This boat is new to me and I am unsure as to how much water should be movig through the exhaust. Certainly it does NOT spit out the amount of water my Mastercraft's water does. The boat does not overheat, I have put 30 hrs on it on a recent travel to my new port of slipping (I had 2 no wind days on Lake Michigan). The guage did not go higher than 135-140, however, the amount of water exiting the exhaust has raised question to other's who have looked at my boat. "Some" water comes out, it just doesn't gush. I will check the impellor, perhaps the marina did not actually change it as they indicated. In reading I noticed that perhaps I should clean the raw water echange for the exhaust manifold??? Perhaps I really do not have a problem and this is just the way this engine operates???