The pump pressure is not a factor. If the vent hose is pinched (probably under the battery) or mistakenly plugged as a rouge vacuum line, the hot fluid can not move into the side cover area via the thermo-plastic valve (a better idea). Clear the vent line and move the open end up near the top of the batter4y and you will be fine.
Clean up all of the fluid to prevent and engine fire and top her off.
Note that the cold fill mark is the â??hiâ? mark and the hot fill is the â??lowâ?? dipstick mark due to the action of the valve.
jeff
