When I start up the outboard it takes awhile to reach operating temperature. In the mean time I see steam coming out of the "pee hole" for about 4-5 minutes and then the pee stream is weak for about 5 minutes and the water is very hot! I will stop the engine and then start up again about 2 minutes later and the pee is strong and the water is cool. I do this start up procedure before I leave for the ramp and I have the "motor flusher" on and the hose hooked up with water running. Is this normal? or should I replace the thermostat? (it is only 3 months old) Note: the outboard is a Nissan four strike 18hp. Thanks for any help.