Don't know if any of the original posters are still reading this thread but a friend just got a 1979 911Sc and has a York and is not cold. Tentatively we plan to convert to a Sanden and see if that helps. Currently we can't even get the service fittings attached to the equipment due to a lack of clearance from the York to the body. :)

You have a Carrera and hopefully the PO didn't back date the a/c system to a York. You should have a nippondenso if it is still the original compressor. Or maybe a sanden or seiko seiki if it's been upgraded

Best way to find a leak is with an electronic sniffer for freon. Could be a small leak in a location that you may not have access to such as the evaporator core in the smuggler box. The sniffer can determine if the evaporator is leaking by sniffing the cold air from the vents.

I have the same compressor on my 82 Targa.

To attach the pressure gage to the york you have to remove the compressor, attach the gauge, reinstall the compressor and perform the necessary a/c work. Once the work has been completed you need to remove the compressor, detach the gauge and reinstall the compressor.

Oh did I mention that the York uses stem valves instead of shraeder valves? Learn the term backseat and front seat with stem valves.

Take that boat anchor and heave into the Atlantic or Gulf. Only reason why I haven't upgraded my compressor to a seiki seiko or sanden is because the garage queen just have 59,000 miles on her and the a/c still blows ice cold as long as the system is charged.

One thing I learn from my father, who use to be an automotive a/c technician, is that if it not Broke, don't mess with it.

ruf,
what about the dye method? couldn't the shop that performed the service in the first place have checked it before filling? it's normally about a $25 charge to do a leak test..i'm not familiar with the electronic sniffer method. sounds like finding if he has a leak is the first place to start..ought to upgrade to barrier-style a/c hose too if not already in place.
ryan

Hey guys, thanks for the prompt thoughts. I will keep the forum posted on whatever progress we make. :)

I replaced a failed Nippodenso with a Sanden "rotary" (purists stay away), and have had great cool days in a cab since then. I usually have to add 1 can of r-134 in May and one in August as I think the hoses leak it away. I see no oil spray evidence at any connection and have had them checked by a local Porsche shop that handles AC as well, so what they tell me is that the stock hoses leak r-134 more than r-12. Is that true or am I being fed a steaming pile of ?????

i think the size of the r-134 molecule is indeed smaller than that of r-12..this is probably a true statement.
ryan

Where you're being fed a pile of steaming ???? is that the Sanden is a rotary compressor. It's not. It's a five-piston wobble plate compressor. The only true rotary is the Seiko-Seiki.

I would love to have a Bell47. I assume yours has a 6-Cylinder Franklin? They are sitting around $75K these days aren't they? Of course I have to learn to fly helicopters first. I have had a lesson in an R-22 and the Army UH-60 Simulator. My friend and I converted the Cessna 421 to a Sanden from a york and it works great. Our Evaporator is up front and the Condenser is in back and we have a bunch of a/c hose too.

My '79 SC had a bad leak in the low pressure hose near the right jack point (along with partially smashed oil lines) due to some previous a-hole jacking the car in this area. I spliced the hose, replaced the drier, evacuated the system and converted to 134 about 2 1/2 weeks ago and thus far all is well w/ vent temps at 46 degrees in mid 80's temps (going down the road @ 60mph). Time will tell if my DIY AC repair/conversion will last or not.

The point here being that the stock hoses and components should not leak down in ONE DAY no matter which refrigerant is used. You obviously have a fairly bad leak somewhere. It just may be bad enough to find w/ Snoop or soapy water if your sytem is still pressurized. (that is basically how I found my hose leak)

If the leak is in the evaporator you won't be able to see the dye since the evaporator is in the smuggler box in a plastic housing.

The electronic sniffer is the best way to determine if an evaporator is leaking, since most evaporators are located behind the dash and access to the evaporator is very limited.