Myster

Ok, i have a major delima...

First off, i come home from a party one morning, and i get in my car. And i notice my switch to turn on my engine fans isnt working. So im like hmm...I then drove the car to one of my friends car shops. I had the radio off on the way there, and was driving extremely slow and listening to any abnormal sound coming from my engine ( which it did not make). But the bad thing was that my temp gauge got up to around 240F for a very brief period of time!!

I turned the car off when i got there and popped the hood. The engine was pretty damn hot, but it sounded perfect at idle and the whole way there. After letting the car sit for about 15min, i noticed it started leaking out coolant. I was then told that it is normal for the car to do that after it gets that hot. So i calm down a bit.

I come back later that day when they fix my fan switch and i start the car up to leave, and i notice after like 2min of idleing the car started to get hot FAST. Like 210-250F in a matter of 2 minutes just sitting there. So, we turn the car off, and let the fans stay on and pop the hood. The engine wasnt hot at all (????) but the thermostat housing was pretty damn hot. Also the radiator wasnt hot. So this lead us to believe that the thermostat was stuck in the 'closed' position. So, they ordered my new thermostat and today they installed it. I call around 1pm to check on the car and they said that it didnt fix the problem!!

So...the shop has been trying to reach Peter Ferrall with no luck so far. And everyone at the shop is leaning towards thinking that the engine is cooked. But i dont think the engine is fried! There is nothing leaking, no white smoke coming from the exaust, no nothing. It sounds perfect at idle. But the damn thermostat housing just gets hot, like 240F in a matter of 4min idling.

Maybe there is something @#%$ up in the radiator?? I just REALLY hope it is not a blown engine.

If you have read this far i thank you and would like any information you are willing to give me. Someone already told me to tell the people at the shop to drain the coolant and get out all of the air in the radiator. So, thats my next job.

Thanks

karken29

First of all the 3rd gen take approximately 8.8 liters of liquid in the cooling system as memory serves. Make damn sure you running about 80% or that as water and the other 20% as anti-freeze... To often folks will mistakenly assume that "...if a little anti-freeze is good... than more than is OEM recommended is better! WRONG.... So, that's the first thing to check..

The next thing to take a close look at is you radiator pressure cap... Make sure its "non-vented" and rated at 13psi. The cap I'm referring to is the one that goes on your AST (air separation tank). This is part of your closed system. If that cap is bad you'll overheat.

You don't say how you're getting your temperature reported i.e. After-market Temp Guage, ? Power FC readings on a hand-held etc...

While your fans were off-line, did you drive the car very far? You don't really give enough detail here. regarding time and etc.

What is the condition of your cooling system ? Do you have a stock radiator? Are you routinely changing out your coolant? What is/was the condition of the fluid that did leak out? Did you measure how much coolant/water your put back in the system when topping off?

How bout your hoses? Are they in good shape? Any possible leaks there?

Myster

I got my temperature reported from my After-market Temp Guage.

I have a stock radiator and i've only had the car for two months so i have not refilled any of the fluids yet. The fluid that leaked out looked straight like anti-freeze, nothing visibly wrong with it. The shop did not put coolant/water back in the system afterwards, they said it looked full afterwards. Maybe we just need to flush it and add 20% anti freeze and 80% distilled water?

All of my hoses seem to be in good shape.

I drove the car for about 10minutes with the fans off-line. The car did not over heat while driving , only simply when i was stopped at a stop light/sign. But it was only at 240ish temp wise for a very BRIEF period of time, like right before i got to the shop ( was in downtown, very stop and go traffic).

Thank you for the insite.

karken29

The easiest thing to do is drain the coolant system and replace it with the correct ration of water/anti-freeze.

Water has a cooling index of "1". Anything added to it lowers its index rating and so diminishes its ability to remove/absorb heat from the engine. Think of it as a glass of water, into which you begin to add stones. The more stones you add, the less water you can have in that vessel.

Also, try replacing your cap on the AST tank.

These 2 items are low cost things with BIG impacts on coolant system performance. Let me know how you make out.

BTW... Once you have your coolant system refilled, don't get wrapped around the axel about "Burping the system.... Once you refilled the system from the fill-neck on the engine, do any subsequent "Water" additions form the AST Tank. This check should be done when the engine is completely cool.

good luck,

Rich

rx7superman

From your discription it sounds like your thermostat is bad. I would check that before thinking the engine is bad. Even if your seals were going your motor would'nt get that hot that fast unless it were really bad. Thats just my 2 cents. Goodluck!

Myster

i already changed out the thermostat.

ianlee

I dont know if you'll get this post, but here goes.

I had the same problem on my 91 chevy S10. I kbnow their both different vehicles, but the cooling system on all cars are pretty much the same. The temp would raise shy high sometimes, and then fall a little while driving and then rise high again as if it had a mind of its own. But the engine would run and sound just fine.

we thought it was therm. problem too, but it was actually the water pump. Changed the water pump and all the problems went away. Try looking at your water pump.