Sorry if this has been asked before... I searched but couldn't find anything specific. I just bought my 12a rx7 a few months ago and have been driving it around a bit. I always try to keep my eye on the temp gauge because I have been told overheating these engines causes major problems. Anyway... I have mostly driven the car in colder weather so far, 50 - 60 degrees F, and the temp gauge usually only rises about a 1/4 of the way up. Driving it yesterday in 70 - 80 degree F weather, the temp rose to just barely under halfway. I'm assuming it is just the warmer weather that caused the gauge to rise, but don't want to find out there is an issue when the weather finally gets to summer temps. Where should the normal operating temperature be on the gauge for a stock rx7? Where on the gauge does it need to get in order for me to start being a little worried?

 

Everyone says half way is as high as it should go. Personally I like it to be right above the second line. But, if it's not over half way, don't sweat it.
If you are worried, go buy some water wetter and forget about it. You'll be fine.
BTW, assuming this is your first Rex.. Welcome to the club. Nice to meet ya'.

 

just before the halfway mark on the gauge is perfectly normal and exactly where you want it to be.

here's where mine sits. oem everything:

 

You are correct, this is my first rx7. I am loving the car, just want to make sure everything is good on it. Thanks a lot for the info guys!

 

Is this the product you were referring to?

http://www.redlineoil.com/product.aspx?pid=117&pcid=10

I haven't drained and flushed the antifreeze system yet, and it's on my list of to-do's. Could I drain, flush it, and fill it with that? How much antifreeze does this system take?

 

According to the Mazda owner's manual, The normal operating range is anywhere between the two heavy hashmarks. Individual people's readings vary because these gauges are not what you would call accurate. Most will tell you that it takes a pretty hot day to get marginally above halfway, & generally things should run below there if you have good airflow.

Start to worry if you begin to approach the upper hashmark - - even in stop and go weather on 100 degree days you should not get up that high unless you have an issue.

Don't operate at or above that level if you can possibly help it, as you start risking the warping or damage of expensive parts.

 

What I would do is: drain antifreeze.
Refill, and start with a bottle redline water wetter(or equivilant) Fill the rest of the way with good 50/50 antifreeze.

This is exactly what I did except I used some WixCool cooling treatment.
Comes in a regular ol' wix bottle.
Water wetter is also good.
Royal Purple Purple Ice is best that I've tried.
Mazdatrix sells some neo cooling treatment I'd like to try, I bet it's good.