might not be seated correctly? but there is a possibility that you need a better thermostat, not sure if the oem changed the thickness of the seal going from metal to plastic, but the aftermarket may have not. This thread is really the first time i have heard of the metal thermostat not sealing.

(and i know its op is old.)


odds for you are once it cools down which i am sure it has already, to start it and see how it runs, it would take 3-4 minutes at least to get hot.. so you can run it for a minute to see if it runs..