Overheating Question

[boywonder]

I'm no mechanic but...

Are you sure it wasn't 240º? My car isn't warm until over 160º. And no, not having a thermostat shouldn't cause you to overheat. If anything not having a tstat would make it harder for you to get heat during the colder seasons.

Check the wiring to your dash light.

[JeffYoung]

240 is borderline but you should be ok. If you hurt anything it would probably be the head gasket. Do a compression check and see what you get and go from there.

The lack of the t-stat COULD cause a problem, but I doubt it. Some cooling systems need the restriction the t-stat provides. Wtihout it, the coolant actually flows through the radiator too fast and does not have time to cool. Not sure if that is the case with a Miata cooling system -- go ask on the SM board. THey probably have the answer off hand.

[xr4racer]

I do not know about Miatas, but the lack of a thermostat in most racecars forces too much water too fast through the radiator not allowing it to cool. Most racecars have a thermostat or at least a flow restrictor.

matt

[xr4racer]

Since Jeff beat me to the punch, make sure you do not have an air pocket in the system.

matt

[rhygin]

Jim... guage sensors seem to be a maint item in my mind. So... get it pretty hearted up and flowing in the drive way (garage if you are lucky) and pull the cap and stick a temp sensor into the water moving passed. I have used a turkey thermometer and a temp sensor from a multimeter... try it... see what happends and let me know. i am betting on a bubble in the system even though you think there is no way that can be the case. Was with me....

at 240... bad stuff is or is about to happen... that is a lot of heat for a miata in my experience.
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