a/c compressor

I have a 71 skylark 350 2 barrel just bought recently today I was able to get the a/c compressor to kick in but nothing gets cold no cold air out of any vents

 

The blower motor is on the firewall behind the passenger fender. Is it turning ?

 

is any air coming out of the vents?

 

yes blower is turning putting out air but its just hot and none of the a/c lines are getting cold

 

Is the system charged? you know if it has been converted?

 

no I think its still r12 but it must have some Freon in it to turn compressor on right

 

No air from vents or hot air?

You are low or out of freon. Mostly likley there is a leak in the system.

The question now is do you also have an issue with the air doors based on a leak in the vacuum lines etc?.

 

it will change from heater to defrost to vent to a/c and blows warm air out of each one I just thought when a compressor kicks in it means there is Freon in the system or it would not kick on

 

Not necessarily. If the system is not equipped with a superheat switch (and I don't think your system has one), the compressor will run even with the system empty. Look into the sight glass on the receiver-dryer, which is next to the radiator on the passenger's side. It should have a little black plastic cap covering the window. If it has foam, it's low. If it has streaks, it has no refrigerant, it is circulating oil. Most current systems have a CCOT- Cycling Clutch Orifice Tube- setup, which will cause the compressor to cycle, or not even engage, if the system is low enough on refrigerant. That may be why you expect the result you are not getting.

 

ok thanks I will check it tomorrow

 

looked in the glass theres nothing so must be out of freon

 

There is a "reasonable" cost substitute for R-12, if you have the equipment you can charge it yourself. Since you may not know long it has been since it was charged last, maybe just put one can or part of a can in that has the leak detector in it and look for leaks. The system probably doesn't have air or moisture in it yet, if it didn't sit open. So, after the possible leak is fixed, you could put on another receiver/dryer and evacuate and recharge the system. Depending on where you live, you may not need to use the full potential of the A/C, and you could charge it with TC-134A instead of R-12, since it is so much cheaper and available. That means you would have to flush the compressor oil that has migrated through the system over the years, change the oil in the compressor and replace the o-rings to a type compatible with the new refrigerant. It's wise to replace the seals and Schraeder valves anyway, given the age of the system.

 

ok thanks