i dont have much experience in the broken thermostat field so i was wondering what some characteristics of a bad thermostat were.

obviously overheating is the major one.

one thing i also noticed was when i take the radiator cap off and let it warm up for a while it will start to overflow slowly out of the radiator. then itll go down and the coolant will start surging about every 3 seconds. it will go down then it will shoot up like a fountain and it will repeatedly do this until the level just gets too low and the surging coolant doesnt reach the top of the radiator.

i was thinking it might be a blown headgasket but the car doesnt smoke at all and it runs perfect other than the overheating problem. and i know it doesnt necessarily have to smoke when the headgasket is blown but its usually a common symptom.

any ideas????

 

The cooling system is under pressure, thats why it overflows, the cap keeps it from doing that.

 

...this was just my problem the other day....exact same thing was happening to me...I was pissed because i was thinking head gasket too....but changed the thermostat...and everything is fine so far...so that is probably your problem.

 

thanks for stating the obvious. dont reply to my question if u dont know the answer and just want to be a wise ass

i took out the thermostat and its fine now...weird

 

umm oooo k? You asked why it over flows, and i told you. Not everyone knows a cooling system is under pressure.

 

sorry man just seemed like a wiseass comment at the time.

i drove around for about an hour today with the a/c on and the temp gauge never moved above 1/3 of the way up. must be either the thermostat or the switch. thanks