OT - Automotive A/C question

 Drinks for anyone who is thirsty.

Low mileage 1991 Chevrolet Caprice Classic 305 V8. I had the A/C system
retrofitted for R-134 last fall and it worked fine. This Spring I find
that it doesn't work. The shop that did the retrofit confirmed that the
compressor is leaking. (Used dye in the freon.) It didn't have a
mechanical failure...just a leak. They said it would cost $800 or more
to replace it. Even though the evaporator was changed in the retrofit,
they would be required to install a new one for the warranty on the new
compressor.

I don't have $800 to spend on it.

The rest of the system is probably fine other than moisture and air in
it due to the leak. So I thought that I might just replace the
compressor myself and have a shop evacuate and charge it. The car is
old, but has only 80K miles on it. Everything else works like new...and
it gets 28 MPG on the interstate!

Whadya think? I can easily do the mechanical work, but I don't have any
AC tools or AC repair experience.

Thanks.

Andy aka Big Stinkie

 Andy aka Big Stinkie" <"andy at bigstinkie dot com wrote:

  Seal leaks are often a result of not operating the system for several
months during the winter ... ya gotta keep that oil circulating or the seals
dry out . That said , yes , by all means replace the compressor , and have a
shop evacuate and charge the system . It might surprise you to find out how
little air and moisture get into the system . I mean , it's not like you've
got both hoses open to the air ... for months . In fact , under very similar
conditions I've successfully swapped out the pump without vaccing the system
. I DON"T RECOMMEND THIS APPROACH IN MOST CASES . However , it is an option
. Either way you go , as soon as you unblot those hoses at the compressor ,
cover the ends with tape , or a plastic bag over the whole block and well
taped to the hoses .
  For that matter , you might get by this year with a can of that seal
conditioner the chains sell . Or maybe you'd prefer not to Hack(tm) the
system .
--
Snag
Learning keeps
you young !

 


it doesn't; take long to saturate a dryer with a open system, particularly one
that has not been run to burn off what condensation had accumulated in the AC
accumulator (aka dryer)  (hehehe pun intended)

 On 4/11/2011 9:18 AM, Snag wrote:

<There. I snipped some.>


The shop said that R134 is at a higher pressure, too. I had it changed
over because the old stuff had leaked out. (I drove it for 4 years and
it worked, so it musta been a slow leak.) The higher pressure may have
caused the leak to worsen. <shrug>


Kinda what I was thinking. It's been a total of 5 months since it was
changed to R134, and several of those months it worked, I'm sure. Hard
to tell when it finally leaked enough so the sensor wouldn't let the
compressor turn on. Shit...might have been the day before I tried it
again for all I know. <grin>


Got it. Good points. I'll think I'll go the more thorough route and
evacuate it. I know of some folks that have the equipment...or I might
just find some at a pawn shop...and go that way.

Andy aka Big Stinkie

 On Mon, 11 Apr 2011 09:00:59 -0500, Andy aka Big Stinkie <"andy at bigstinkie
dot com"> wrote:


evaporator or dryer, dry yes, evap only if it is leaking


they had to mean dryer


replace the dryer too, but you need to replace the dryer close the system and
hit it right then with a vac pump

look at a pawn shop for a cheap vac pump, it should still pull a vac to 29.9
or it is a POS

the air powered ones work too, but only the quality ones with enough of a
compressor pulling them


there is nothing to it, I can walk you through it over the phone

tom