1969 buick skylark a/c does not blow cold

hello gys
i have a 1969 buick skylark that has ot ran since 1988. i rebuilt the engine and trans . the a/c has pressure and the compressor turns when i turn on the air but it never gets cold.
does freon go bad or does it need to be drained and recharged or is something else bad like my orifice tube or any other thing plugged.
with woodward dream cruise here this week it would be nice to cruise in a/c.
what your thoughts on converting to 134a instead of r12.
thank you

 

Do you have AC gages? You need to get some readings in order to determine the problem.

 

I agree with the previous reply, and no freon does not go bad.