hello I recieved alot of help from this forum . currently I am trying to diagnose an overheating issue . at idel my temp climbs up to 200 around 1200 rpm the temp is at normal opperating temp 165 however anything over 1200 rpm and the engine will over heat again impeller was changed 6months ago on the raw water intake thermostat was installed . (when the boat was purchased there was no thermostat) I have removed the outdrive after reading the raw water intake hose will colapse on itself through corrosion . however the hose appers new with no blockage . my attempt now is to check hoses for debris,change thermostat again, and install anoth imperller while I am at it . any suggestions out there on what else I should consider? 350 mag mercruiser with bravo 3 outdrive .