My boat has overheated about a month ago. It was the water pump so we put in a new pump. Boat is running fine right now. It seems like steam is coming out from exhaust. We checked oil and its perfect. Transmission is fine. Temperature is fine and everything is great. Just it never looked like this before. Someone told us it could of been because of the cold water.
Doesn't sound like it's cooling the way it should. My exhaust will get some steam if its ready for a new impeller. Have you cleared all the old impeller out of the cooling system?
The impeller is new. We usually check the hose now once in a while. We did find some pieces of the impeller and other crap stuck in it. Just sometimes there is steam and sometimes there isnt. This never happened before.
check for trash in the transmission oil cooler. It is located between the through-hull and the raw-water pump. Low water flow will cause steam to form starting intermittently and build to consistent.
Not sure about this but I'll throw it out there...... If a head gasket blew when the engine overheated..... possible leak between the water jacket & the exhaust port or a cylinder? Maybe a compression test or a leak down test are in order.
Yeah, I did a compression test. Everything was perfect. Oil and transmission is fine. When at idle there is water coming out. It mostly steams when you hit the throttle to get going.