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* Reply by Jack D. Russell, Sr. <jackru$$ell2@notmail.com>
* Newsgroup: alt.autos.porsche.944
* Reply to: All; "William B Noble (don't reply to this address)"
<nobody@nowhere.com>
* Date:Sun, 16 Jul 2006 07:29:59 -0400
* Subj: Re: My 944 Air Con is working....I nearly dropped dead with
shock!
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WBd> having done exactly that on several 944s, I'll suggest that you see
WBd> how well it works in a week, and in 6 months - seals that didn't
WBd> leak before will start to leak, at least that's been my experience
WBd>
WBd>
WBd> On Sat, 15 Jul 2006 00:48:26 +0100, "Howie"
<djhowie@djhowie.plus.com>
WBd> wrote:
WBd>
WBd>> Hello everyone,
WBd>> Excuse me for bragging, but I can't contain myself any longer. Ive
WBd>> had my car for nearly 10 years and lived with the fact the air con
WBd>> doesnt work ( like every other Porsche 944 owner). Well guess
WBd>> what, I decide to fix the air con on my other car, and when I took
WBd>> the car to the garage, the owner moved his car to make way for
WBd>> mine, and his was a 944 turbo. So as you can imagine, the first
WBd>> thing I asked him about was the air con. "Of course mine works" he
WBd>> said, so I quickly told him he had another job on his
WBd>> hands. Anyway to cut a long story short, he vacuumed out the R12
WBd>> gas, pressurised the system to check for leaks. There weren't any.
WBd>> So he changed the service nozzles over to the new retrofit R134a
WBd>> nozzles and gassed it up to see if the compressor was seized.
WBd>> Mixed in with the gas was a mixture of dye and esther lubricant
WBd>> which is compatable and will mix with the original PAG lubricant
WBd>> in the compressor. Bingo, everything sprung into action and worked
WBd>> like a dream.  I could have had this working 10 years ago if I
WBd>> hadn't listened to all the so-called experts who told me i was
WBd>> wasting my time and my money. As it turns out the whole thing cost
WBd>> me less than £100. So go on, give it a go.....it might just work,
WBd>> it did for me.

I did the same to the working R12 A/C system in my 944 back in 1997, as
R12 was getting outrageously expensive. I'd heard all of the stories
about how 134a wouldn't cool as well, would leak, etc. I didn't change
any seals/o-rings etc., just the adapter. Here it is almost 10 years
later and the A/C still works/cools just as well as ever. I do have to
add a can of 134a every other year to keep it that way. Small price to
pay.
The heat index is supposed to be 105 F here today. I'm going to drive
the 944. ;)

<snip>
The original lubricant was mineral oil; PAG is normally used with
R134a.

yep, sorry my mistake.
To be honest I didnt expect it to work so anything was a bonus.
Its been 36 deg C here in Liverpool today, (I'm sure thats up round the 100
deg F mark) and the 944 was cooling better than my E36 M3 that has been
re-gassed at the same time.

I realised that I should have replaced the receiver/drier but as I didnt
know it was going to work, I thought I'd better test it first. I may change
it next time it needs a re-gas (assuming Bill Nobles prediction above is
correct).

Howie wrote:

Congratulations on having cold air!  It will be in the 90s (Fahrenheit)
here today and very humid.

<snip>

The original lubricant was mineral oil; PAG is normally used with
R134a.  The ester is compatible with both and will mix well with any
remaining mineral oil in the system.
Your mechanic should have changed the receiver/drier (roughly $25 US)
for one that is compatible with R134a ("XH7" or "XH9" dessicant).  The
XH5 dessicant may otherwise break down and get loose in the system.

Which experts were you asking?  ;-)

Actually, there are a couple ways of retrofitting to R134a.  Your
mechanic did the least expensive route, and for your climate that
probably will work fine for you.  In the US, some of the retrofits
include replacing the compressor with a larger unit designed for R134a,
which adds about $500 US to the equation (roughly £1,000?) but some
folks in the southwest US (Arizona, Nevada, etc.) and 105 degree F
ambient temps find that R134a doesn't cool enough without the larger
compressor.