No Takers on my A/C problem?

I have a 1994 F-250 PU, 4wd, 5.8L, approx. 175K mi.
Recently my A/C started constantly cycling on and off, and blowing hot air. The compressor on for a second or two, then off, on for a second or two, then off. I put a set of gauges on the system, did a static check, saw approx. 65 psi on both the low and high sides. I then bypassed the clutch cycling switch and got the compressor engaged and running, but saw no change in the pressure readings on either side of the system; steady reading at 65 psi. Is the compressor bad? Any ideas? Someone help me before I spend a ton of money! Thank you very much for any help.