running HOT... with engine OFF.

[gransport_talon]

i recently rebuild my engine, everything has been changed. i've ran into one problem, it seems everytime i run the car for a 15+ minute drive... mind you the car drives at 194-201 degrees, hits 209 at idle... then the fans come on and drops again... now when i shut off my car i am hitting damn near 230 (229 to be precise) at which point i pop my hood to assist the cooling down...

now, i know this probably means air bubbles inside the system, now i've heard of boost leaking through the HG into a water jacket? thats worst case scenerio, but in that case wouldn't i also be puffing white smoke out my exhaust (in which case i am NOT).

i am losing coolant through the overflow bottle, and there is actually another leak not far back from it... its leaking onto the tranny, looks like where the hose that runs to the overflow might not be on there tight enough and leaking, or something else in that area..

or of course there is a chance i just did burp the system enough, but i don't really think that... any takers?? thanks

 

[Defiant]

When shut off? That'd be heat soak. Is that a new thermostat? New radiator cap?

 

[ITSME4G63]

If you rebuild your car maybe you should change out the old thermostat, Get a 180 degree thermostat from autozone or murrays , check hoses for leaks! when your car is on, pop the hood and press the throttle inside the engine bay and look aroudn if any hoses are leaking, also, using radiator fluid, do not use the orange stuff! Its meant for gm cars only, get prestone quickfill (green stuff) or get a radiator fluid that is not mixed 50/50 but 100% radiator fluid, drain your radiator, fill the radiator with the whole bottle, then top it off with water. last, changeyour radiator cap because they tend to give out after a couple years , a 1.3 bar from greddy or blitz or any 1.3 would probably do.

 

[Ethanthegod9]

The leaks you speak of sound to be a part problem. If the coolant is allowed to depressureize then it will boil at a much lower point. Boiling liquid does not cool off anything. Fix the leaks and do what ITSME4G63 said. Check with people in your area to see what mix of coolant / water they are using. Prestone or Peak work well. Also try using distilled water, it's seems to make a positive difference. WaterWetter from Redline is a great product put in 1 bottle. hope things go well.

 

[gransport_talon]

its still the old thermostat, so i should try and change it out with a 180? could it maybe be sticky and not working properly? i have two rad caps, one off my turbo motor and one off my old car's NT motor... i've tried both, the only thing is, the upper IC pipe is so close to the cap (f'n ABS ) that under boost, as any pipe it moves a bit, hits the cap and moves... but not much, you know the two tits(sorry only thing i can think of. ) on each side, well it moves it about a length of a tit off. (so maybe 3/8" of an inch)

could that be doing it as well?

 

[ITSME4G63]

replace the radiator cap...

 

[gransport_talon]

i replaced my cap, thermostat(180*), gasket, and added more anti-freeze, and fixed my leaks, and my overflow bottle was not overflowing this time... but at shutdown my engine still hit 217.. which i know isn't very much... but it worries me come summer time next year when it'll be 80-90 degrees here compared to the 60 that is now... not to mention the FMIC i will have, maybe i'll just have to go to a 160 next year...

 

[Defiant]

Okay, a crucial thing to learn here: a lower thermostat has no effect on the running temperature of an engine until you get into really cold weather. A thermostat is to get an engine to warm up quickly, and then keep the running temps UP to a certain level, and DSMs don't like to run cold. Once a thermostat opens, it's not going to open up any more: "open" is "open".

How the devil did you replace "everything" and re-use a $4 thermostat?

Now, replace the radiator cap with a NEW one.

Stay with the factory-spec thermostat.

Your engine will continue to heatsoak when shut off until you move to Antarctica.

I dream of having 90° summers. All the cars out here (and, places where it gets really hot) do just fine with factory-spec thermostats.

 

[ITSME4G63]

I look at his location, and he's in canada, so naturally you have colder weather there, you shouldn't be worried if you replaced the thermostat and radiator cap, and flush you rradiator, dont just fill it up, flush it, drain the whoel thing then hose it down with water to make sure EVERYTHING is gone from it. then fill it up with proper fluid, what I said earlier. Stock thermostat is 195 I believe, I used a 180, I think the 2g's come with 180 stock, and I used a 1.3 bar cap instead of stock 0.9, seems to work very well on my car, I do not have a fmic...yet.

 

[gransport_talon]

my problem apears to be fixed now, after a night of moderately hard driving, i never once puked coolant out of my overflow, and temps always stayed within reason, obviously getting a little warmer once the car is still and off.. but its not boiling over and puking out anymore, my old cap was finished it wasn't sealing very well... the one works great!

oh, and i re-used the old thermostat for no perticular reason, just never really thought about it i guess.

thanks guys

 

[leakyfaucet]

a lower thermostat has no effect on the running temperature of an engine until you get into really cold weather.

