Hey folks on my way uphill the upper radiator hose slipped off. and the Temp went up to 3/4. I quicky shut down the car. On the highway and let it sit for about 20mins walked to the gas station to see if they sold 50/50 coolant and barrow a screw driver. I let the car cool for about another 30mins. Opened the top and slapped in some coolant just about filled up the radiator. now that everything is hopefully coo. Is it still safe to drive the car without harming the motor? Also I drove the car home. Rolled it down hill. the Rpms stayed about in the 2k rpm range. The temp gauge reads from cold to 1/4 as I had to turn the car and drive about 2 miles. So whats wrong with the temp gauge? Also there is no milky or brown looking stuff in the oil. However the coolant has some gray stuff ( looks like the RTV sealant I lightly used) for the waterpump and thermostat. I hope I didn't blow the motor.
thanks

 

Due to the structuring of your post I am not sure what you are asking or what really happened. You may want to explain in clearer detail.

I can tell you that I've overheated my NA S4 many times and ran it pretty dry on oil many times.... Yet the car still runs like a champ and starts up fine every time. Apparently turbos are the finicky ones.

 

It got hot but did not overheat and the temp gauge only goes up 1/4 like a S4. Any ideas why the gauge only goes up to 1/4? Thermo sensor behind the waterpump?

 

The thermostatic sensor for the gauge is on the rear iron, under the oil pressure sender (or at least on S4s it is). But I don't think there would be anything wrong with it. If you only drove it for 2 miles, the car probably just never got back up to full operating temp.

Drive the car and then draw some conclusions. At the worst, you could have blown a coolant seal, which would cause it to overheat / boil the coolant. These are things that should become obvious with a little more driving.

 

I did some hard drving and it burn gas quick and this was after a 15min drive and a jack rabbit start. Im begining to think my thermostat is stuck since fuel economy has suffered.

 

Bad thermostat symptoms come up really fast and hit really hard. And my fuel economy was perfectly fine with a bad thermostat...

 

Do you think the gauge just could of went out? It seems to take more time to get out from below C to 1/4 of the gauge.

 

Both cars listed in your sig are S5, so the temp gauge should be reading 1/2, not 1/4.

Not that the S5 gauge is much more than an idiot light with pretensions, but still.

I'd guess you still have air in the system.

 

^ Along that line of thought, air can cause wrong readings at the sender for the gauge and prevent the thermostat from opening. Run the car with the cap off until warm, heater on hot, until no air bubbles are seen.

Same applies to coolant changes.

 

pfsantos. I think that maybe it. thanks for the help everyone.

 

Hey thanks for the advice earlier pfsantos.
I did that for about 15 mins. and I didn't see any air bubbles. I think that that thermostat is stuck open. It takes forever for the car to warm-up.
Im checkin the Haynes manual right now. And it says On p 100 sect. 3 Thermostat and I quote " If the engine seems to be taking a long time to warm up( based on the heater output or temperature gague operation), the thermostat is proably stuck open. Replace it with a new one.' here we go again.
Do you think thats the problem ?

 

Take it out and see if it's open. Same exact Haynes manual shows how to test the thermostat. I did it with the old, and with the new just to be sure. I have a thread how to somewhere. Search (advanced) "change replace thermostat" with my username. Not an authority on this stuff, but I once went through the same thing many moons ago and learned some stuff as a result. Good luck.

Make sure to put coolant in the hole before putting the thermostat in.

 

I just pulled the thermostat out and it was stuck open. Thank you for all the help. Hopefully thats the problem. D'oh i just got your post pfsantos. I'll guess I have to burp the system again. lol

 

Let us know how you fare. Another current thread:

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/thermostat-stant-837236/

Mentioned in post 12:

https://www.rx7club.com/showthread.p...ght=thermostat