rgs944

OK that was not a serious question but I removed my seat today to fix the seat switch and found these lines very loose. One thing that puzzles me is that when we charged the AC last year it held a vaccum. Now it seems to be low on freon again and not working. Is it possible that it is only leaking when the rear AC is turned on? A mistake we did make is charging the system without the rear AC running so I knew that it was not completely full to begin with. Also are these fittings compression fittings or do they have O rings?

Speedtoys

Finger tight = not tight.

They should have O rings as well..a couple 'O 999 707 284 40's IIRC.

rgs944

Any ideas on how these lines would have worked loose or were just left loose by someone at somepoint? It is hard to believe they held anything at all with only being finger tight.

ammonman

Threads might not have been lubed the last time someone put it together. Also, there is some hose in those two lines where they run up the inside of the rear console. Just did my A/C and had both rebuilt. The liquid line outer jacket was split and there was snot all over under the console like someone shot a can of leak sealer into the system instead of finding and fixing the leak.

Mike

griffiths

If the system is empty (no refrigerant), replace the o-rings,
put a dab of loctite on the threads:

5/8"x18 threads are 10-14 ft lbs
3/4"x16 threads are 24-28 ft lbs



(section 87)

rgs944

See that's where I do not know what to do. I went through all the trouble of filling it last year and I believe it did start up once this year. That is why I think it is only leaking when the rear AC is on. Now that the fittings are tight I am not sure I want to take the chance of opening it up and going through the whole vac process again when a simple recharge might set me up. I have about 25lbs of R-12 that is primarily dedicated to the 928 so I think it might be worth a fill and try to get me through the summer.

fraggle

Note: Rear AC is not completely isolated from the system when it is "off".

dprantl

When the ignition is off, the rear A/C solenoid is open so the system is continuous. When the ignition is turned on and the rear A/C controls are set to off, the rear A/C solenoid is closed. The only other time the rear A/C solenoid is closed is when the rear anti-freeze switch tells it to. If you have a refrigerant leak somewhere in the rear A/C system, it will not only leak when you have the rear A/C on, it will also leak when the car is not being driven.

Dan
'91 928GT S/C 475hp/460lb.ft

rgs944

Thanks Dan, that is why it is so confusing. How could the system seem to hold a good vac when the tech had it on the machine last summer. It does not make any sense that with those fitting so loose it would have held anything. The other mystery is how they could have come so loose to begin with.

jeff spahn

Use Nylog blue when you put the o-rings in.

SteveG

I'm not a technician, but I do have that certificate , but I don't see how you could have had pressure; what's worse, it would have ambient air and moisture in the system. If it were mine, and I thought the seals were OK, I would evacuate, make sure it held vacuum and refill. If you could take it to a recovery station, and give them the R12 you have to refill it, so much the better, but I doubt there is much R12 in it.

Speedtoys

Heat expansion, vibration...they cane lose, happens. I had lose ones in places on my car, otherwise..worked fine when I bought it "not working".

A seal pulls into a vacuum..so ya, that makes sense too.