I have 90' C2 cab and have no intention of converting to 134 as my friend has been hoarding cans of R12 for yrs so plenty in stock. Just want know the correct high and low side pressures. Trying to detirmine why my a/c compressor cycles on and off with a best temp reading at 63 out of the center vent. And yes, condensor fan runs up front..Wondering if I am low or over charged. Thanks.

 

At 80F ambient temperature

R12
High 210 - 260 PSI
Low 9-13 PSI

Center vent should blow 48-54F

 

the only way to know is by weight you can have 1 pound or 3 and have the same pressure readings. Pressure readings can help you tell if there is a problem or not, but it cannot accurately tell if the system is fully charged under or over-charged with refer.

Suck all the refer out and weigh it.

 

So I thought something around 40 low and 180-200 high? I must be waaaay off..



At 80F ambient temperature

R12
High 13- 16 PSI
Low 9-13 PSI

Center vent should blow 48-54F

 

I am a idiot. I may have read the guage wrong last time I checked..Opps..So static reading and running reading? Assuming it is 80f. I have searched everything till my eyes crossed. Can't find the info. This car keeping me quite busy recently..
Thanks.

 

whoops the lows are right per the book, the highs were off, it shows 210- 260psi

 

Thanks laker. I also was just doing a crash course on ac systems. learned a bit about ambient temps plus 100 etc..I think I have a mixing flap issue even though all servos work when you watch them move. I also think one blower fan for pass side is not working, and I read that fan on 4 should blow your hair it is so strong and mine does not. I also have heat coming from vents when climate control is off (it is 90f) everyday recently here in Boston. So it would seem I may have to do more investigation. I did get my new CCU fan today in hopes it would help things, but nope..Maybe Rocket Rob will let me come hook the car back up to the computer again! What do you say Rob! He must be reading this! Hahah

 

Greg - Yes, you can get another scan but I'm busy the next few weekends.

 

Thanks buddy.. let me know what I can do to show my appreciation. Just let me know what works for you. Also any thoughts on the clutch/flywheel?