Thanks for the post John.

Does the compressor hold its tank pressure after it shuts off? If not then you have a defective Check Valve in the tank.
I would perform this Check Valve test (below) to rule this out, you will see instructions a well as a video:

www.mastertoolrepair.com/how-to-test-check-valve-p-22524.html

- If not the Check Valve then you could have a circuit overload, so try running it on its own circuit.

- Are you running it on an extension cord? If so, plug directly into wall outlet and eliminate the extension cord.

- Your motor could be pulling too many amps. Use an amp probe or take the motor in to a repair shop for diagnosis (a last resort).

- Your Pressure Switch is defective. I would take the black plastic cover off of the on/off pressure switch and take a look at the copper contacts inside; are they burnt or varnished? If it's just varnish you can take some emery cloth and clean up the contacts, if they're fried then a new pressure switch will have to be installed.

Hopefully this gives you a good starting point!

- MTR