Re: air and water cooled motors?
Depending on your type of motor, the water pump is usually used to cool the exhaust gases and the lower leg, while the powerhead is air-cooled like a lawnmower engine. In air-cooled engines wih a water pump, the lower leg will fry if the water pump goes out. Some air-cooled engines do not rout the exhaust thru the lower leg but use a separate pipe that can heat up without hurting anything. Depends on your type of motor.