Good afternoon all,
The A/C in my 1992 960 stopped working quite some time ago. Roughly 5 years or so, actually. At time what happened was that after 2 hours of highway driving I pulled off the road and heard a bad whirring noise. It was coming from the compressor. Turning off the a/c makes it stop. So my assumption is it's the clutch (unless it's internal).

The questions - it's pretty much not been used for most of the past 5 years or so, but I'd really love to have it back. I'm pretty certain the charge is lost. What's the best possible course to take to check the existing system and/or get it back up and running again?

Thanks in advance,
John

John, if your A/C shop is any good, they will test the system with nitrogen or some other inert gas. Pick your shop carefully - I do most of my own work but for A/C I took it into a local place and along with the leak they (correctly) identified, they also wanted to replace the drying unit and the condensor - both brand new. No thanks. . .
--
Tony - 1990 745 - 225K Regina Non-turbo

Tony, thanks for the input. I'm in a bind right now of choosing between the shop of the long-time family friend, or perhaps an AC specialty shop. I'll get that figured out soon enough. Knowing that a non-refrigerant test is possible is good help so that I can explicitly ask for it.
Thanks again,
John

Steps:
-fix what's wrong (new compressor?)
-flush system of oil and debris (have a shop do this)
-test for leaks (ditto)
-convert to R134 using Volvo OEM conversion kit, including a new receiver dryer
-vacuum and refill (again, a shop)
-enjoy cool air.

Thanks for the really speedy response!

Please forgive my innumberable questions, but a/c system is really my weakest point of understanding. This sounds like a good plan, although I worry about what might happen at the "check for leaks" step. In the check for leaks, other than the numerous tubes & connectors under the hood, are there many additional (hidden?) points that might fail? I guess I'm asking what kind of potential the core has for a failure point, since that would be both costly and time consuming?

I'm also wondering if it would be a bad idea to leak-check the system before changing out the compressor? Is it possible to leak-check with a non-refrigerant fluid, thereby cutting down the refrigerant waste in the check? I'll have a local shop do the points that you mention they should do, I'm just hoping to understand as best I can before going to them.

Thanks again,
John

Dear John,

Good p.m. I'm not an aircon expert. There are some brickboarders, with truly awesome expertise, and I hope they'll follow-up.

To detect leaks, a fluorescent dye is mixed into the a/c system oil. If there are leaks - even minute ones - they can be spotted with a black light. The dye glows under black light.

This is useful for leaks in all "in plain sight" components (hoses, tubes, fittings, etc). The evaporator, which is located under the dash, is hard to get to. To access the evaporator, most of the under-dash equipment (radio, climate control unit, storage tray, glove box, etc.) needs to be removed. This is costly because it is time consuming.

The system can be pressurized with air. If the pressure bleeds down, then there are leaks. It some fluorescent dye is introduced, the leaks can be found. If, after finding/curing obvious leaks, the system will not hold pressure (or hold a vacuum) the evaporator will need to be checked.

Hope this helps.

Have a Safe and Enjoyable Fourth of July Holiday.

Yours faithfully,

spook

Hi spook,
Thanks for the help and info. I have this fear of something being wrong with the evaporator, which is why I'm trying to get as much info as I can. Last car I had ('84 760) I had to go in and change out the heater core, so I'm guessing that the evaporator on this 960 would be similar, if not more involved. I've got no trouble in doing as much labor as I can safely do myself, so hopefully that'll keep my costs down. Info such as knowing the system can be air-pressurized for leakage is good. I'm hoping whatever shop I go to will be accomodating. Thanks again for the tips,
John