Overheated on track - now what?

[Pete_89T2]

Originally Posted by infernosg

That all makes sense, but the problem I'm having is with the car on and the radiator cap off I get a lot of coolant coming up and spilling out. Maybe there was just a large air bubble pushing it all out but the pessimist in me says this is the pressure from the combustion chamber. Maybe another picture will suffice...

I forgot to mention that I remove the radiator cap after the coolant is at operating temp and circulating thru the engine - this helps avoid most of the spilling, since once it's all circulating, the level in the rad should drop a bit. But yeah, if you remove the cap while its still cold and run the engine with the cap off after just filling the radiator, lots of coolant will barf out. Just use a thick rag to keep from burning yourself, crack open the cap to the first stop to release the pressure, let any excess coolant bleed out then remove it all the way.