Driving down the road after an hours drive the car had been running fine , heater was on a little gave it some beans then all of a sudden loads of steam then coolant came flying through the air vents , turned the heater off slowed down , and coolant running down near the water pump ,.. guessing the water pump or something has gone and its over pressurised and blown something . hopefully no other damage dipped the oil and it wasn't milky put it away and going to start investigation tomorrow , the joys of owning a cosworth !!!


has this happened to any of you before ?

 

..probably just water pump gasket ....but check if the pump seal leaks..there is a small hole on the body of the pump,,it will leak from there if the seal fails

 

The only way I can see how "loads of steam then coolant came flying through the air vents" would be if the heater matrix had sprung a leak suddenly while under pressure.
David

 

I've had the same, also been driving for an hour and everything ok. But first thing I noticed was temperature light came on. Pulled over and stopped. But already lots of steam and coolant all gone.

​​​​​​It started with a crack in a coolinghose.
Turned out head gasket was gone to. Small engine revision and replaced all hoses and new waterpump and gaskets to offcourse.

​​​​​​Hopefully it's just the waterpump for you.

greets