Compressor Leak Testing

TOOLS REQUIRED
^ J 39893 Pressure Testing Connector
^ J 39500-B R-134a A/C Refrigerant Recovery, Recycling and Recharging System (ACR4)
^ J 34992 Compressor Holding Fixture
^ J 39400-A Leak Detector




1. Install the J 39893 on the rear head of the compressor.
2. Using the J 39500-B, attach the center hose of the manifold gauge set on the charging station to a refrigerant drum standing in an upright position.
3. Connect the charging station high and low pressure lines to the corresponding fittings on the J 39893.
The suction port (1) (low-side) of the compressor has a large internal opening. The discharge port (high-side) has a smaller internal opening into the compressor. The discharge port (2) (high-side) also has a deeper recess.
4. Open the following controls on the charging station in order to allow refrigerant vapor to flow into the compressor:
^ The low pressure control
^ The high pressure control
^ The refrigerant control
5. Use the J 39400-A in order to inspect for leaks at the following locations:
^ The pressure relief valve (5)
^ The rear head switch location
^ The compressor front head seal
^ The compressor rear head seal
^ The center cylinder seal
^ The through bolt head gaskets
^ The compressor shaft seal
6. Turn OFF the low-pressure control and the high-pressure control on the charging station.
7. Perform the following steps if an external leak exists:
7.1. Perform the necessary corrective measures.
7.2. Inspect the components for leaks again in order to verify that the leak is corrected.
8. Recover the refrigerant.
9. Disconnect both hoses from the J 39893.
10. Add 60 ml (2 fl oz) of new PAG lubricant to the compressor assembly.
11. Slowly rotate the complete compressor assembly (excluding the crankshaft and the drive plate hub) several turns in order to distribute oil to all of the cylinder and the piston areas.
12. Install a M9 x 1.25 threaded nut on the compressor crankshaft it the drive plate and clutch assembly are not installed.
13. Use a box-end wrench or socket and handle in order to rotate the compressor crankshaft or clutch drive plate on the crankshaft several turns. Performing the above action will ensure piston assembly to cylinder wall lubrication.
14. Using the J 39500-B, connect the J 39893 to the test plate high-side connector.
15. Using the J 39500-B, connect the charging station low-pressure line to the low-pressure port of the J 39893.
Oil will drain out of the compressor suction port (1) if the compressor is positioned with the suction port downward.
16. Attach the compressor to the J 34992.
17. Mount the compressor in a vise in order to place the compressor in a horizontal position.
18. Use a wrench in order to rotate the compressor crankshaft or the drive plate hub ten complete revolutions at the speed of approximately one-revolution per second.
Turning the compressor at less than one-revolution per second can result in a lower pump-up pressure. Low pump-up pressure may disqualify a good pumping compressor.
19. Observe the reading on the high-pressure gauge at the completion of the tenth revolution of the compressor.
The pressure reading for a good pumping compressor should measure 690 kPa (100 psi) or above. A pressure reading less than 620 kPa (90 psi) indicates one or more of the suction and/or discharge valves have an internal leak or an inoperative valve.
Perform the following procedure if one of the valves are leaking or inoperative:
19.1. Recover the refrigerant.
19.2. Disassemble the compressor.
19.3. Inspect the compressor for the cause of the leak.
19.4. Repair the compressor as necessary.
19.5. Reassemble the compressor.
19.6. Repeat the pump-up test.
19.7. Test for external leaks
20. Recover the refrigerant from the high-side.
21. Remove the J 39893.
22. Tilt the compressor with the compressor suction port (1) and the discharge port (2) positioned downward.
23. Drain the PAG lubricant from the compressor. Allow the compressor to drain for 10 minutes.
24. Refill the compressor with the proper amount of PAG lubricant.
Pour the PAG lubricant into the suction port (1).
25. If further assembly or processing is necessary, install a shipping plate or the J 39893. The shipping plate or the J 39893 prevents the following materials from entering the compressor until the compressor is installed:
^ Air
^ Dirt
^ Moisture