I disagree.

 

[Defiant]

I disagree.

Okay, let's think it out.

If you have a 195° thermostat, and the running temperature of the engine is 200°, how could a 180° thermostat have an effect on that 200°?

A thermostat rated at 195° will be fully open before the engine reaches its operating temperature.

So will the 180°, but it won't be any further open, as "open" is "open".

However, if the engine is intended to operate at 200°, and the radiator is in cold enough air that it can cool the coolant down to 190°, then the 195° thermostat will reduce its opening aperature so that the temperature will come back up to 195°, where it will stay until the cooling conditions change. But the 180° thermostat won't begin to close, so the engine that wants to see 200° will now be running at 190°, ten degrees below its intended operating range instead of the five degrees the intended thermostat would hold it at. And the operating temperature would continue to drop until it was below 180° and the too-cool thermostat finally begins to regulate flow and heat transfer.

Now, getting out of winter and back to summer running, the running temperature is a matter of how much heat can be carried off by the cooling system- size of radiator, flow of air through radiator, water pump capability and overall cooling passage design. If the engine is supposed to run at 200°, it's up to the thermostat to keep out of the way so that the coolant can carry enough heat to the radiator which is supposed to reject it in sufficient quantity that the engine won't exceed its designed operating temperature. A "cooler" thermostat can't make a radiator shed more heat.

The third condition is cold-engine startup. The thermostat restricts coolant flow through the radiator until the coolant in the engine block and head (and heater core, in DSMs) is up to the thermostat's rating. If you're running a 180° thermostat, an engine that wants 200° will never warm up properly, as the coolant starts to flow through the radiator and carries off heat before it's up to temperature.

If an engine's cooling is improved by a lower-temperature thermostat, then it doesn't have enough radiator -or, pehaps its radiator is being blocked by an intercooler or the like.

Your retort is awaited.

 

[loreak]

I agree with defiant, the engine runs at 200+ degrees, and as soon as you hit 195 its open the whole time so unless its dropping down to the point where your thermostat is closing a cooler thermostat wont have any effect on cooling. An engine running 200 degrees cant tell the difference between a 195 thermostat and a 165 thermostat. If you have an upgraded intercooler with big fans, then you may be able to run a cooler thermostat and keep it lower but otherwise it runs 200+ at all times. Or maybe if its -10 out it may run colder with a lower thermostat.

My friends camaro has like a 195 thermostat i think, and his car runs 210 and he asked me if he should get a cooler thermostat, and i told him that his stock thermostat was already open, so getting a cooler one would do what? it would be...open? I told him to buy a bigger fan and a fan relay to turn it on from the car to keep temps down.

 

[dsm4life]

Okay, let's think it out.

If you have a 195° thermostat, and the running temperature of the engine is 200°, how could a 180° thermostat have an effect on that 200°?

A thermostat rated at 195° will be fully open before the engine reaches its operating temperature.

So will the 180°, but it won't be any further open, as "open" is "open".

However, if the engine is intended to operate at 200°, and the radiator is in cold enough air that it can cool the coolant down to 190°, then the 195° thermostat will reduce its opening aperature so that the temperature will come back up to 195°, where it will stay until the cooling conditions change. But the 180° thermostat won't begin to close, so the engine that wants to see 200° will now be running at 190°, ten degrees below its intended operating range instead of the five degrees the intended thermostat would hold it at. And the operating temperature would continue to drop until it was below 180° and the too-cool thermostat finally begins to regulate flow and heat transfer.

Now, getting out of winter and back to summer running, the running temperature is a matter of how much heat can be carried off by the cooling system- size of radiator, flow of air through radiator, water pump capability and overall cooling passage design. If the engine is supposed to run at 200°, it's up to the thermostat to keep out of the way so that the coolant can carry enough heat to the radiator which is supposed to reject it in sufficient quantity that the engine won't exceed its designed operating temperature. A "cooler" thermostat can't make a radiator shed more heat.

The third condition is cold-engine startup. The thermostat restricts coolant flow through the radiator until the coolant in the engine block and head (and heater core, in DSMs) is up to the thermostat's rating. If you're running a 180° thermostat, an engine that wants 200° will never warm up properly, as the coolant starts to flow through the radiator and carries off heat before it's up to temperature.

If an engine's cooling is improved by a lower-temperature thermostat, then it doesn't have enough radiator -or, pehaps its radiator is being blocked by an intercooler or the like.

Your retort is awaited.

this is why i dont disagree with Defiant , man i wish i had a cool owned picture right now