Either your brakes are sticking or they are adjusted to much.
it was the e brake line was to tiet Shoes are touching the drum adjust back until freely rotating.
heater core hoses not hot
The variable resistor has probably gone bad
Could be a faulty temp sending unit.
fuel pump connector hot wire
Car Engine Overheating - Troubleshooting Check related link below…
a couple of answers would be right one is the blower motor or another would be the switch
over use of brakes, or parking brake set while driving, or possibly dragging brakes on both sides (not likely). Check the parking brake!
The sensor can be checked for resistance with an ohm meter. The sensor can be checked while cold then hot for resistance change.
One or both shoes are stuck out. Emergency brake is on just a little bit or it needs adjustment. It may not be the brakes but the wheel bearing going bad and heating up and the heat transferring to the drum.
Brakes are adjusted too tight. Brakes are misassembled. Brake hose is restricted, holdings the brake on.
remove the boot, and tighten the adjuster nut. just don't over tighten it. your brakes will drag an overheat the drum :P