349F and 352F Excavators Hydraulic System Caterpillar

Specification

Illustration 1	g02377942
P-Q characteristic curve

Note: Specifications for output flow rates are based on an engine speed of 1800 rpm. To attain more accurate test results, measured flow should be corrected with the following calculation.

Note: Specifications for output flow rates are based on a power shift pressure at the pump of 2700 kPa (392 psi). The output flow rate changes approximately 10 L/min (2.6 US gpm) for each 100 kPa (14 psi) of power shift pressure in the lower range of the constant horsepower control. The output flow rate changes approximately 3 L/min (0.8 US gpm) for each 100 kPa (14 psi) of power shift pressure in the higher range of the constant horsepower control.

Note: If the output flow rate of the pump is not within the specification, disconnect the negative flow control line from the pump that is being tested and perform the test again.

Note: Flow measurements must be done only during pressure rise.

Introduction

This test measures individual pump flow at the pump. Each pump is tested individually for output flow at specified pressures. The pump that is not being tested is not under load and the pump remains at low-pressure standby.

Preliminary Test

• Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust"

• Testing and Adjusting, "Solenoid Valve (Proportional Reducing) - Calibrate (Power Shift Pressure)"

• Testing and Adjusting, "Solenoid Valve (Proportional Reducing) - Calibrate (Negative Flow Control)"

Required Tools

Illustration 2	g02571852
Tooling (A) 198-4240 Digital Pressure Indicator Gp

Illustration 3	g02535237
Tooling (C)

Illustration 4	g02146945
Tooling (D) (Flow meter tool layout)

ReferenceRefer to Tool Operating Manual, NEHS1087 for operating instructions for the 348-5430 Multi-Tool Gp .

Note: Use Software License Card, NETG5049 with part number 348-5430 Multi-Tool Gp .

Machine Preparation

Illustration 5	g02146943
Flow meter tool layout Tooling (D) (4) Delivery line for the drive pump (5) Delivery line for the idler pump (6) Bolt (7) Washer (8) Half flange (9) Seal (10) Makeup line (11) Seal (12) Elbow

Drive Pump

Note: Perform the test for the drive pump and the test for the idler pump one at a time.

Illustration 6	g02145888
Pump compartment (1) Pressure tap (delivery pressure for the drive pump) (2) Pressure tap (delivery pressure for the idler pump) (3) Pressure tap (power shift pressure) (4) Delivery line for the drive pump (5) Delivery line for the idler pump

1. Position the machine on level ground.

2. Stop the engine.

3. Release pressure in the hydraulic system. Refer to Testing and Adjusting, "System Pressure - Release".

4. Attach 311-1362 Vacuum Cap onto the hydraulic tank. Attach an air supply hose onto the assembly. Apply 276 to 414 kPa (40 to 60 psi). This procedure will pull a vacuum on the hydraulic system.

5. Install the following tools in accordance with the flow meter tool layout. Refer to Illustration 5.

   1. Disconnect delivery line (4) from the drive pump.

   2. Install seal (9) , half flanges (8) , and blocking cover (D18) to the end of the delivery line with bolts (6) and washers (7) .

   3. Assemble and install seal (D17) , adapter (D16) , seals (D4) , fitting (D12) , seal (D11) , plug (D10) , and fitting (D5) on the drive pump by using half flanges (D15) , bolts (D13) , and washers (D14) .
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   Illustration 7	g02146948
   Right swing motor (top view) (10) Makeup line (11) Seal (12) Tee

   4. Disconnect makeup line (10) from tee (12) at the right swing motor.

   5. Assemble and install seals (D20) , tee (D21) , elbow (D19) , seal (D4) , and fitting (D5) to tee (12) at the swing motor.

   6. Install seal (11) and makeup line (10) to tee (D21) .

6. Remove 311-1362 Vacuum Cap and install the filler plug for the hydraulic tank.

7. Connect portable hydraulic tester (D) and test hoses between coupling assembly at the drive pump and coupling assembly at the swing motor.

8. Attach a 41,368 kPa (6,000 psi) pressure sensor to pressure tap (1) for delivery pressure of the drive pump. Attach a 34,450 kPa (5000 psi) pressure sensor to pressure tap (3) for power shift pressure.

