Bench Test Procedure for Hydraulic Piston Pumps {0738, 5070} Caterpillar

Excavator

312F (S/N: FKE1-UP)

313F (S/N: GJD1-UP; HDK1-UP)

Material Handler

MH3037 (S/N: JPB1-UP; JLH1-UP; KPM1-UP)

MH3049 (S/N: HPB1-UP)

MH3059 (S/N: RBR1-UP)

Introduction

© 2015 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 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 questions or additional information concerning this guideline, submit a feedback form in the Service Information System web site. In order to address an urgent need, use the following to relay your request to Caterpillar Repair Process Engineering:

• Cat dealer Technical Communicator

• Dealer Solution Network

• Caterpillar Technical Representative

• Knowledge Network (online)

Canceled Part Numbers and Replaced Part Numbers

This document does not include 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) in order 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

Port Locations

Note: This piston pump is produced with multiple types of housing. Port locations will vary. Match the correct illustration with the pump that is being worked on.

Illustration 7	g03342248
(49) Electrical connector for power shift solenoid (50) Discharge port (51) Signal port for load sensing (52) Adjustment screw for margin pressure (53) Adjustment screw for constant power (54) Case drain port (55) Suction port (56) Adjustment screw for maximum angle (57) Adjustment screw for minimum angle

Illustration 8	g03343245
(50) Discharge port (51) Signal port for load sensing (52) Adjustment screw for margin pressure (53) Adjustment screw for constant power (54) Case drain port (55) Suction port

4C-3582 Load Sensing Valve

Illustration 9	g03342268
4C-3582 Load Sensing Valve

Illustration 10	g03342272
4C-3582 Load Sensing Valve

Illustration 11	g03342269
Schematic for 4C-3582 Load Sensing Valve (58) Outlet port (59) Adjustment for the discharge flow (60) Inlet port (61) High-pressure port (62) Adjustment for the discharge pressure (63) Low-pressure port (64) Pressure port for load sensing

Illustration 12	g03342270
4C-3582 Load Sensing Valve and 1U-5796 Pressure Differential Gauge (58) To the flow meter on the test bench (59) Adjustment knob for discharge flow (60) From the pump discharge port (61) To the high side of the differential gauge (67) (62) Load control for pump discharge pressure (63) To the low side of the differential gauge (66) (64) Pressure port for load sensing (65) Pressure differential gauge group (66) To the low side of the load sensing valve (63) (67) To the high side of the load sensing valve (61)

Note: Do not install the Load Sensing Valve until called for in Step 3 of the Test Procedure.

1. Connect a 1 inch high pressure (XT6) hose from pump discharge port (50) to inlet port (60) on the 4C-3582 Load Sensing Valve.

2. Connect a 1 inch high pressure (XT6) hose from outlet port (58) on the 4C-3582 Load Sensing Valve to the flow meter inlet on the test bench.

3. Connect a 6D-7726 Hose Assembly to the pressure port for load sensing (64). Connect the other end of 6D-7726 Hose Assembly to the pressure port for load sensing (51) on the pump.

   Note: Do not use 1U-5754 Hose Assembly or 1U-5755 Hose Assembly for sensing signal lines. The flow rate through these hoses will not compensate for the possible leakage through the control valve. Erratic readings will result.

4. Connect the 1U-5796 Pressure Differential Gauge Group (65) to the high-pressure port (61) and low-pressure port (63) on the 4C-3582 Load Sensing Valve. The port marked "hi" (67) on the 1U-5796 Pressure Differential Gauge Group should be hooked up to the port marked "hi" (61) on the 4C-3582 Load Sensing Valve. The port marked "low" (66) on the 1U-5796 Pressure Differential Gauge Group should be hooked up to the port marked "low" (63) on the 4C-3582 Load Sensing Valve.

Note: The ports marked "low" (63) and "sense line" (64) on the 4C-3582 Load Sensing Valve are reading the same pressure.

Pump Pre-Test Set Up

Note: A power supply is required to operate the solenoid. The power supply should be capable of delivering 0 mA to 1.2 A with an infinite setting in that range.

1. Connect a hose from the test bench oil supply (12) or (27) to suction port (55) on the pump.

2. 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.

