Since last night i've done nothing but give the search function a thorough pounding. Read so many overheating posts from everywhere as well as Aaron Cake's overheating troubleshooter, so far i'm yet to find anything that describes my problem apart from the fact that it's just starting to get fairly hot here.


Yesterday as I was driving home from uni, not in a very spirited manner, just a regular drive, I suddenly noticed a wisp of steam from under my bonnet. I don't look at my temp gauge too often because before yesterday i've never really seen it move too far from the 1/4 mark EVER. But sure enough, it was pretty much as high as it goes.

Popped the bonnet, it's thrown the lid off the overflow tank, throwing steam out of there like crazy, just steam everywhere and there was a slight hissing from down around the radiator somewhere.
I belled the racq (roadside assistance) to come out because I thought it might have just been a busted hose or something. They came out and threw almost 4.5 litres of water into the rad (FAR TOO SOON FOR MY LIKING! WAS STILL FAIRLY HOT. ABOUT 45 MINUTES AFTER OVERHEAT). I waited a while longer then turned it over. It started fine but the guys suggested I take advantage of the free tow anyways because I was fairly close to home.
It was night time by this point so further diagnosis was very difficult. Thanked them for the tow and then spent many many many hours reading 'my car overheated' type posts in here.

I don't THINK the overflow tank smells of exhaust at all.
This morning I left the radiator and overflow caps off and let it run for a goodly amount of time, there was about 3 TINY bubbles in this time, very very very small bubbles. Other than that the level did not budge at all.
Took it for a short drive and everything seems fine so far, normal running temp. But we will see.

Now; what in gods name could have caused this phantom overheat for no good reason. It was not too hot at all yesterday compared to the previous few days.
For the life of me I cannot see any leaks! Not before the drive, and i parked up afterwards and just watched under the car, not a drip from anywhere.

The closest thing I have read might indicate that a new radiator cap is in order. Whatever it is, i'm hoping it isn't a coolant seal.

Thanks for reading, I know this post was disproportionately long for the size of the problem.

 

Rreplace the thermostat while you are it too, and of course, use Mazda OEM only!

 

Dude...

And I SECOND THAT STATEMENT!

USE THE MAZDA OEMS ONLY!!! That alone has solved MANY overheating problems for my cars.

Jarrett

 

Cheers guys.
I'm going to drive to work tomorrow in it, which is about a 20 minute journey. I'll carry a heap of water but see how I go. Try and get a new thermostat on the weekend.

 

I suggest that you take the car to a radiator shop to presure check your coolent system. I had a supra that leaks only when is warm enough but i never had a over heat problem, well thats untill the hole in the hose got too big and start dumping water everywhere. All i have to say is that if you have a leak is not goign to get any better and it will get worst way faster than you think. I hope you coolent seals is alright!!

 

Yeah, me too. I really can't afford that at the moment!
I'd be without a car for quite some time.