Bench Test Procedure for Hydraulic Piston Pumps {5070} Caterpillar

Backhoe Loader

420F (S/N: LTG1-UP; JWJ1-UP; SKR1-UP)

420F2 (S/N: NMB1-UP; NSB1-UP; LBS1-UP)

420F2 IT (S/N: LYC1-UP; HWD1-UP)

420F2 ST (S/N: LYB1-UP; HWC1-UP)

430F (S/N: RDF1-UP; LNH1-UP; RGS1-UP; LDY1-UP)

430F2 IT (S/N: LYE1-UP; HWG1-UP)

430F2 ST (S/N: LYD1-UP; HWE1-UP)

432F (S/N: SEJ1-UP; PXR1-UP)

432F2 (S/N: LYJ1-UP; HWP1-UP)

434F (S/N: LDH1-UP; FLY1-UP)

440 (S/N: DC91-UP)

444F (S/N: LJJ1-UP; FBN1-UP; JXR1-UP)

444F2 (S/N: LYL1-UP; HWS1-UP)

450 (S/N: KJH1-UP)

450E (S/N: LYR1-UP)

450F (S/N: HJR1-UP)

Mini Hydraulic Excavator

301.5 (S/N: MNH1-UP)

301.6 (S/N: MY61-UP)

301.7CR (S/N: JH71-UP)

301.8 (S/N: H8X1-UP)

303.5E2 (S/N: AC51-UP; BG81-UP; CR91-UP; JWY1-UP)

303.5E2 CR (S/N: CR61-UP; DWD1-UP)

304E2 (S/N: CJ21-UP)

Off-Highway Truck/Tractor

772G (S/N: RMH1-UP)

Telehandler

TH306D (S/N: TD21-UP; TD31-UP)

TH336C (S/N: THM1-UP; MJR1-UP)

TH337C (S/N: DJB1-UP; SXJ1-UP)

TH3510D (S/N: TH21-UP; TH31-UP)

TH357D (S/N: TM31-UP; TD71-UP)

TH406 (S/N: TBX1-UP)

TH406C (S/N: RCH1-UP; GAT1-UP)

TH407 (S/N: TBY1-UP)

TH407C (S/N: MLH1-UP; JJT1-UP)

TH408D (S/N: TH41-UP; TH91-UP)

TH414 (S/N: TBZ1-UP)

TH414C (S/N: KEK1-UP; RWW1-UP)

TH417 (S/N: TBT1-UP)

TH417C (S/N: RRJ1-UP; RRW1-UP)

TH514 (S/N: TBW1-UP)

TH514C (S/N: MWC1-UP; KKW1-UP)

TH514D (S/N: MWG1-UP; MWY1-UP)

TL1055D (S/N: ML51-UP; MNT1-UP)

TL1255D (S/N: ML71-UP; MYW1-UP)

TL943D (S/N: MLD1-UP; MLJ1-UP)

Introduction

© 2018 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 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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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	g01178572
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	g01178573
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	g01178574
Connections for the test bench (26) "Flow meter 1" loop and "Flow meter 2" loop (27) Oil supply

Illustration 5	g01178575
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	g01178576
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) Control for the auxiliary oil supply (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

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

Illustration 7	g02885000
Port locations and schematic of pump (49) Solenoid valve (50) Adjustment screw for high-pressure cut (51) Adjustment screw for margin pressure (52) "X", "X1"Pressure port for load sensing (53) "L1", "L2"Case drain (54) "MB" Gauge port discharge pressure (55) "B" Discharge port (56) Electrical connector for solenoid (57) "S" Suction port

4C-3582 4C-3582 4C-3582 Load Sensing Valve

Illustration 8	g01178789
4C-3582 Load Sensing Valve

Illustration 9	g01178790
4C-3582 Load Sensing Valve

Illustration 10	g01178792
Schematic for 4C-3582 Load Sensing Valve (57) Outlet port (58) Adjustment for the discharge flow (59) Inlet port (60) High-pressure port (61) Adjustment for the discharge pressure (62) Low-pressure port (63) Pressure port for load sensing

Illustration 11	g01181465
4C-3582 Load Sensing Valve and 1U-5796 Pressure Differential Gauge (57) To the flow meter on the test bench (58) Adjustment knob for discharge flow (59) From the pump discharge port (60) To the high side of the differential gauge (61) Load control for pump discharge pressure (62) To the low side of the differential gauge (63) Pressure port for load sensing (64) Pressure differential gauge group (65) To the low side of the load sensing group (66) To the high side of the load sensing valve

Pump Setup

Note: A power supply will be required to operate the solenoid on this pump. The power supply must deliver 0 mA to 1260 mA with an infinite setting in that range.

