Flushing Ac System - Reasons/Procedure (TS84-042)

FLUSHING AC SYSTEM - REASONS/PROCEDURE

TECHNICAL SERVICE BULLETIN

FLUSHING PROCEDURES FOR AIR CONDITIONERS ALL MODELS

Model(s): All Nissan Models

Classification: AC84-004

Section: Air Conditioning

Bulletin No.: TS84-042

Date: April 23, 1984

SERVICE INFORMATION

The air conditioning system of any Nissan/Datsun vehicle should be flushed with R-22 flushing agent when any of the following conditions are present.

• When a compressor has failed and inspection reveals metal debris or compressor oil in the compressor suction or discharge ports.
• When examination of the expansion valve inlet reveals significant metal or desiccant particles.
• When a performance test determines that too much oil is in the system.

FLUSHING PROCEDURE

1. If possible, run the system for five or ten minutes at normal idle with the control set at normal cooling and the fan at high speed.
2. Shut off the engine and the A/C systems.
3. Slowly discharge R-12 from the system.
4. Remove the compressor and drain the compressor oil. If there is a considerable quantity of debris in the oil and the oil is significantly discolored, the compressor may require replacement
5. Seal the compressor after draining the oil.
6. Remove and discard the receiver-drier.
7. Remove the cooling unit from the vehicle.
8. Remove the expansion valve from the cooling unit.
9. Drain the oil from the cooling unit.
10. Back-flush the evaporator through the outlet fitting. Flush until clear R-22 flushing agent runs from the inlet fitting. Reflush with R-12 under pressure.
11. Clean and reinstall the expansion valve.
12. Reinstall the cooling unit. Cap the inlet and outlet fittings.
13. With R-22 flush all lines from the outlet fittings to the inlet fitting until the flushing agent runs clear.
14. With R-22 flush condenser through the outlet fitting. Flush until clear flushing agent runs from the condenser inlet fittings. After flushing each unit with flushing agent, flush with R-12 under pressure.
15. Reinstall all lines, using new O-rings.
16. Refill the compressor with new oil to specifications, if the compressor is clean and serviceable.
17. Reinstall the compressor.
18. Charge the system with R-12 vapor and check the system for leaks. Do not run the system.
19. After checking for leaks, slowly discharge the R-12 vapor from the system.
20. Attach the vacuum pump to the system.
21. Evacuate the system for at least two hours-overnight, if possible, which would ensure complete vaporization of the flushing agent.
22. Charge the system with the specified amount of R-12.
23. Check the performance of the A/C system.