2002 Grand Cherokee
Was at idle yesterday and “check gauges” came on, temp reached about 230, a loud noise that sounded like a dying cat started and continued after i turned the engine off. I got smoke from under the hood, popped the hood and coolant reservoir was open and spewing everywhere. any ideas? Check the pressure today and that was good with nothing leaking.

 

The dying cat sound was steam bypassing the radiator cap and entering the reservoir. In order for steam to form, the pressure in the system had to be over the 16-18 lb limit caused by air pockets in the water jacket. Once the coolant begins to boil, pressure goes up exponentially. All it takes for this chain reaction to happen is the coolant in the reservoir to get low enough for air the enter the system when it cools down. A slow leak at the water pump bearing over time can cause this or a suddenly blown head gasket. Check your oil pan for coolant. If it's not mixed yet, you can pull a sample at the drain plug after it's set awhile and the first thing to come out will be coolant. Hopefully, you were just low on coolant.

 

This is exactly what happened at Chernobyl.

 

No, Chernobyl happened because some idiot turned off the emergency stand-by pumps and nobody caught it before the meltdown started. PLUS the Russians don't build reactors with containment vessels. EVEN ON SUBMARINES!

 

Heh well there's way more to it than that, if you ever want to go to wiki or something and read the account it's pretty hairy. A confluence of converging errors.

 

Mostly a convergence of arrogance.

On top of a ton of bad decisions which are typical of police states.


But we digress!