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

4. Connect an in-line flow meter to the pump case drain port (54). Connect a hose assembly to the flow meter by using the proper fittings in order to direct the flow to the reservoir.

5. Connect a hose from pressure port (50) to the flow meter inlet on the test bench.

6. Connect power supply to the electrical connector for power shift solenoid (49).

7. 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 in the Test Specifications according to your specific part number.

Note: The hydraulic oil in the test bench should meet a contamination ISO rating of 16/13 or cleaner. 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 13	g01158251

This type of pump control purges the pressure for load sensing in order to limit system pressure. Therefore, no adjustment for maximum system pressure is done during this bench test. The limiter valve for the load sensing signal is located elsewhere in the hydraulic system. Refer to Testing and Adjusting, "Relief Valve (Signal Limiter) - Test and Adjust" for your specific machine.

1. Start rotating the pump according to the RPM in Step 1 of the Test Specifications. Listen for abnormal noise. Verify flow from the pump. Verify that all connections are tight. Check for leaks around shaft seals. Check for leaks around the control valve.

2. Slowly increase the input RPM to the value in Step 2 of the Test Specifications. If the actual flow is less than the value in Step 2 of the Test Specifications, adjust the adjustment screw for maximum angle (56) of the pump.

3. Reduce RPM and all pressures to zero. Use the following steps to set margin pressure.

   1. The 4C-3582 Load Sensing Valve should only be used during this step. The Load Sensing Valve limits the pump discharge flow. This loss of flow may cause erratic readings. Only use the Load Sensing Valve for Step 3 of the Test Specifications. Install the 4C-3582 Load Sensing Valve into the system. Refer to the heading "4C-3582 Load Sensing Valve" for instructions in order to install the Load Sensing Valve.

   2. Slowly increase the pump RPM to the value in Step 3 of the Test Specifications. To check the margin pressure setting, load the pump discharge by turning the adjustment knob for discharge pressure (62) clockwise until discharge pressure is equal to the value in Step 3 of the Test Specifications. Restrict flow by turning the adjustment knob for discharge flow (59) clockwise until discharge flow is equal to the value in Step 3 of the Test Specifications. Check the pressure reading on the 1U-5796 Pressure Differential Gauge. If the pressure is not within the specifications, adjust the adjustment screw for margin pressure (52) accordingly. Turn the load control for pump discharge pressure (62) and the adjustment knob for discharge flow (59) counterclockwise all the way after the margin pressure is set. Reduce RPM and all pressures to zero.

   3. Remove the 4C-3582 Load Sensing Valve from the system. Return hoses to the original positions.

4. Slowly increase the pump RPM to the value in Step 4 of the Test Specifications. Increase current to the Electrical connector for power shift solenoid (49) to the value in Step 4 of the Test Specifications. To check the destroke point of the pump, slowly increase discharge pressure to the value in Step 4 of the Test Specifications by turning the load control for discharge pressure (24) or (46) on the test bench, clockwise. Monitor the discharge flow while the pump pressure is increased. The pump should start to destroke at the value of discharge pressure in Step 4 of the Test Specifications. If the flow does not begin to decrease at this pressure, adjust the Adjustment screw for constant power (53). Turn clockwise in order to raise the destroke point. Turn counterclockwise in order to lower the destroke point.

   Note: For test benches with an input torque meter, the pump input torque will rise until the pump starts to destroke. The torque should remain constant at the value in Step 4 of the Test Specifications for the remaining two steps. The pump discharge pressure will increase while the discharge flow will decrease in order to keep the same input torque.

5. Increase the pump discharge pressure to the values in Step 5 of the Test Specifications. Compare the discharge flow to the value in Step 5 of the Test Specifications. This step further verifies the operation of the power compensator.

6. Increase the pump discharge pressure to the values in Step 6 of the Test Specifications. Compare the actual case drain flow with the value in Step 6 of the Test Specifications. If the pump case drain is not within specifications the pump may not be mechanically feasible. Internally inspect the pump.

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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. Remove the component from the test bench. Drain the oil from the pump. Plug all ports.

Test Specifications

Test Bench Tooling