Okay so I finally got my gauges and found the 90 fitting I needed to connect to the high side (pic below) on Amazon round 12 bucks. I had a buddy helping me charge the system and I didn't get a look at the pressures before we started adding 134 through the gauge set. But after one 11oz can my Low was around 30psi and High 250psi. These numbers seem to be good based on the CSM performance chart and only charging to 80% being 134 in an original r12 system. The compressor stayed on and stopped cycling on and off, the AC was cold blowing around 48 degrees. But when I accelerate with the compressor on it makes a screeching noise, it doesn't look like the belt which is new and I cant tell if its the clutch slipping making noise. The bottom of the belt does wiggle a good amount with the compressor on (the belt area between the crank pulley and comp) not sure if that's normal. Any idea what the noise can be and is there a way to tell if the clutch is bad? Thanks.

 

Glad you were able to charge the system, however, no way to determine how much R134 is in your system, IMO, based on the gauges, I think the system is low on R134. Hard to know about the compressor noise, maybe the clutch, which is a bear to replace, most guys replace the compressor at that stage.

 

I have the same issue (screeching noise when I accelerate with the AC on). My AC belt has roughly 1" of play. I'm not sure whether it's the belt or the compressor. Anyone know how to rule out the AC compressor. The noise is intermittent and stops immediately when I switch the control to off. I live in Philly. Rough city. The noise is so loud you can't hear the bullets!!!
I remember there was a member on our site who rebuilds the original AC compressors, but I can't remember the name.