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

Mini Hydraulic Excavator

303.5C (S/N: CRL1-UP; DMY1-UP)

303.5D (S/N: SEG1-UP; RHP1-UP)

303.5E (S/N: JX21-UP; RSE1-UP; SFH1-UP; RKY1-UP)

303C (S/N: AZS1-UP; BXT1-UP)

303E (S/N: CR71-UP; SGE1-UP; SMG1-UP; HHM1-UP)

303E CR (S/N: CK31-UP; FR31-UP)

304C (S/N: STB1-UP; FPK1-UP; ENW1-UP)

304D (S/N: TYK1-UP)

304E (S/N: SSC1-UP; TTN1-UP; TSR1-UP)

305.5E (S/N: YGB1-UP; FSC1-UP; FKY1-UP)

305D (S/N: WCJ1-UP; XER1-UP)

305E (S/N: XFA1-UP; XSC1-UP; WDL1-UP)

308E (S/N: HEL1-UP; HAM1-UP)

Introduction

© 2016 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

Pump Illustrations

Illustration 7	g03693984
Port locations (49a) Case drain port (49b) Case drain port (50) Pilot pump discharge port (51) Load sense pressure port (52) Adjustment screw for margin pressure (53) Suction port (54) Control pressure port (55) Gauge port for stroking pressure (56) Discharge port (57) Adjustment screw for flow control

Illustration 8	g03865541
Hydraulic schematic (49a) Case drain port (49b) Case drain port (50) Pilot pump discharge port (51) Load sense pressure port (52) Adjustment screw for margin pressure (53) Suction port (54) Control pressure port (55) Gauge port for stroking pressure (56) Discharge port

4C-3582 4C-35824C-3582 4C-35824C-3582 4C-35824C-3582 4C-35824C-3582 4C-35824C-35824C-3582 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 (62) Load control for pump discharge pressure (63) To the low side of the differential gauge (64) Pressure port for load sensing (65) Pressure differential gauge group (66) To the low side of the load sensing group (67) To the high side of the load sensing valve

Pump Setup

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 (64) on the 4C-3582 Load Sensing Valve when using the Caterpillar Hydraulic Test Bench.

1. Connect a suction hose from the oil supply to the pump suction port (53)

2. Connect a 1 inch high pressure "XT6" hose from the pump discharge port (56) to a tee. Connect the tee to the inlet port (60) on the 4C-3582 Load Sensing Valve. Install a pressure tap in the third outlet of the tee that will be used later in Step 3 of the "Test Procedure".

3. 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.

4. Connect a 1 inch high-pressure "XT6" hose from the outlet of the flow meter on the test bench back to the tank.

5. Connect a 1 inch high pressure "XT6" hose from the pilot pump discharge port (50) to a flow meter inlet on the test bench.

6. Connect a 1 inch high pressure "XT6" hose from the outlet of the flow meter on the test bench back to the tank.

7. 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 load sensing pressure port (51) 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.

8. Connect the 1U-5796 Pressure Differential Gauge Group (65) to the high-pressure valve port (61) and low-pressure valve 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.

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

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

11. Connect an in-line flow meter to the case drain port (49a) or (49b). Direct the oil from the in-line flow meter back to the tank.

12. 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 1,2,3,5, and 5 be sure Adjustment knob for discharge flow (59) and Adjustment for the discharge pressure (62) are backed completelyout on the 4C-3582 Load Sensing Valve.

1. Start rotating the pump according to the input speed 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 speed to the value in Step 2 of the "Test Specifications". Increase pilot pump discharge pressure to value given in Step 2 of the "Test Specifications". If the discharge flow is less than the value in Step 2, the pump may not be mechanically feasible. The pump should be internally inspected.
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   NOTICE
   Reduce all pressures and input speeds to zero when making hose connections or disconnections. Resume input speeds and pressures after connection or disconnection has been made.

3. For this step, connect a high pressure hose from the tee in the discharge pressure line to the control pressure port (54).

   Slowly increase discharge pressure to the value in Step 3 of the "Test Specifications". Verify that discharge flow decreases to minimum. If the discharge flow is not equal to the value in Step 3 the pump may not be mechanically feasible. The pump should be internally inspected.

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   NOTICE
   Reduce all pressures and input speeds to zero when making hose connections or disconnections. Resume input speeds and pressures after connection or disconnection has been made.

4. For this step, disconnect control pressure port (54) from the pump discharge pressure line. Vent control pressure port (54) to atmosphere. The discharge flow is adjusted using the 4C-3582 Load Sensing Valve. Bench circuitry will be used for flow limiting when using a 1U-9400 Test Center. Decrease the discharge flow according to the values in Step 4 of the "Test Specifications". Adjust the screw for margin pressure (52) to the value in Step 4 of the "Test Specifications". The margin pressure will be displayed on the 1U-5796 Pressure Differential Gauge (64).

5. For this step be sure that the adjustment knob for discharge flow (59) is backed completelyout. Increase discharge pressure to the value in Step 5 of the "Test Specifications". Compare the actual flow from the case drain port (49a) or (49b) to the value in Step 5 of the "Test Specifications". This value is an indication of pump efficiency. If the case drain is more than the value given in Step 5, the pump may not be mechanically feasible. The pump should be internally inspected.
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   NOTICE
   Reduce all pressures and input speeds to zero when making hose connections or disconnections. Resume input speeds and pressures after connection or disconnection has been made.

6. For this step, connect a high pressure hose from the tee in the discharge pressure line to the load sense pressure port (51).

   Increase discharge pressure to the value in Step 6 of the "Test Specifications". Verify that the discharge flow is equal to the value given in Step 6 of the "Test Specifications". If the discharge flow is not within specifications, adjust the screw for flow control (57) until the flow is within specifications.

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

Test Specifications

Bench Test Tooling