Purchased it new, so i know its past. Seems to run fine at lower RPM's but will overheat when at 2800 to 3000 RPM's. (200+ with alarm) The boat is trailered and is always flushed after each use. On advice of the marina that services it each winter , I have replaced the thermostat the sea water pump and checked hoses & clamps. Removed drain plugs for block and exahust manifold. Found some small debris, but nothing to talk about. And yet I still have a problem. PLEASE HELP!!