Coolant boiling over, questions...

[eric1855]

I was AutoXing my new 325is yesterday and it was a fairly warm day about 85 or so.

The car, after i would let it cool and shut it off, in the grid, it would start puking coolant. On the tank in the engine bay, with the filler cap, there is a hose on the passenger side of it that comes off, and on my car, it goes to nothing. the coolant was coming out of this hose. Is this hose supposed to go somewhere? It hasnt done this before.

Is it a closed system? Or perhaps is my pressure cap going bad?

Anyhelp would be great apprecaited. Thanks

Eric

[reelizmpro]

Sounds like it's not holding pressure, check for cracks and try another cap.

[BahnE30]

my car did this once. i snapped the alternator belt which also runs the waterpump and fan so it got up to about 3/4 temp before i noticed it pulled over and there was a trail of coolant behind the car
it's just an overflow tube for the expansion tank. it should only do this when the car runs hot. i wouldn't be really worried about it if it did it during an autocross when your driving hard i'd keep and eye on things thou for sure

[demlotcrew]

Do you have anti freeze in the water mix?

[Spencer]

On my eta I had an overflow hose coming out of the coolant reservoir.

-Spencer

[Jand3rson]

On my eta I had an overflow hose coming out of the coolant reservoir.

-Spencer

They all do...