DeWalt 4 gal compressor runs a very short time, then trips the overload switch

[oldnslo]

Here's the backstory. Purchased for $20 at a Sr community garage sale, and when I asked that it be fired up, the guy reached for the overload switch, and it fired up. Except I didnt know it was the overload switch at the time.

Fast forward to me changing the oil on it after purchasing it, and it was run occasionally at the back of the garage for very small jobs for the past year. It just doesn't get used. It used to run for a full tank fill cycle or two, and sometimes would need to have the switch reset. Now, the switch protects it after perhaps 10 seconds.

The motor is free, no apparent piston scraping sounds when operated by hand.

Where might I start to diagnose the overloading issue? The capacitor?

Unit here: https://www.homedepot.com/p/DEWALT-4-Gal-Portable-Electric-Air-Compressor-D55153/202514521#overlay

Pic of the innards below

[goodfellow]

I'd check the switch first and then the cap. If you can get at the switch, douse it up with some contact cleaner and cycle it a dozen times --

Good luck!

[oldnslo]

Cleaned the switch and tested the capacitor. Cap is in spec, the cleaning didnt impact anything. I deleted the thermal switch, relying on the thermal switch in a short power strip, and hooked up a Kill-a-Watt meter. It reads 10 amps while running, so I believe I am in spec with the consumed load.

A longer test run with the bypass is in order, then it appears I need a replacement thermal switch.

[oldnslo]

Case closed. The replacement thermal limited switch cured the ills. Its been performing flawlessly for a month.

Thanks all!

[goodfellow]

Excellent news - congrats!