951Badger

My new 1988 951 was checked out a Porsche dealership before I bought it and had it shipped to me.

One thing they said they found was that an air conditioning hose was leaking and needed replacing as alot of the Freon leaked out and a/c did not blow cold. They quoted about $600 for the fix and re-charge.

Took it to MY mechanic here in town. He said he could find no leak but Freon needed two cans. I said "how could it need som much if no leak?" He said "If the car sits long enough, you can temporarily lose seal and get a slow leak overtime".

This car DID sit for a LOOOOONG time. It did only 100 miles in the last two years and only about 3000 miles in 10 years. Currently has 38,000 miles on it.

Is my mechanic right or did he miss a leak????

Help!!

elf89

The PO of my 944 didn't use and had never recharged the AC. He got some R12 on e-bay and had it done as part of the sale. It's been fine for a couple months now.

My understanding is that the freon has some sort of oil in it that lubricates the seals. If it's not used, even over a winter, the seals dry up and you lose the charge. The advice I've been given is that if you store it over the winter, you still should run it and run the AC once a month or so.

My plan is to try to keep this charge as long as I can and then decide whether it's worth converting to R134.

Quickbeam

I've heard the seal comment before but thru some research I also found that the refrigerant molecules are smaller than the pores in the hoses. Over time the refrigerant escapes no matter what you do. Its apparently normal to charge your AC every few years.

bpp944

It's my opinion that your mechanic is correct, If your car has sat for as long as you've indicated, you probably have a leaky O-ring.

When they test AC systems they usually put a dye in the system, then pressurize they system. they're supposed to do a visual inspection looking for the dye around the connection points and the condenser. Some of the better shop's even use a sniffer that can detect a leak in hard to find places. (Like under the dash board).

I believe that most of the new refrigerant's contain a lubricant for the O-ring to remedy this very problem, but don't take my work for it -ask your mechanic.


Good luck with the AC,
B

IceShark

I concur on the seal dry out leak if not run and would expect it on a car used as little as that. Being in Minnesota there is a list of car facts your father is supposed to teach you. Running the air con once a month even if it is 30 below zero is one of those facts.

I can believe the molecule migration theory also. You would be surprised at what can migrate through even steel.

threesticks

Hello 951Badger: Who is your mechanic here in Phoenix? I've good experiences with Don Jackson Ent. and Stuetguart Southwest.

Just curious, Steve Frew.

951Badger

Thankss to all for the advice. That helps to ease my mind a bit.

Steve:

I've used Stuttgart for awhile now (with my last two Porsches) and also use a guy at a place called Technodyne about a block from Stuttgart. His name is Chris Cervelli and he's a friggin' genius with 951's.

Thaddeus

My Volvo does the same thing, once a year (and I run the thing once a month also). Stuff leaks out, 3 different shops can find no leak with dye or sniffer, they replace random o-rings and so on in hopes of catching it, recharge it, it works for a year...

I'm going to convert the Volvo to r134a if I can... I'd rather not know that it's leaking r12 incrementally, and I can just shoot a can in once a year myself after that...

Thaddeus