coolant steam!

[lowrider]

After a sporty drive home tonight I parked up to find steam coming form the coolant overflow tank,around the cap.Whilst this was happening the temperature sensor remained unchanged(in the middle) It settled after I switched off the engine and even though it steamed heavily the coolant level has not altered much.

Help

[shent9]

tighten the cap?

[lowrider]

Cap is on tight.It is a push down(not screw type)

[ScottyBoy]

If you have slightly to much in there this will happen. aslong as the temp gauge does not move above normal then you will be fine.

Even with a screw cap on an MCS this happens my coolant tank is always discoloured

[cars-r-me]

There is a common fault with the bottle ,The seam splits round the middle of bottle were it's stuck together

[lowrider]

Checked the expansion tank this morning. It was empty! Filled it to max and drove to work. empty again. Filled it and it stayed at the max level but when I drove home and parked the coolant started to bubble from the pipe connected to the bottom right of the expansion tank the coolant level rose and it started to boil over.I switched off the engine and it settled but there is now coolant right up to the cap.After a few hours this dropped to the min. level. Could this be an air lock? Advice appreciated

[BJM]

Could be a knackered thermostat.

When the engine is hot - is the radiator also hot?

[PK5]

I agree with bjm, do a check on the thermostat