[Supras] A/C sealers

[berniek at technicaldevelop.com]

Chad Fernandez had asked why retail auto parts cartridge type sealers 
should not be used.  I have a '91 now which had perfect A/C until the 
compressor suction hose got punctured during an engine change this past 
summer.  Had a '90 before that which had a slow leak, which could not be 
found using a freon leak detector.  Yeah, in retrospect I could have 
checked the evaporator chamber drain hose, but made the assumption that 
since the compressor shaft seal was OK and there were no visible oil 
leaks that all was OK except probably the evaporator.


I scoured A/C supply websites after having bought a sealer cartridge 
from Advance (under their old name, which I forget) to make sure the 
stuff was OK.  There were links to articles written by A/C professionals 
indicating that the mechanism by which the cheapo sealers work clogs 
compressor reed valves and expansion valve orifices.  The stuff I 
finally bought was made for pros, and worked as stated, using moisture 
outside the leak area as a catalyst for hardening.  It's been at least 
10 years since this happened but it worked fine. 


One more item:  The compressor started to seize because of oil loss due 
to the leak (never found oil under the car where the evaporator vent 
was).  $450 later I had a new Advance compressor and receiver dryer 
(also have about 60 pounds of R-12).  Took the old compressor apart and 
found that the swash plate shoes just began to score the aluminum swash 
surface.  The filter dryer had no particles other than micron size stuff 
visible under a microscope in addition to larger pieces of aluminum 
chips from manufacturing.  All of that stuff was on the outside of the 
filter. 


The upshot is:  I could have added oil through the compressor suction 
port and been back in business.  If you do this make up a dipstick from 
1/16" wire and wiggle it down past the swash plate and pistons to the 
bottom inside of the compressor through the suction port.  Oil depth 
should be about 1" to 1.5".  Could have saved $450.


BernieK