russ d
+1y
that doesnt mean its not bad. I have had bad thermostats right out of the box. Its an 8 dollar part with a new gasket.
If you want to check your thermostat, run the engine at idle for a while. If the top rad hose is too hot to touch and the lower hose is cool, your thermostat is plugged or the rad is.
Fix the leak. Cooling systems are made to run above the boiling point of water by pressurizing the system. The higher pressure raises the boiling point. Any leak will introduce air and allow the system to boil.
Check for an air pocket in your cooling system. Park on a steep hill, nose up, turn the heater to hot and run the engine with the rad cap off. This will force any air bubble in the system to the highest point.
Proper cooling is especially important in zero degree and below weather. At those temperatures, a working thermostat it is not so much to keep your engine from overheating, but to allow the engine to reach operation temperatures sooner. If the engine is ru nning too cool, gas mileage will suffer, and engine wear will result from the rich mix. If your temp gauge never gets to normal, or it fluctuates a lot in cold weather, put some cardboard over the front of your radiator, it will also allow the engine to warm up more effectively.
Clif Notes
Fix the leak
Check the hose temperatures
Bleed the system
Watch the gauge
replace the thermostat (if needed)