I tried charging my A/C system today, I put in 12ozs. of R-12 first,
compressor started kicking on, & off at the end of the first can.
I shot in about another 6ozs. no change, kicks on and off.
My gauge only showed about 25lbs on the low side, The hi side I couldnt
test wrong fittings.
Are there any other tests I could try with any of the
cut-offs. I don't have a good manual for truck.
Its an 86 w' 350
Thanks for the help guys.

 

I stopped by an A/C shop today, I talked to the owner and he said
these older systems take about 3 lbs of refrigerant. He said he
will leak test it for me and give me a good deal on a recharge.
He also told me that the 4cyl. reciprocating compressors usually
develop a compressor seal leak. I will drop it off Monday, I don't
care, I need air. I'll post the outcome.