Usage:
320C U (APA, ALX) EXCAVATORS
Problem:
This is an optional pump flow test to measure hydraulic power for all new 320C excavators. This test may be necessary if dealers have questions concerning the hydraulic power of the 320C.
Solution:
This test is performed by measuring the pump flow at the boom cylinders. This test measures the resultant hydraulic power of the engine and the hydraulic systems.
Illustration 1.
Illustration 2.
Flow meter tool layout
Illustration 3.
Illustration 4.
NOTE: Before starting main pump flow tests, check message display (4) on monitor (3) and alarm lamp (1) on electronic control module (2) for normal operation. If no faults are present, perform the operational checks. Refer to Testing and Adjusting, "Operational Checks".
NOTE: Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.
Reference: Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.
Dispose of all fluids according to local regulations and mandates.
- 1. Position the machine on level ground.
Illustration 5.
Illustration 6.
- 2. Fully retract the stick cylinder rod. Adjust the position of the bucket so that the bucket is parallel to the ground. Lower the boom until the bucket is flat on the ground. Refer to Illustration 5.
- 3. Stop the engine.
- 4. Release the pressure in the hydraulic system. Refer to Testing And Adjusting, "Hydraulic System Pressure - Release".
- 5. Install the following tools in accordance with the flow meter tool layout and the circuit diagram. Refer to Illustration 3 and Illustration 4.
- (15) 6V-9832 Cap
- (17) Pressure tap (right pump delivery pressure)
- (18) Pressure tap (left pump delivery pressure)
- (19) Pressure tap (power shift pressure)
- (23) Right pump
- (24) Left pump
- (18) Pressure tap (left pump delivery pressure)
- a. Disconnect lines (7), (8), (9), and (11) from boom cylinders (13) and (14). Illustration 7 (15) 6V-9832 Cap
Illustration 7.
- b. Install caps (15) to the open end of the connectors at boom cylinders (13) and (14).
- c. Connect portable hydraulic tester (10), test hoses and fittings between line (9) and line (11). Line (11) must be connected to the inlet side of portable hydraulic tester (10). Line (9) must be connected to the outlet side of portable hydraulic tester (10).
- d. Plug lines (7) and (8) with plug (40) and seal (41).
Illustration 8.
- e. Connect a 6000 kPa (870 psi) pressure gauge (20) to the power shift pressure tap (19).
- f. Connect a 60000 kPa (8700 psi) pressure gauge (20) to pressure tap (17) for right pump delivery pressure.
- g. Connect a 60000 kPa (8700 psi) pressure gauge (20) to pressure tap (18) for left pump delivery pressure.
- h. Install multitach (22) on engine (21).
- 6. Obtain a fuel sample and determine the fuel API rating. The fuel API rating will be used in order to calculate the corrected hydraulic horsepower. See Table 5.
 |
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. |
 |
|
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. |
|
- 7. Start the engine.
- 8. Place the machine controls at the following settings: engine speed dial "10" and AEC switch OFF. Refer to Testing And Adjusting, "Engine Performance Test" for engine rpm settings.
- 9. Place the hydraulic activation control lever in the UNLOCKED position.
- 10. Increase the hydraulic oil temperature to the recommended temperature range. Refer to Table 1 and Table 2 for the recommended operating temperatures of the hydraulic oil. It is very important to maintain the recommended hydraulic oil temperature during the test.
- 11. Slowly move the joystick for the boom to the full BOOM RAISE position. Hold the joystick for the boom in this position until the pump flow test is completed.
Portable Hydrualic tester (flow meter)
Illustration 9.
- 12. Turn valve (26) on portable hydraulic tester (10) clockwise until the pressure gauge reads 15700 kPa (2300 psi). Record the pump flow at the pressure specification in Table 1 and Table 2.
- 13. Use the data in Table 1, the data in table 2 and the following formula in order to calculate the hydraulic power.
NOTE: Be sure that all temperature data are indicated in centigrade (C).
NOTE: Power specifications in the above table should read "Equal to or no less than" the values indicated.
- 14. Call your Service Engineering contact if the calculated hydraulic power values are below specifications. Your values can be compared with the factory data. It may be necessary to check the following items after the review.
- * Individual pump flow test
- * Main relief setting and line relief setting
- * Power shift pressure calibration
- * Engine boost
- * Flow meter accuracy
- * Main relief setting and line relief setting
COPYRIGHT 2000 CATERPILLAR ALL RIGHTS RESERVED