i was running w/o a thermostat for a week and it stayed at about the 1/4 mark. i just installed a new mazda oem tstat saturday and now its running at about the 3/4 mark....how bad is that to drive with and what could be causing it to still run so hot? its a stock 88 n/a engine...i also had the fan replaced b/c that wasn't working so well, but i'm not sure why its still running hot now...

 

dumb question but did you put it in upside down?

 

If you have an 88, and its at 3/4, then thats a very bad thing. Thats getting into dead engine territory. 1/4 of the way up is normal operating temperature on 86-88's. Also, when does it overheat? When stopped, when driving, or all the time?
http://www.aaroncake.net/RX-7/cooling.htm
http://www.aaroncake.net/RX-7/overheat.htm

 

maybe air in system? try bleeding it..

 

wow, running at 3/4.. you're going to kill it.

 

yea i figured 3/4 wasn't good... and it does it all the time. yes the thermostat is in the right way, and theres no air in it at all. i have no idea why its running hot now when it was fine without the tstat, especially when everything seems to have been done right. does anyone on here live near lowell, ma that might be able to help me out?

 

i believe that there are different temp ranges. there's cold, hot, and normal. this is what i've heard not saying its true, but its possible you got a hot one

 

3/4 is perfectly okay if you don't really care about your car or if you drive it minimally. You can actually drive normally for several months or more at 3/4, provided that you pull over the moment it hits 7/8. I had a different RX-7 before, that's how I know. Lost it to an accident not to heat problems.

The FAQ is a great place to start for running hot. After that:

1. I assume you replaced the fan clutch or bought an e-fan?
2. Check for coolant leaks. Search for more info.
3. The volcano test for bad coolant seals. Search for more info.
4. Have cooling system tested. Pep Boys will do it for $30, but service is poor. You'll have to leave your car all day. They'll mostly locate clogs by finding rapid temperature changes. You could probably do it yourself with one of those thermometer gun thingies, or a thermometer and some patience.
5. Check radiator, water pump, etc... ask somebody else.

 

Im gonna thread steal real quick, not worth making a new topic. My stock 87' TII runs at about 1/4-1/3 gauge all the time. Is that normal? I figured at least 1/2 gauge, since its a turbo car and all. If not normal what in the hell is making it run so cool? Any other car and Id be thrilled about it running cool

 

Well, if the gauge is the same as the N/A guage then that's normal, or perhaps slightly warm. Thermostat triggers between 1/8 and 1/4. 7/8 is overheat.