dr bob

The hose closest to the camera, the one with the big purple smear on it, is from the automatic transmission hardline to the cooler in the radiator on the passenger side. It's unlikely that it's leaking refrigerant. Meanwhile, as Griff points out, it's adjacent to the original-appearing purple-dye-stained low-pressure hose. That hose is easy to remove for local rebuild with barrier hose, or you can find one already built from our regular suppliers, as well as from non-sponsoring vendors like Griffiths. The "other" compressor hose is a bit more of a challenge, since it goes around the radiator and condenser. From the receiver-drier, the line that connects to the hard pipe on the right-side fender wall needs to be serviced (new hose, crimped connection) in place.

For now: Carefully clean that whole area with a good detergent wash and hose rinse. That should get rid of the old oil and dye on the hoses and the area. Then drive for a short while with the AC on, and inspect again with the UV light see if you can see the sources of the leaks.

For those playing at home, it seems a common practice for folks to put tracer dye in the system. Then when the system has leaked down, they wonder why they didn't see any dye traces. Hint: You need a good UV light source, a dark inspection area, and some special glasses if there's much stray ambient light. Then suddenly it looks like the wild south african purple-dye flinger did a war dance in the engine bay. Do your leak checking early after the system is worked on, so the dye is still only close to where it's leaking out. After the airflow from the fans etc has spread the dye-laden oil around everything, all you know is that you have a leak somewhere.

decampos

Thanks for your reply Dr Bob. The purple smear is glare from the UV light I was shining. I have cleaned the area as you recommended and had it running for a while. It appears that this is the only leak but I assume it's only a matter of time (minutes) before the other one ruptures also as they're all the same vintage.

ugh, what a pain. Am I right in thinking that before I mess around with installing a new hose (or removing the hose to have it repaired) I have to take the car to some facility that can remove the refrigerant?

+1. It would have been hard to find an AC leak in a 32 year old caked up engine bay without the UV dye and light.

dr bob

You'll want to evacuate and start over, including the new hoses this time.

I bit my tongue and bunched up my typing fingers when you shared that you were going to stick with the PAG oil in the system. I stronly recommend that you take the opportunity to flush the two heat exchangers of the PAG and the mineral oil residue in there, drain and replace the oil in the compressor with POE, and replace the drier again before adding the right amount of POE oil. Every nce in a while there is a miracle story where PAG oil worked for a while in an unflushed system; Much more prevalent are the stories of subsequent disaster where the compressor, starved for lubrication because the new PAG oil mixed with old mineral oil and turned to jelly, finally started to grind itself into a fine grey aluminum powder that contaminated the whole system and took a LOT more work to restore. The cost of commercial recovery of a system that's self-destructed that way can easily be enough to total one of these cars, in the eyes of an insurance adjuster. You should think of it the same way.

decampos

Thought I'd put this thread to bed (again) as the a/c is working once more.

I balked at the cost for new a/c hoses and managed to find a local place that can rebuild lines an order of magnitude cheaper than porsche prices.

Rebuilt low pressure hose for 55$:





As I had the compressor out again, it made sense to do a better job of flushing the system again and I'm glad I did. Here's the kind of thing that was now circulating in the system (two different oils clearly not getting on)
(the white residue is candle wax as the glass originally contained a scented candle)



All works good and currently no leaks. I hope this time it stays that way. Thanks again for all your helps.