nzm10@amdahl.UUCP (Neal Macklin) (10/23/85)
My car recently blew a freon hose and lost quite a bit of A/C oil and
all its freon. The service manual says to use a vacuum pump to evacuate
the lines (to eliminate any possible water) before recharging. They give
specific instructions on how much oil to add if the system is empty.
The problem is that I don't have access to the vacuum pump and I don't
know if the system is totally empty of oil.
A friend says I can get a patch kit and replace the bad section of hose
(the hose has just a tiny hole in it) and then I can just buy some cans
of freon/oil mix. In other words, he says since this "pinhole" is not an
open gash in the hose (plus I have it taped up now) no water vapor is
in the system, so I don't have to evacuate it.
My question is: assuming I do this, how do I know if I am adding enough
oil? A new compressor will certainly cost more than taking the whole
thing in for a professional fix (though I got two $200 estimates just for
fixing the hose). Would people recommend I don't attempt this at all?
Any advice would be appreciated.
--
Neal Macklin
(408) 737-5214
...{hplabs,ihnp4}!amdahl!nzm10
[There are no opinions expressed in this article].saf@bonnie.UUCP (Steve Falco) (10/24/85)
> My car recently blew a freon hose and lost quite a bit of A/C oil and > all its freon. The service manual says to use a vacuum pump to evacuate > the lines (to eliminate any possible water) before recharging. > > My question is: assuming I do this, how do I know if I am adding enough > oil? I don't know how much oil you lost. Why do you say it is a lot? What you did lose would spray around a lot and look very messy but the amount could be small. In the GM shop manual, they tell how many ounces to add when replacing each component of the system. They also talk about draining and measuring the oil in each component to know how much to put back. This would of course be major. But I can't believe a pin-hole leak would cause much oil loss (just an opinion). As to the evacuation, intuitively it would seem that more than water vapor is being removed here. There is also air (a poor refrigerant) to remove. Low side pressure is in the 20 psi range so having air in the system would have to dilute the freon - this doesn't sound efficient. (Again an opinion.) You may be able to repair the leak yourself by changing the hose (using NEW O-rings) then letting a shop purge and recharge the system. I can't believe a hose patch is a good choice if you intend to keep the car for any length of time. Steve Falco