CrazyDude

Hey guys, you might have seen/read my other two posts about my 91 NA that has had a couple of overheating problems (neither of the times did the heat get above the colored region on the gauge). Anyway, today when I started the monster up, I had the digital camera handy, so i snapped a pic of this:



It happens now and again, usually only coughs smoke like that for a couple seconds, smokes lightly for ~20 seconds, but it runs strong after that. Mileage seems a bit low, but I havent verified that yet.

So, how bad is this? It looks like collant, no? Does this mean my engine is going to implode soon?

flubyux2

usually white smoke is caused by coolant. next time it happens, walk thru the cloud of smoke and see if it smells somewhat sweet, like coolant does. if it smells even Faintly sweet, its coolant.

theres probably a bad o ring or something or maybe water seal. and what could be happing is after you drive it, and its got some heat in the engine, and the thermostat has opened, then the coolant system is probably under pressure, never more than 13-15 psi though, otherwise the rad cap would release. anyhow, if its a small leak, the combustion pressure would force the coolant back thru the leak, and force combustion gasses into the coolant jacket. BUT, after you shut the motor down, the combustion pressures cease, and now your cooling system is still under pressure. now the coolant is forced thru this small leak under its own residual pressure, into the combustion chambers inside the motor, and sits there till you start it up the next time. thus, the result is the small bit of coolant which seeped past the gasket being burned off, hence your white cloud that lasts for 20 seconds.

what to do about it? rebuild i guess...

chris

Edit: btw, the mileage is probably low since the combustion gases leaking into the cooling system arent being harness to actually DRIVE the car. so it takes more throttle to compensate for this lack of power. more throttle equals less gas, this usually leads to more power. not in this case, its all leaking off into your cooling system.

thats Also why it over heats, you have SUPER HOT combustion gasses entering your cooling system. and its SUPER heating the coolant, so your temp sensor says its hot. go figure.

7Rebel

Most older 7's smoke at startup so I would doubt that your engine is bad. My 7 has been smoking a little at startup since I got it in 2000. But I wouldn't drive it until you find out why it is overheating.

George