There are several possible failures that could cause the pump to become hot enough to trip an over-temp switch.
Air in the suction line will cause the pump to never bring pressure up to the 50 pound cut off. It should be self priming.
A kinked suction hoses can also cause failure to raise pressure high enough.
A defective or stuck pressure switch.
Many owners switch the pump off whenever they leave their unit. There are other failures that can happen when left "on" while unattended. Flooding inside is one of them.
I wish you good luck and happy trails ahead.