Note: A sense pressure line from the pump should be connected to the load sensing pressure port (7) when you use the Caterpillar Hydraulic Test Center. A sense pressure line from the pump should be connected to the pressure port for load sensing (63) on the 4C-3582 Load Sensing Valve when using the Caterpillar Hydraulic Test Bench.

1. Connect a one-inch high-pressure "XT6 ES" hose from the pump discharge port (55) to inlet port (59) on the 4C-3582 Load Sensing Valve.

2. Connect a one-inch high-pressure "XT6 ES" hose from discharge port (55) on the 4C-3582 Load Sensing Valve to the flow meter inlet on the test bench.

3. Connect a one-inch high-pressure hose from the outlet of the flow meter on the test bench back to the tank.

4. Connect a 6D-7726 Hose Assembly to the pressure port for load sensing (63). Connect the other end of 6D-7726 Hose Assembly to the pressure port for load sensing (52) on the pump.

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

5. Connect the 1U-5796 Pressure Differential Gauge Group (64) to the high-pressure valve port (60) and low-pressure valve port (62) on the 4C-3582 Load Sensing Valve. The port marked "hi" (66) on the 1U-5796 Pressure Differential Gauge Group should be connected to the port marked "hi" (60) on the 4C-3582 Load Sensing Valve. The port marked "low" (65) on the 1U-5796 Pressure Differential Gauge Group should be connected to the port marked "low" (62) on the 4C-3582 Load Sensing Valve.

   Note: The ports marked "low" (62) and "sense line" (63) on the 4C-3582 Load Sensing Valve are reading the same pressure.

6. Connect a power supply to the electrical connector for solenoid valve (56) to operate the solenoid valve.

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

8. Fill the pump case with oil. Pour oil directly into a case drain port until the case is full.

9. Connect an in-line flow meter to the top Case drain port (53). Direct the oil from the in-line flow meter back to the tank.

10. If the pump is equipped with a gear pump, connect the discharge port of the gear pump to a flow meter with a high-pressure "XT-6 ES" hose. This will allow the gear pump flow to be tested. See Test Specifications to determine if the pump is equipped with a gear pump.

11. Do not rotate the pump in the wrong direction. The correct direction of rotation will be stated on the pump. The correct direction of rotation will also be in the test specifications. 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 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)

Note: For Steps 1, 2, 4, 5,6,7,8, and 9 of the Test Procedure be sure Adjustment knob for discharge flow (58) and Adjustment for the discharge pressure (61) are backed completely out on the 4C-3582 Load Sensing Valve.

1. Start rotating the pump to the RPM in Step 1 of the Test Specifications. Increase the signal current to Solenoid valve (49) to the value in Step 1 of the Test Specifications. Increase the discharge pressure to the value in Step 1 of the Test Specifications. Listen for abnormal noise. Verify flow from the pump. Verify that all the connections are not leaking. Check for leaks around shaft seals and control valves.

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

2. Slowly increase the pump RPM according to the value in Step 2 of the Test Specifications. Keep the signal current at the value in Step 2 of the Test Specifications. Keep the discharge pressure at the value in Step 2 of the Test Specifications. Verify that the discharge flow matches the value in Step 2 of the Test Specifications. The pump may not be mechanically feasible if the discharge flow values do not match.

3. Step 3 will check the margin pressure setting. Slowly increase the input RPM to the value in Step 3 of the Test Specifications. Keep the signal current at the value in Step 3 of the Test Specifications. The discharge flow is adjusted by using the 4C-3582 Load Sensing Valve. Bench circuitry will be used for flow limiting when you use a 1U-9400 Test Center.

