My 5.7EFI Bravo III was just fixed with a new raw water pump. I took the boat out when after idle speed for awhile I went on WOT when the engine went on half RPMs ( I think this is a safety item I can't find in the service manual book anywhere) and the alarm went off. I thought it might have been a plastic bag caught on the water intake. I shut it off and then turned it back on and returned to ramp. It ran fine so I continued on my trip at all speeds for about 2 hours. Boat ran great. Temperature gages where 150 to 175 degrees. I returned to the ramp when I decided to put it in neutral and rev up the engine. The alarm when on again. I took boat out flushed the sea water and flow was very good coming out of exhaust? What could it be? My alarm or belts to loose or what?