[dhoward]

It's not a compressor problem.
The motor may be gummed up.
See if you find some of that air tool oil that smells like wintergreen. Good for loosening the gunk. Or shoot some break-free down the pipe and run it, followed by oil. Unscrew the adjuster all the way out and make sure that passage is clear. Sometimes a peice of machining crud gets left in when they're new...