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Replacement parts for General Electric DBXR463ED2WW Electric dryer | AppliancePartsPros.com

I doubt it is a limit switch.

Sounds more like the motor is overheating. It's internal thermal protect then opens and the unit shuts off. It then cannot be restarted till the motor cools down and the thermal protect resets.

If it starts up on it's own then I think you have a centrifugal switch problem.

One of the centrifugal switches on the motor is for the windings.
The other is for the heating element to ensure it does not come on till there is air flow.

The motor switch does 2 things.
1. It disconnects the start winding once the motor gets close to operating speed. If the start winding is left in circuit the motor will overheat.
2. It provides an parallel circuit path for the start switch so that you can release the start switch and the motor will continue running.

If the unit starts up all by itself after overheating my guess would be that the switch is always being held closed. This may just be a dirty clogged up centrifugal mechanism on the motor or the switch is shot.

I am assuming that you have to push the start switch to get the unit running initially.

How long does it take for the unit to shut down.

Had one not long ago where a seal at the blower was shot.
This was then blowing hot air on the motor making it overheat.
It would take 5 to 10 minutes.

This might also cause the unit to run hot as the main control thermostat is on the blower assembly.