I have a 91 and was out last night with the top up and the A/C on and it felt like it could use some freon. It gets colder when driving and warms a little while sitting at the light.
Is there anyway to tell if this is the original system or has one of the previous 7 owners replaced something. The label on the compressor is there but the writing is all worn off. No label on the drier either. There is just that blue cap on the drier. Is that indicating by color the type of freon?

 

Take the cap off and post up a good clear close-up photo of the service valve.

Looks to me like it has a R-134a adapter on it but it's hard to be sure.

I'd recommend getting rid of that "breather" on the valve cover and hooking the PCV back up right, it'll help keep the oil cleaner, and eliminate the "old car" oil/gasoline/exhaust smell coming from the engine.

 

Here are the pics. I think you are right as always Sofa. It looks like the quick release fitting on the R-134 hose I have.
Man I like my little K&N breather! I do have my original parts and I did put my original VC's back on so maybe I will hook it back up.

 

Yup, that's definitely a 134a adapter... it's been "converted". To what extent, or how diligently, is anybody's guess.

Ideally, they would have replaced the compressor, rubber/plastic lines, all O-rings, accumulator/dryer, and orifice tube. Who knows whether they did all of that.

In any case, try adding a can of cold juice, and see if it gets better.

 

All soft lines should have been replaced with barrier style hoses, since the original A/C hoses were not.

 

Indeed... but who knows. I can't tell you how many I've seen where somebody just put the adapter on the port and started adding whatever, without ANY proper preparation at all. It usually doesn't end well.

 

Is any new hose going to be barrier style? How can you tell? Going to be refreshing my AC system soon and want to make sure I get the proper parts. Vinny, that is an aftermarket Delco compressor, not the original.

 

You can just look inside the hose. If it seems to be lined with a layer of hard plastic, it's the barrier type.

 

Thanks guys for the info. I did add about 3/4 of a can and all seems well and cool. When I took off the service cap I heard a slight pssst so I think the Schroeder valve might be leaking slightly, but I did notice a rubber seal in the cap so maybe this is normal. I don't use the A/C much and have not had a problem with it so for this purpose I will assume (we all know what this means) that whoever did the conversion did an adequate job.