Automotive Air Conditioning Information Forum (Archives)

parollback on Tue October 04, 2011 5:53 PM

Year: 1994
Make: Saturn
Model: SL2
Engine Size: 1.9 DOHC
Refrigerant Type: 134a
Ambient Temp: 70
Country of Origin: United States

The car came to me with no refrigerant. So, I charged it up and it held for about a week. No obvious signs of leaks (oil). So, I took it apart and replaced the evaporator, expansion valve, drier, and the condenser. All new o-rings (with nylog), PAG 100 with dye. Vacuumed for 30 min, let it sit for 2 hours with 29" of vacuum and no change. Charged to factory specs. Cooled perfect!! about 30 psi low and 225 high. 40 degrees out the vents. Now, a week later, won't cool, compressor won't come on and pressures are 25 low and 25 high!!!! And no signs of leaks (oil or dye). What am I missing? Only think I can think is the hoses are leaking the refrigerant and not the oil or dye. Any help is appreciated!!!!

Cussboy on Wed October 05, 2011 12:51 AM

Did you also replace the compressor?

Anyway, you did a shotgun type of repair, likely replaced some stuff that was fine. I think you should've let a pro find the leak first, then you fix it.

parollback on Wed October 05, 2011 10:30 AM

I did not replace the compressor. I didn't see any evidence of leaks there (and it still works). I changed the evap because to inspect it, I had to take the whole dash apart. So, that part is new now. The condenser was beat up and slightly twisted, so I didn't want to assume that it didn't have a slow leak. The drier was changed automatically (as I always do when I open a system). That was my logic in doing this repair.

DaveMcKenz on Thu October 06, 2011 9:02 PM

You probably already checked this, but my compressor shaft seal showed up as a UV dye haze on the inside of the hood pad, only visible in the dark with UV light. The leaking oil gets blown and sprayed away and leaves only a faint residue. Also a shaft seal leak is probably a decent bet, given what you have already replaced.
Good luck,
Dave

Edited: Thu October 06, 2011 at 9:03 PM by DaveMcKenz

TRB on Fri October 07, 2011 12:13 AM

Reclaim the refrigerant and see how much you have lost. If zero was lost. Which won't make sense as you static pressure should be higher on a full charge, check the compressor for suction.

-------------------------

Dougflas on Fri October 07, 2011 1:00 PM

Make sure there is refrigerant in the system. Then, remove the vee belt, place a shower cap or plastic bag around the front of the compressor. Let it sit overnight. The next day insert the sniffer probe in the shower cap/plastice bag. If the seal is a leaker, it'll show up. Sometimes dye does not leak out of seals and that could mislead you.

parollback on Sun October 09, 2011 10:34 PM

FOUND IT!!!! I tried the shower cap trick (using a big freezer bag) and covered the whole compressor and lines leading up to it. Sure enough (using a friends sniffer), found refrigerant. Turns out it was the high pressure port where it mounts to the line. I got a new line and installed it and so far no leak. It's charged up again, so hopefully that was it. Thanks again for all your help. That darn shower cap trick is so simple, yet found the problem!!!!! Thanks again!!!!