I have a 1971 Johnson 60 HP w/electric shift. This past weekend I shelled the impeller. I have replaced the impeller, thermostat, & added a "pee hole." Most of the time I get a steady stream but while cruising about 25 mph it stops streaming ocasionally & I get steam from the tube. Is this to be expected. I didn't have a tube before so I do know what to expect. Any help would be appreciated. I've seen some great replys to many questions.