06 450 over heated due to loss of all coolant during race. Bike stalled out and was pushed back to pits. Replaced bad o ring on radiator now all coolant is coming out of drain hole on waterpump cover..What type of problems am I looking at. I havent taken cover off yet. Im hoping all it needs is a new gasket or seal. How big of a job could this turn into? Bike started after first kick today then I noticed coolant leaking out.