Automotive Air Conditioning Information Forum (Archives)

jgcox6 on Mon July 18, 2011 12:29 PM

Year: 1983
Make: Chevy
Model: El Camino
Engine Size: 350
Refrigerant Type: R-12/134
Country of Origin: United States

I am working on a friends 1983 El Camino that has been converted at some point from R-12 to R-134 and have a couple of questions. First the car's original engine has been replaced from a 302 to 350cc engine. Other than that, all looks original. What would be the R-134 capacity for this car? What would be the oil capacity and would you put in PAG after you flushed it? Is anyone using the mineral oil on these conversions? Can you give me what the "normal" good gauge readings should be?

mhamilton on Mon July 18, 2011 3:49 PM

I converted my '80 Malibu a few years back, the same car from the firewall forward. The oil for 134 must be PAG or Ester, never mineral.

Pressures and capacity depend on how the conversion is done. You usually start with 85-90% of the OE charge and add slowly from there, checking pressures and temperatures. If you use a good condenser and a white orifice tube, you may end up at the full R12 charge level (3.5 lbs). You should really update the OE condenser, as with mine I found the high side to be excessive and idle cooling was very poor. I also plan on trying the Ford blue orifice tube, and with that I hope be able to get better pressures.

spongebob on Wed July 20, 2011 3:10 PM

go back to r-12!!