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Illustration 8	g02404480
Proportional reducing valves (negative flow control) (13) Connector (14) Connector (15) Proportional reducing valve for "NFC1" (16) Proportional reducing valve for "NFC2"

9. Disconnect connector (13) from proportional reducing valve (15) .

10. Install tooling (C) on the engine to monitor engine speed.

Idler Pump

Note: Perform the test for the drive pump and the test for the idler pump one at a time.

Illustration 9	g02145888
Pump compartment (1) Pressure tap (delivery pressure for the drive pump) (2) Pressure tap (delivery pressure for the idler pump) (3) Pressure tap (power shift pressure) (4) Delivery line for the drive pump (5) Delivery line for the idler pump

1. Position the machine on level ground.

2. Stop the engine.

3. Release pressure in the hydraulic system. Refer to Testing and Adjusting, "System Pressure - Release".

4. Attach 311-1362 Vacuum Cap onto the hydraulic tank. Attach an air supply hose onto the assembly. Apply 276 to 414 kPa (40 to 60 psi). This procedure will pull a vacuum on the hydraulic system.

5. Install the following tools in accordance with the flow meter tool layout. Refer to Illustration 5.

   1. Disconnect delivery line (5) from the idler pump.

   2. Install seal (9) , half flanges (8) , and blocking cover (D18) to the end of the delivery line with bolts (6) and washers (7) .

   3. Assemble and install seal (D17) , adapter (D16) , seals (D4) , fitting (D12) , seal (D11) , plug (D10) , and fitting (D5) on the idler pump by using half flanges (D15) , bolts (D13) , and washers (D14) .
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   Illustration 10	g02146948
   Right swing motor (top view) (10) Makeup line (11) Seal (12) Tee

   4. Disconnect makeup line (10) from tee (12) at the right swing motor.

   5. Assemble and install seals (D20) , tee (D21) , elbow (D19) , seal (D4) , and fitting (D5) to tee (12) at the swing motor.

   6. Install seal (11) and makeup line (10) to tee (D21) .

6. Remove 311-1362 Vacuum Cap and install the filler plug for the hydraulic tank.

7. Connect portable hydraulic tester (D) and test hoses between coupling assembly at the idler pump and coupling assembly at the swing motor.

8. Attach a 41,368 kPa (6,000 psi) pressure sensor to pressure tap (2) for delivery pressure of the idler pump. Attach a 34,450 kPa (5000 psi) pressure sensor to pressure tap (3) for power shift pressure.

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Illustration 11	g02404480
Proportional reducing valves (negative flow control) (13) Connector (14) Connector (15) Proportional reducing valve for "NFC1" (16) Proportional reducing valve for "NFC2"

9. Disconnect connector (14) from proportional reducing valve (16) .

10. Install tooling (C) on the engine to monitor engine speed.

Test Procedure

Note: Perform the test for the drive pump and the test for the idler pump one at a time.

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To prevent personal injury or equipment damage from failure of the hydraulic test equipment or associated circuit components because of blocked pump flow, make sure that the test equipment valves are fully open before starting the engine.

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To prevent personal injury and/or equipment damage from failed lines or components while the hydraulic test equipment is returned to the open flow position, slowly open the hydraulic test equipment valve while monitoring the pump flow. If pump flow does not increase as the valve is opened, shut the engine off and determine what is preventing the pump from upstroking.

1. Start the engine.

2. Increase the hydraulic oil temperature to 55° ± 5°C (131° ± 9°F).

3. Place the machine controls at the following settings: engine speed dial "10" and AEC switch OFF. Refer to Testing and Adjusting, "Engine Performance - Test (Engine Speed)" for engine rpm settings.

4. Enter the service mode.

   1. Input the password "9992".

   2. Select "Override Parameters".

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Illustration 12	g02377538

5. Set the engine speed to 1800 rpm.

6. Set the power shift pressure to 2700 kPa (392 psi). Confirm the power shift pressure setting at pressure tap (3) .

7. In order to perform flow measurements for either one of the pumps, the other pump must not be under load.

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Illustration 13	g02599896
Portable hydraulic tester (flow meter) (D1) Portable hydraulic tester (flow meter) (17) Valve

8. Turn valve (17) on the portable hydraulic tester clockwise. Record pump flow at each of the following pressures in Table 1. Use the pressure sensor at pressure tap (1) to monitor the delivery pressure of the drive pump or use pressure tap (2) to monitor the delivery pressure of the idler pump.