I just bought an 86 rx7, NA, and on the way home the car was reading 1/2 on the engine temp, then at stop signs and such it would go up to 3/4 or higher, then it would suddenly drop. So...i replaced the thermostat and flushed the system, horribly dirty and rusty every time. Anyhow, after all that I drove it around and it would go up really fast in temp, i drove it for maybe 3min and the temp was at 3/4, also I drove it and it was around 1/2 and then shot up suddenly all the way to the top. Now, I got out and felt the upper radiator hose and it was not up to normal temp, i compared it to a buddies rx7 and his was alot hotter. Soo Im supposing that the temp guage is just whack. but i should mention that I am just running straight water and it was letting out alot of steam into the overflow container, enought to make the top come off. Any tips on what to replace for the temp guage bein like that, or is it not the temp guage?

 

Sell it now...!

 

seriously?
I just bought it for 650 and the body is totally straight and the paint is great, i bought it with plans to rebuild the engine too, but would like to drive it a bit before i rebuild, is it really that bad? i think it s just a sensor goin beserk just cuz of how it responds to different stuff

 

No, I was messing with ya...Your problem is that you havent gotten all of the air out of the system. Adding water to the FCs isnt as easy as you may think, and if your upper hose isnt getting warm, then the water isnt moving through the motor. YOu have to add water, a little at a time, let it run a while, then add more...It takes an hour or so. You may want to consider replacing the thermostat too. Dont overheat it anymore, or its gonna be a shot motor..

Rat

 

okay, i'll try getting all the air out, but I have just replaced the thermostat, i guess you didnt see that in my post. I have a question about that tho, when I have replaced them before on Subaru's I have had to line up a little ball on the thermostat in order for it to work correctly, on the RX7, the one in there had the ball, but the one i replaced it with did not have it. so i just put it in, is this wrong? I bought it from Pep Boys, not Mazda.
thanks,
Luke