I have a 1990 Mazda Miata, and the AC is not working. It has been switched over to R134a. I took it to a mechanic to have it recharged a few weeks ago. He said that one of the o-rings was cracked and so it was leaking around that. He filled it up and put some stop leak in it and for awhile it seemed to work fine. Then it stopped blowing cold air. I took it to a jiffy lube just to have the level of coolant (correct term?) checked. The person there told me that it was very low and was leaking around the valve stems. I tightened the valve stems and re-filled it. After 24 hours it had stopped blowing cold air again. I got a price quote on a new compressor and it is about $500.
So - my question is this - should I just put a new compressor in or is there something cheaper I could try first? I’m not incredibly knowledgable about cars, but I am willing to try doing simple things myself.