Why doesn't my air compressor shut off?

In respect to this, why doesn't my air compressor shut off?

If the air pressure in the tank doesn't reach the normal cut out pressure level, and since then the air compressor can't shut off as the pressure never reaches the cut out pressure level, then look to the intake valve or internal gasket leak as the possible source of the problem.

Subsequently, question is, how do you adjust an air compressor cut out? Step-by-step procedure:

1. Starting from an empty tank. Start the compressor and let it run until it reaches the cut-out pressure.
2. Open a drain to slowly let some air escape. Watch how the pressure slowly comes down.
3. Wait until the compressor starts.
4. Adjust the cut-in pressure with the big set screw.
5. Close the drain valve.

why is my compressor not filling up with air?

Air Compressor: Won't build tank pressure. Shut the drain valve at the bottom of the tank if it's open. Check for air tank leaks and replace the tank if it's leaking. The valve plate regulates airflow into and out of the pump cylinder to compress air, so replace the valve plate if damaged.

Why is my compressor constantly running?

If your air compressor is constantly running without shutting off, this could be a sign of a problem—and it is probably costing you a bundle. But this simple system is problematic in that the compressor will usually overheat if the it runs more than about 50% duty cycle.