I have been planning this project for more than half a year. It begins tomorrow. The stage is set:


I have laid forth my action plan here. I shall no longer be a victim of the Kentucky summer heat.

 

I don't see anywhere where you initially test the system for leaks.

It is quite common for the evaporator to develop a leak on the s cars.

I highly recommend you rule out evaporator issues before putting in the time, effort, and money.

 

He mentions pulling a vacuum and checking for leaks.

 

That's good advice, and the initial Leak check isn't mentioned because it has already been completed. the system was fully charged and functioned well for about 1 day.

The UV dye was found only at the compressor, and as I understand the gm compressors were also known to fail.




Of course, there is always a chance that the evaporator core leaks in a manner that I couldn't detect.

 

Interesting....

I am no AC guru by any stretch of the imagination, so I'm asking the following in an attempt to be both helpful and to learn.

Those look like o ring failures (?)
What I don't understand is that If one line is the high side and the other line is the low suction side, how would they both be expelling refrigerant with dye to that extent? If the low side of the compressor is pulling a suction, should there be any positive pressure at that connection allowing or pushing refrigerant out past the o-ring? Or do I have my pressure differential physically backwards in my mind. (As in the pressure is zero at the compressor where the suction line attaches but is negative in the line, so the pressure differential from line to compressor is say -10 to 0 which is positive.....?? But then how does the low side Port read positive if this is the case? Or is that a vacuum pressure and I didn't look at the gauge carefully enough?

Just trying to understand The finer points of AC. Not sitting here throwing rocks. I want you to succeed, not only for you, but for me. My 95 SC2 hasn't had fully functional air in a decade. Very few people take the time to restore AC on these turds, so when I see someone making the effort and putting out the $, I try to help in whatever way I can while also learning something if possible.

For the benefit of others, it would be great if you could take some sort of photo corresponding to each of that list of steps. Nothing elaborate. Maybe add " watch out for" comments where applicable. The goal is a complete sticky on how to perform what you're doing. Possibly a tool inventory for the entire job as well if possible.

Good luck..... please keep us informed of your progress.

Thanks

Derf

 

There are definitely some O-ring failures and additionally some internal compressor gasket failures (indicated by the leaks on the compressor itself located away from the hose connections). There actually are gasket rebuild kits for this model compressor, but they are quite complex and require special tools to disassemble... its just easier and less risk to replace it.

I suppose (assuming there are bad o-rings) that the reason the compressor would leak out of the suction side is that when the compressor clutch is not engaged, or is not active or when the car is not running, then the negative pressure on the low side returns to a positive pressure? Not exactly sure...

Anyways, I decided to check the evaporator core drain tube one last time for UV dye before beginning this morning, and I noticed two other problems that need to be taken care of first (dry-rotted line from Charcoal Canister to the EVAP Purge Solenoid and a leaking power steering hose), so the AC project will be delayed probably until Monday.

 

Seems like a reasonable explanation. The pressures do equalize between the high and low side when it is not actually compressing, so indeed there is nothing forcing it out. At the same time, If there is a leak at the o-ring, it will eventually seep.

Glad my nagging uncovered some collateral things now rather than later.

 

I am having difficulty finding a good resource for where exactly the Evaporator Core Drain Tube is located. I am think its here, but can someone please confirm?


Just want to be sure.

 

@Dude can you help this gentleman out?

 

That's where the drain is on my 97.