Bench Test Procedure for Hydraulic Piston Pumps{3203, 5070} Caterpillar

Agricultural Tractor:

65 (S/N: 7YC1-UP)

65B (S/N: 7YC1-UP)

65C (S/N: 2ZJ1-999,1000-1788)

65D (S/N: 2ZJ1000-1788)

70C (S/N: 2YL1-999,1000-1299)

75 (S/N: 4CJ1-435,436-UP)

75C (S/N: 4KK1-999,1000-2036)

85C (S/N: 9TK1-999,1000-1553)

Excavator:

5230 (S/N: 7LL1-UP)

5230B (S/N: 4HZ1-UP)

Forwarder:

554 (S/N: 1AM1-UP)

574 (S/N: 1FM1-UP)

Wheel Harvester:

550 (S/N: 7ZN1-UP)

550B (S/N: SAW1-UP)

560B (S/N: TRA1-UP)

570 (S/N: 4XR1-UP)

570B (S/N: CKG1-UP)

580 (S/N: 7CN1-UP)

580B (S/N: CLT1-UP)

Track-Type Loader:

953C (S/N: 2ZN1-1751,1752-3818,3819-UP; BBX1-UP)

Introduction

© 2014 Caterpillar All Rights Reserved. This guideline is for the use of Caterpillar 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 questions or additional information concerning this guideline, submit a feedback form in the Service Information System website. 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

• Cat Technical Representative

• Knowledge Network (online)

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) in order 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	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

Illustration 7	g01441319
Typical port locations and adjustment locations. (49) Case drain port (50) Suction port for the pilot pump (51) Signal pressure port (52) Crossover relief valve (53) Discharge port (54) Pressure port for load sensing (55) Slotted carrier (56) Locknut (57) Locknut (58) Adjustment screw for maximum angle

9U-5902 Rectifier Block

Illustration 8	g01441328

Illustration 9	g01441331
9U-5902 Rectifier Block Schematic (59) High-pressure port "from pump discharge" (60) Outlet "to flow meter loop" (61) High-pressure port "from pump discharge" (62) Low-pressure return "from heat exchanger"

9U-5893 Heat Exchanger

Illustration 10	g01441332
9U-5893 Heat Exchanger Connections (63) Inlet "from flow meter loop" (64) Outlet "to rectifier block" (65) Water inlet (66) Water outlet

Pump Pre-Test Set Up

1. Refer to Illustration 7. Install quick disconnect fittings in signal pressure port (51). Install quick disconnect fittings in signal pressure port (54) .

   Connect signal pressure from the test bench to the signal pressure port (51). Connect a quick disconnect fitting to the signal pressure port (54) in order to vent the pilot control valve to the atmosphere.

2. Connect pump discharge ports (53) to the 9U-5902 Rectifier Block high-pressure ports (59) and (61) .

3. Connect the 9U-5902 Rectifier Block outlet (60) to the flow meter inlet on the test bench.

4. Connect the outlet of the flow meter on the test bench to the 9U-5398 Heat Exchanger inlet (63) .

5. Connect the 9U-5398 Heat Exchanger outlet (64) to the low-pressure return (62) on the 9U-5902 Rectifier Block .

6. Connect the charge oil inlet port (50) to the auxiliary oil supply of the test bench. Set the charge pressure for the auxiliary pump to the value in Step 1 of the test specifications.

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

   Once the case is full of oil, connect a hose from the upper case drain port to the oil sump of the test bench.

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 the pump for proper rotation.

Test Procedure

Note: The steps in the procedure correlate with the steps in the tables for the test specification 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	g00996372

Illustration 12	g00996374

1. Supply the pump with enough charge oil from the auxiliary pump of the test bench in order to obtain the correct charge pressure. Increase the flow from the charge pump until the value in Step 1 of the test specifications is obtained.

   Note: Throughout the test procedure, verify that correct charge pressure is maintained in order to supply sufficient makeup oil.

   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.

   Apply signal pressure to the signal pressure port (51) in order to upstroke the pump. Run the pump for at least 10 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. Increase the signal pressure in Step 2 to signal pressure port (51). This is the point of upstroke for the pump. If the actual discharge flow is not correct, adjust the point of upstroke on the control for signal pressure.

   Note: Some flow meters may not be able to read discharge flows at this level. If the flow is not measurable on the flow meter, increase the signal pressure to a value higher than the value in Step 2 of the test specifications. Continue increasing the pressure until the flow can be measured by the flow meter. Verify the point of upstroke. The point of upstroke should be near the value in Step 2 of the test specifications.

   To adjust the point of upstroke, loosen the locknut (56a) on the slotted carrier (55a). Adjust the point of upstroke by slowly turning slotted carrier (55a). Turning a quarter turn clockwise will increase the point of upstroke by approximately 16 kPa (2.3 psi). Turning a quarter turn counterclockwise will decrease the point of upstroke by 16 kPa (2.3 psi).

3. Increase the signal pressure to the value in Step 3of the test specifications to signal pressure port (51) .

4. Increase the signal pressure to the value in Step 4of the test specifications to the signal pressure port (51). The pump should be fully upstroked at this time. Record actual pump flow. If the actual flow is not equal to the value in Step 4 of the test specifications, adjust the set screw for maximum displacement (58b) on the control for signal pressure.

   To adjust the maximum displacement, loosen the locknut (57b) on the set screw for maximum displacement (58b). Adjust the maximum displacement by slowly turning the set screw for maximum displacement (58b). Turning a quarter turn clockwise will increase the maximum displacement by approximately 2 L (0.5 US gal). Turning a quarter turn counterclockwise will decrease the point of upstroke by 2 L (0.5 US gal).

5. Use the following steps to determine pump efficiency.

   1. Change the signal and discharge pressures to the values in Step 5.a of the test specifications. The pump should be fully upstroked at this time. Record actual pump flow.

   2. Increase the pump discharge pressure to the value in Step 5.b of the test specifications. Measure pump leakage. Calculate the total loss. If the total loss is higher than the allowable value in Step 5.b of the test specifications, the pump may not be mechanically feasible.

      Subtract the "discharge flow" in Step 5.b from the "pump discharge flow" in Step 5.a. This is your total loss.

      Example: "Step 5a flow"162 L/min (43 US gpm) - "Step 5b flow"158 L/min (42 US gpm) ="total loss" 4 L/min (1 US gpm). The "max. allowable loss" is 7 L/min (2 US gpm).

      The pump in the example is acceptable because the actual total loss is less than the maximum allowable loss.

      Note: The crossover relief valves will not be tested at this time due to the risk of exposure to high pressures.

      Reduce control pressure to zero. Disconnect control pressure from signal pressure port (51). Connect control pressure to signal pressure port (54). Vent pressure port (51). This will protect the pressure port for the load sensing spool from hydraulic lock. Repeat Steps 1 through 5.

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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