You don't need lubricant. If it is that tight but still leaks you probably have it cross threaded. It should screw on easily. If it needs lube, there is something wrong. Don't add any o-rings. If there wasn't one there before then don't add one.

For the compressor leak, the two o-rings are the only seal there is and the only one that is needed. You need to put refrigerant lube on the o-rings then tighten the bolt.

Answered by promechanic (expert)
556 answers provided

It took me over 2 hrs initial to unscrew evaporator from accumulator. I used a lot W40 and b blaster. I noticed a lot of black dirt or something stuck threads. Before I put back on I tried to scrub threads with wire brush with W40 to take some that stuff off, I guess I didn't do a good job. Is there a cleaner that can help remove dirt on threads?

Response from roycar71
27 questions asked

The threads don't do the sealing/ they merely pull the 2 pipes together so the O-ring can seal. The accumulator uses an O-ring and the connection at the compressor uses special rubber washers.
If you damaged the threads on the accumulator when working there, you will likely be replacing and evaporator now.

Answered by Wrenchtech (expert)
14,726 answers provided

Before installing new accumulator. There wasn't o-ring on tube going into accumulator from evaporator. There was one on accumulator to compressor. As for the compressor, I have 2 or 3 types that came with it. I just used the o rings on tube. How do I know which washers to use for compressor.

Response from roycar71
27 questions asked

You use the ones that fit the hose.

Answered by Wrenchtech (expert)
14,726 answers provided

there is a inlet tube with screw nut that goes into the accumulator. It seems I have it as tight as I can get it. Is that screw nut suppose to move back and forth on tube?

Response from roycar71
27 questions asked

Definitely not. You have probably cross threaded it and now you'll be replacing the evaporator. I warned you a few times that you shouldn't be tackling this job because it will cost you more to learn the hard way.

Answered by Wrenchtech (expert)
14,726 answers provided

I am not talking about screw into accumulator. It is the screw nut on tube. It slides back in forth. but connection that screws into accumulator is tight.

Response from roycar71
27 questions asked

It appeared to be like this when i took it off. It now more loose since i use some wd40.

Response from roycar71
27 questions asked

If it's loose in any way it will not hold refrigerant and there is no way to repair the threads except replace the component.

Answered by Wrenchtech (expert)
14,726 answers provided