Well I was driving my car for 4 hours around town. Then when I got home and parked it it started to make a hissing sound under the hood while steam was coming out n when I looked under the car it was the antifreeze coming out thru the overflow bottle. Anyone have an idea why this happend?

 

possibly bad radiator cap, check that first. Did u notice if it was ever getting hot when u were driving it around?

 

Yea got hot but I didn't think nothing of it cuz it never passed middle between c and h on the cluster. Can it be a bad thermostat aswell?!

 

same thing jus happen to me.

make sure ur radiator isnt leaking.u can buy some bottle of liquid that seals any holes there might be at like autozone or something

i had to learn the hard way and messed up my head and had to get it rebuilt

 

make sure the fan comes on as well when it starts to get hot. yes, t-stat could be bad but check fans n cap first

 

Damn you serious n how you fix the overheating?
And wat happen to your head?!

 

Fans work because they turn on as soon as I turn ignition key to on.
And as for the cap I'll just replace it. How do I test out the thermostat?

 

throw the thermostat in a pot of water on the stove until it heats up to temperature. once its at proper temp take the thermostat out and you can see it closing slowly once you take it out of water. if it just stays shut even after reaching temp then the thermostat is bad.

 

check the temp that it starts to open at

 

my bad. dont forget to throw the meat thermometer in the water as well

 

While ur t-stat out u should run it around with out it n see if u still get the overheating issue. that can help tell u if thats it or not

I'm having the same problem wit my other car, '04 v6 sonata. Overheated so i changed t-stat, still got slightly hot sometimes, changed radiator, nothing fixed, took t-stat out... nothing, if its not water pump then its probably gonna be h-gasket, which i pray on that car its not the h-gasket(s).

So it may take a lil time to figure ur out but it can only be a couple things so i'm sure we can all figure it out for u.

 

is it possible your radiator fluid is too diluted? if there's too much water in there it will start to boil out and come through your overflow tank just as you describe.

 

Actually it shouldn't even hit boiling point, the cooling system is supposed to operate below boiling point. You can run 100% water n be just fine with a proper operating cooling system.

 

I would definitly never put that stuff in my car.. Just replace the radiator if it leaks. All that gunk in those bottles runs through the whole system clogging up other things than your leak.

 

it can and it will. if you think the coolant temperatures within the engine don't meet and surpass 212F with ease, you're out of your mind.

i have accidentally over diluted my coolant once before and i can tell you it will definitely boil and find its way out through the overflow tank. i drained the system and refilled it with the proper mix of coolant and i i haven't had a problem since.

 

usually if its coming out from the overflow (somethings gotta be getting in to push the fluid out right?) its usually exhaust getting in from the head (bad head gasket). Best bet take out the thermostat and run it, if it still over heats and your water pump isnt leaking, you need a HG.

 

Iv'e ran my cooling system wit pure water for a couple months before n know at least a dozen others who have as well, not including some of our customers who do it n i have never had it "boil over" nor have heard of them havin it boil over from it, as long as the rest of the cooling system is in proper working order

 

check the hinges of the radiator, where it screws to the body. Mine blew up couple weeks ago; drain the radiator, refill it and test again; replace the cap and see if the fans turn on. Check the oil to see if it is pure oil or it looks kind of milky; if it is, it is your HG at least.

 

Using pure water is dumb.. at least tap water anyhow. Sorry, but it is.
Tap water has minerals and stuff in it that will bond to your cooling system internals and inhibit heat transfer/cooling.
Water also is a primary agent to promoting rust in your cooling system.

Since coolant is slippery most race events do not allow it to be used - makes the track slippery if you leak.
Race cars use straight water, but not tap water. Use distilled water (not filtered, mountain spring, flavored, etc) - it has no minerals and junk. Then add water-wetter to that.
(BTW: search the internet for 'exploding water'. Heating distilled water does not boil like regular water - it becomes super heated. People have microwaved it for tea or whatever and placing a spoon in the water causes it to exploded! Alright... done with my 'Bill Nye the Science Guy' moment.)

Coolant is a safeguard for your engine. There is no reason not to use it on a daily driver. Pure water starts boiling at 212. Closing the system and adding a radiator cap raises the boiling point. Coolant raises the boiling point as well. It also helps stabilize the water so it doesn't 'pre-boil' or flash boil when tries to vaporize as it touches off metal that is very hot.

Coolant also helps keep the cooling system in good condition. A race motor will be torn down a lot so who cares, but a daily driver uses the lubrication properties of the coolant to help keep seals in good condition and the water pump lubricated. Does pure water do that? NO.

 

I AGREE

 

I definitely agree as well, I was not trying to say that using straight water is something that should be done, I was just saying that "coolant that is too diluted" as someone previously stated shouldn't just boil out for no reason.

 

i fixed the overheating with a new radiator

and i f'd up the head bad

ahad to get it resurfaced and rebuilt =/