So I recently added new a/c lines when the lines were leaking. So I replaced them and I noticed that I have a big leak from the fitting that goes to the radiator. This leak obviously wasn't there before the new lines. I re- tightened them and it continued. I then pulled off the line from that fitting and noticed that the old o-ring was stuck together with the new o-ring. I took of the old one and the leak continued. Does this fitting need two o-rings one on the line and one on the fitting. I am really confused. Please help.

 

Only needs one O-ring.

Replace the one that had got doubled up. Put in a completely new one. If that doesn't fix it, then one of the metal parts is damaged somehow and will have to be replaced.

 

Ok, I will change out the o-ring and hope everything goes good. Thanks.