Hey guy it has been awhile since I have been on the forums and I hope all is well. I have what I hope is a quick question.
My A/C finally died. I have had it retrofit to r134a but it will not hold a charge. Obviosly it has a leak. Nauturally I want to fix it myself and I am wondering if there is a part in the A/C system that always fails. In other words, is there a place where these normally leak?

 

134a will leak at a faster rate than R12 so even a small leak can loose pressure quickly. I would look at the compressor shaft seal first as that is a dynamic seal prone to wear. Black greasy buildup behind compressor clutch can show a leak as there is oil in the refrigerant. You may be able to replace just the shaft seal as I did on another car. Try here:
http://www.acsource.com/index.asp
It may pay you to have an A/C shop use their sniffer to isolate the leak(s) then fix yourself. If you use dye it will not be visable in the evaporator or behind the condensor. On a 93 it would not hurt, since the system is down anyway to just replace as many o-rings as you can get to. Advance, etc. usually has a set where you'll find close enough sizes to fit. As usual you should replace the receiver/dryer after system has been opened AND pull a vacuum for at least 30 minutes before recharging. Pulling vacuum will also tell you if you have any leaks - just not where.