Overheating problem

[mtrx804]

Well I don't know exactly whats wrong with it gets to about 65% of the way up the temp gauge and I have replaced the thermostat sensor (because it wasn't turning the fans on) found one of the fans wasn't working so I replaced that, then did a radiator flush, and I have also made sure the water pump is working correctly any one have any ideas why it would still be getting a little warmer than it should be?


Also the temp has gotten all the way maxed out a couple times while driving on the highway.

[channelmaniac]

The Thermostat sensor isn't a sensor if you're referring to the one on top of the thermostat housing. It's a temperature controlled switch that turns on power to a relay that turns on the cooling fan. The real temperature sensor is on the back of the head.

Have you replaced the thermostat yet? That's the biggest culprit.

Don't go cheap, get the safety model thermostat. It's only a couple of bucks more.

[mtrx804]

Yea sorry I meant temperature switch, Ill try replacing the thermostat see if that works.
Thanks :)

[shortshift]

Did you have a look at the lower radiator hose? If it collapses during running it could shut off the flow of coolant.

[channelmaniac]

And if you're chasing down hoses to replace, don't forget the pesky one that goes from the driver's side fender over to the engine. That one is VERY easy to overlook and is prone to heat damage as it is in close proximity to the exhaust manifold.

[mtrx804]

Sadly I have to wait till this weekend to check it all out but thank you for the ideas Ill probably end up changing all the hoses since im checking them all anyways while im replacing my driverside fender.

[POS Racing]

How old is the radiator?

If it is the original it more than like needs replaced the Miata radiator is not a lifetime part.

[HudsonHawk]

Also check your radiator cap. If its old or damamged it can cause the system to loose preassure and overheat.

[mtrx804]

I think its the orginal one but its losing fluid pretty bad i think that the drain plug that screws in at bottem is leaking alot yea im just going to buy a new radiator.

[channelmaniac]

Save the mounting brackets for the old one if you put in an aftermarket radiator. They are needed if you ever want to put an OEM one or an aluminum aftermarket racing radiator in.

[mtrx804]

Well apprently the leak is worse than I thought from that drain plug, flushed and filled about what a 2 weeks ago and it was pretty close to being empty in there yesterday, filled it up and was perfect in temp. so where can I go and just pick up a drain plug? I called autozone and Nappa neither have one.