Expert: Ben Deutschman - 8/9/2009

Question
i have a 1989 ford bronco with a 302 it gets overheated when you stop and go alot it has a leak comeing out of the thermastat gasket and it dont have a thermastat

Answer
First off, it is a misconception that leaving out the Thermostat, causes a vehicle to run cooler. The function of the Thermostat, is to act like an automatic gate keeper, by opening when the Coolant temperature reaches the Thermostat's rated level, and closing when the Coolant in the Engine drops below the Thermostat's rated level. By doing this, the Thermostat does two things, one, it maintains the optimum running temperature for the Engine, and two, it allows the Coolant in the Radiator to Cool sufficiently, before going back into the Engine.

In so far as the Gasket Leak is concerned, the leak could be allowing the Coolant level to drop to a level, where there simply isn't enough Coolant in the system to dissipate the Engine heat. I'd remove the Thermostat Housing, thoroughly clean it, and the mating surface, apply a thin film of Permatex #2 Gasket Sealer to both sides of the new Gasket, the Thermostat Housing, and the mating surface, install the correct Temperature rated Thermostat for your vehicle, and reinstall the Thermostat Housing and Thermostat. Then of course add the right amount of Coolant to the Radiator, and Overflow Tank.

Most Auto Parts Stores can look up the correct temperature rated Thermostat for your vehicle.