500 9U-75009U-75009U-75009U-75009U-75009U-7500 9U-7500 9U-7500 Transmission Analyzer Tool Group Operating Instructions

Note: Refer to the Test Specifications in order to verify the type of flow control the pump has.

Note: Two power supplies will be required to perform this pump test for the negative flow control pumps. One power supply will be used to destroke the pump that is not being tested. The other power supply will be used to supply current to the test pump. For the type 1 pumps with negative flow control the power supplies must be able to deliver 0 mA to 600 mA. A 9U-7500 Transmission Analyzer Tool Group can be used for one of the power supplies when testing the type 1 pumps with negative flow control. For the type 2 pumps with negative flow control the power supplies must be able to deliver 0 mA to 1500 mA. The 9U-7500 Transmission Analyzer Tool Group is currently not capable of delivering 1500 mA. The type 1 pumps and type 2 pumps with positive flow control only require one power supply because the pump not being tested is de-stroked with no current applied. For the type 1 pumps with positive flow control the power supply must be able to deliver 0 mA to 600 mA. For the type 2 pumps with positive flow control the power supply must be able to deliver 0 mA to 1500 mA.

1. Turn on the 9U-7500 Transmission Analyzer Tool Gp. The Transmission Analyzer has two current input switches. One current switch is for AC. The other switch is for DC . Use one of the two power switches on the front panel for this procedure.

2. Three screens will appear in succession. The first two screens will appear momentarily. The third screen will be the"main menu" screen.

3. Use the arrow keys on the keyboard to move the cursor. Move the cursor to "PUMPS" and press "ENTER".

4. To test the type 1 pump, which is 24 V, move the cursor to "24V-STEPPED" and press "ENTER".

5. The next screen will read "SELECT A TEST KEY" at the bottom. Press the "XMSN TEST" key in order to test this pump.

6. The next screen will be "CONNECT TRANSMISSION TEST CABLE". Connect the transmission test cable and press "ENTER". A 1U-9480 Cable Adapter will be used to hook up the test cable to the pump solenoid.

7. The next screen will indicate the gear position of the transmission. This screen will read "TRANSMISSION TEST "NEUTRAL" ENTER GEAR".

   Note: Do not apply current to the pump solenoids at this time. Instructions will appear later in the procedure concerning current requirements.

8. Current is sent to the solenoid when a combination of "1F", "2F", or "3F" and "ENTER" are pressed. See Table 3 for current values.
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   Table 3

   Supply Current from 9U-7500 Transmission Analyzer Tool Group
   Key	Current
   N	0 mA
   1F	200 mA
   2F	400 mA
   3F	600 mA

9. To send zero current to the pump solenoid, press "N" and then press "ENTER".

Pump Pre-Test Set Up

Note: Refer to the Test Specifications in order to verify the type of that is being tested.

Note: Refer to the Test Specifications in order to verify the type of flow control the pump has.

Note: Two power supplies will be required to operate the solenoids with negative flow control. One power supply will be used to destroke the pump that is not being tested. The other power supply will be used to supply current to the test pump. The power supplies should be able to deliver 0 mA to 600 mA for the type 1 pump with negative flow control. The power supplies should be able to deliver 0 mA to 1500 mA for testing the type 2 pump with negative flow control. The testing points will be 0 mA, 200 mA, 400 mA, and 600 mA for the type 1 pump. The testing points will be 0 mA, 500 mA, 1000 mA, and 1500 mA for the type 2 pump. The type 1 pumps and type 2 pumps with positive flow control only require one power supply because the pump not being tested is de-stroked with no current applied. For the type 1 pumps with positive flow control the power supply must be able to deliver 0 mA to 600 mA. For the type 2 pumps with positive flow control the power supply must be able to deliver 0 mA to 1500 mA.

1. 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.

2. Fill both pump cases with oil before rotating. Pour oil directly into a case drain port until the case is full.

3. 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 pump for proper rotation.

Test Procedure

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

The hydraulic oil in the test bench should meet an ISO rating of 16/13. 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 11	g00946725
Negative Flow Control

Illustration 12	g02511288

Note: Always remove all pump discharge pressure before decreasing the solenoid current to zero. If this is not done, the discharge pressure will increase rapidly.

Note: Refer to the Test Specifications in order to verify the type of that is being tested.

Note: Refer to the Test Specifications in order to verify the type of flow control the pump has.

1. Start rotating the pump according to the input speed in Step 1 of the Test Specifications.

   For type 1 pumps with negative flow control apply 600 mA of current in order to de-stroke the pump that will not be tested. Slowly increase discharge pressure until flow from the pump not being tested is at zero or close to zero. Listen for abnormal noise. Verify the flow from the pump that is being tested. Verify that all connections are tight. Check for leaks around shaft seals. Check for leaks around the control valve.

