My Son took out the boat last Sunday and came home with a blown wet exhaust failure which I can assume was caused by the engine overheating. I removed the riser and did not see any signs of a blockage. The risers and exhaust manifolds where replaced by me last fall so they looked brand new inside and outside. The exhaust does exit thru the transom into 4 inch stainless steel exhaust tubes. On this side that had the blown hole was also missing the metal flapper. When I had the riser removed from the exhaust manifold I decided to start the motor to check and see if I got any water coming out the top of the manifold. Large amounts of water came out. Before replacing the wet exhaust tube what else should I look for that might have caused the motor to overheat enough to burn out the rubber tubing or should I just keep an eye on the water temperature gauge?
