Pump stops running on high speed

You have a magnetek motor and it is overheating and cycling its thermal overload. A local electric motor repair shop may be able to fix it however it will likely need to be replaced. It is to costly to repair the motor if the damage is in the windings.

Assuming at that low a horsepower it is 115V, the likely replacement motor is a catalog #BN37. We sell it for $157. You are usually better off replacing the seal when you replace the motor and most Jacuzzi pumps are either a 200 or 1000. They should be around $5.

These are a hard motor to work on. i would suggest unplug it from the motherboard and un hook the plumbing and bring it to your local pool pump motor repair guy and have him test it. it just may need to be blown out with compressed air. do to dust in the start points