   For type 2 pumps with negative flow control apply 1500 mA of current in order to de-stroke the pump that will not be tested. Slowly increase discharge pressure until flow from the pump not being tested is at zero or close to zero. Listen for abnormal noise. Verify the flow from the pump that is being tested. Verify that all connections are tight. Check for leaks around shaft seals. Check for leaks around the control valve.

   For positive flow control pumps, there is no need to apply current to the pump not being tested because the pump is de-stroked with no current applied. Slowly increase discharge pressure until flow from the pump not being tested is at zero. Listen for abnormal noise. Verify the flow from the pump that is being tested. Verify that all connections are tight. Check for leaks around shaft seals. Check for leaks around the control valve.

   Run the pump for at least 5 minutes in order to raise the temperature of the oil and purge the system of air.

2. Slowly increase the input RPM to the value in Step 2 of the Test Specifications. If the discharge flow of the pump does not match Step 2 of the Test Specifications, adjustment will be required.

   The pumps with negative flow should be at maximum displacement. If the value is not within specifications, adjustment of the adjustment screw for maximum angle (39) will be required. Turn the adjustment screw for maximum angle (39) clockwise in order to decrease flow. Turn the adjustment screw for maximum angle (39) counterclockwise in order to increase flow.

   The pumps with positive flow should be at minimum displacement. If the value is not within specifications, adjustment of the adjustment screw for minimum angle (36) will be required. Turn the adjustment screw for minimum angle (36) clockwise in order to increase flow. Turn the adjustment screw for minimum angle (36) counterclockwise in order to decrease flow.

3. Slowly increase the pump discharge pressure to the value in Step 3 of the Test Specifications. Note the discharge flow.

4. Apply the current value in Step 4 of the Test Specifications. Apply current to the pump that is being tested. If necessary, adjust the discharge pressure to the value in Step 4 of the Test Specifications. The discharge flow should equal the value in Step 4 of the Test Specifications. If the discharge flow is too low, turn the adjustment screw for solenoid (32) clockwise. If the discharge flow is too high, turn the adjustment screw for solenoid (32) counterclockwise. No further adjustment of the adjustment screw for solenoid (32) is necessary.

5. Increase the current to the value in Step 5 of the Test Specifications.

   Discharge flow should go down to the value in Step 5 of the Test Specifications for pumps with negative flow control.

   Discharge flow should go up to the value in Step 5 of the Test Specifications for pumps with positive flow control.

6. Increase the current to the value in Step 6 of the Test Specifications.

   Discharge flow should go down to the value in Step 6 of the Test Specifications for pumps with negative flow control.

   Discharge flow should go up to the value in Step 6 of the Test Specifications for pumps with positive flow control.

   If the discharge flow does not equal the value in Step 6 of the Test Specifications, turn the adjustment screw for minimum swashplate angle (36) for pumps with negative flow control that is being tested. Turn adjustment screw for minimum swashplate angle (36) clockwise in order to increase the flow for pumps with negative flow control. Turn adjustment screw for the minimum swashplate angle (36) counterclockwise in order to decrease flow for pumps with negative flow control.

   If the discharge flow does not equal the value in Step 6 of the Test Specifications, turn the adjustment screw for maximum swashplate angle (39) for pumps with positive flow control that is being tested. Turn adjustment screw for maximum swashplate angle (39) clockwise in order to decrease the flow for pumps with positive flow control. Turn adjustment screw for the maximum swashplate angle (39) counterclockwise in order to increase flow for pumps with positive flow control.

7. Remove all discharge pressure from the pump that is being tested.

   Then, for pumps with negative flow control, lower the current to zero . Do not lower the current first. The pump discharge pressure will immediately go to the high-pressure cut value.

   For pumps with positive flow control apply current to the value in Step 7 of the Test Specifications.

   Increase the pump discharge pressure to the value in Step 7 of the test specifications. Compare the actual values for the case drain with the values in Step 7 of the test specifications. This value is an indication of the efficiency. If the case drain is more than the value given in Step 7 of the test specifications, the pump may not be mechanically feasible. Internally inspect the pump.

8. Slowly adjust the input RPM to the value in Step 8 of the Test Specifications. Increase the pump discharge pressure to the value in Step 8 of the Test Specifications. Apply current to the value in Step 8 of the Test Specifications. Turn the adjustment screw for the high-pressure cut until the actual high-pressure cut value is equal to the value in Step 8 of the Test Specifications. The discharge flow should be zero when the high-pressure cut is reached.

Complete Steps 1 through 8 of the Test Procedure on the other half of the tandem pump. Match the pump that is being tested to the correct test specifications. Some of the specifications are different between the front and rear pumps.

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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 RPM and all pressures to zero. Reduce the voltage and current to zero. Remove the component from the test bench. Drain the oil from the pump. Plug all of the ports.

Test Specifications

Tooling