   Decrease the discharge flow by turning Adjustment for discharge flow (58) according to the values in Step 3 of the Test Specifications. Adjust the discharge pressure according to the values in Step 3 of the Test Specifications. Adjust the Adjustment screw for margin pressure (51) to the value in Step 3 of the Test Specifications. The margin pressure will be displayed on the 1U-5796 Pressure Differential Gauge (64).

   Note: The margin pressure may change as discharge pressure changes. Adjust margin pressure in Step 3 only.

   Note: Before proceeding to Step 4, be sure to completely back out (counterclockwise) Adjustment knob for the discharge flow (58) and Adjustment knob for the discharge pressure (61) for the rest of this procedure.

   Note: Before proceeding to Step 4, do the following in order. Set the RPM to the value in Step 4 of the Test Specifications. Set the signal current to the value in Step 3 of the Test Specifications (maximum displacement). Set the discharge pressure to the value in Step 4 of the Test Specifications to ensure that the pump has sufficient control pressure. Leave the load control in this position during Steps 4,5,6, and 7.

4. Be sure to follow the above Note before proceeding. Steps 4,5,6, and 7 of the Test Procedure will verify the correct operation of the Solenoid valve (49). Step 4 of the Test Procedure will also verify that the pump will go to maximum displacement when the current is lost. Keep the RPM at the value in Step 4 of the Test Specifications. While watching the discharge flow meter, slowly decrease the input current from the value in Step 3 of the Test Specifications to the value in Step 4 of the Test Specifications. The pump should slowly destroke until the discharge flow reaches the value in Step 7 of the Test Specifications (minimum displacement) before returning to the value in Step 4 of the Test Specifications (maximum displacement). The pump should go to maximum displacement as the current drops below 400 mA (approximately). Keep the load control in the same position as performed in the Note above.

5. Increase the signal current to the value in Step 5 of the Test Specifications. Keep the load control in the same position. The pump should be at maximum displacement at this point. The flow should be close to the value in Step 5 of the Test Specifications.

6. Decrease the signal current to the value in Step 6 of the Test Specifications. The pump or the control for the solenoid valve (49) may not be mechanically feasible if the actual discharge flow is not close to the value in Step 6 of the Test Specifications.

7. Slowly decrease the signal current to the value in Step 7 of the Test Specifications. The pump should go to minimum displacement when the current is close to the mA value in Step 7 of the Test Specifications. The pump or the control for the solenoid valve (51) may not be mechanically feasible if the actual discharge flow is not close to the value in Step 7 of the Test Specifications.

   Note: Because this pump is designed to go to maximum displacement when the current drops below the value in Step 7 of the Test Specifications, the flow value observed in Step 7 of the Test Procedure should be noted just before the pump goes to maximum displacement. Once the pump goes to maximum displacement because the current drops below the mA value in Step 7 of the Test Specifications, the pump will remain at maximum displacement and the displacement cannot be adjusted with current until the current is increased to the mA value in Step 5 of the Test Specifications.

   Note: Some flow meters may not be able to read discharge flows at the minimum level in Step 7 of the Test Specifications. The flow meters may display "0".

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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 during adjustment of the high pressure relief valve if recommended hose maintenance practices are not followed. Escaping fluid under pressure can penetrate body tissue causing serious injury, and possible death. Adjustment of the high pressure cut or pressure override valve shall only be performed when the pump is operating at a zero discharge pressure condition. Continuation of the pump test procedure can be resumed when this high pressure adjustment is completed.

8. Increase the signal current 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. Measure the case drain using the in-line flow meter. The pump may not be mechanically feasible if the total loss is higher than the allowable value in Step 8 of the Test Specifications.

9. Step 9 will test the high-pressure cut. Increase the discharge pressure to the value in Step 9 of the Test Specifications. Turn Adjustment screw for the high-pressure cut (50) until the actual high-pressure cut value is equal to the value in Step 9 of the Test Specifications. Turn Adjustment screw for the high-pressure cut (50) clockwise to increase the high-pressure cut. Turn Adjustment screw for the high-pressure cut (50) counterclockwise to decrease the high-pressure cut. The 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 RPM and all pressures to zero. Remove the component from the test bench. Drain the oil from the pump. Plug all of the ports.

Test Specifications

Test Bench Tooling