I've opened the bonnet of my mk1 s-reg fiat punto and filled up the screenwash container. unfortunately, the day before i did it wrong, and i mistook the container at the front of the engine for the screenwash container, and i filled it full of water and screenwash. what is this container? is it part of the coolant system? have i caused irreparable damage? the level has not altered, yet.
sounds like you have filled the radiator expansion header to the top (container is on the front right of the engine as you look?) you need to syphon some out until its about 6 inch down, should be a max mark on it
dave