Stewart DIBBS wrote:

> "Greg Campbell" <ggeonerdd@ccoxx.nnett> wrote in message
> news:Udwbg.87360$TK1.44843@fed1read06...
>
>>It's May in Tucson, and my AC is on the fritz.
>
>
> Leaks occur in two common places: round the hose O-rings and through pin
> hole corrosion in alloy parts.
>
> Less commonly it leaks through the wall of old R12-type hoses.
>
> Your 92 was built for R12 refrigerant When the compressor was replaced, the
> system may have been updated to R1134a, which requires new O-rings. If this
> was done, there should be an update sticker somewhere, typically on the
> inside of the hood.

It was still fitted with the R12 valve with no 134 sticker in sight.

> Locate the high pressure valve on the tube that comes from the condensor in
> front of the radiator. Press this for a moment. If you get a loud, sharp
> SHHH sound, the pressure is OK. If you get a quiet, soft shhh, you still
> have residual pressure, and you can top up the system with Duracool or
> similar compatible refrigerant for about $20

Got a pressure guage. It drops daily, so I seem to have a very real
leak to find and fix.

> If you have no residual pressure, then you need to take the car to an A/C
> shop because you can't do this yourself unless you have the right
> (expensive) equipment. Have them do the following.
> a) replace all O-rings with R1134a compatibles.
> b) if the system was still R12, pull the compressor off, replace the oil and
> fit the necessary R1134a fittings, and replace the drier cannister.
> c) evacuate the system (this is what you can't do yourself) to test for
> leaks. If the hoses themselves are leaking, you will have to get new hoses.
> d) refill with R1134a.
>
> Get a quote from several shops. It should be in the $200 or so plus parts
> range. No shop can tell the hoses are bad without running tests.

Heh. That $200 thingy is what I was hoping to reduce!

I know I can't properly evacuate, test, and recharge the system. I do
plan to go over the whole system, chasing the coolant leak and replacing
any tired parts, seals, o-rings, etc. as I go.

Thanks for the info!

-Greg