EvilZ wrote:
I'm not understanding the rationale of flushing the engine before use....Is it to clear the cooling system?
After using in salt water, sure flush well - but if it lives in the salt water, flushing isn't going to do much. Maybe if you have a flush port, you could at least flush the engine block.
+1. I have no idea how flushing the engine could make anything work better, and in any case, yes, flushing before every use shouldn't be necessary at all (flushing after use to get rid of salt water is a good thing though). Your sense of dragging something (I'm assuming here that you know what that would feel like) along with what sounds like dramatically excessive fuel consumption is intriguing. What range of speeds & RPM's are you in during these short runs prior to the beeps? Has the dealer verified that the temperature at the sender actually matches the gauge? Have they verified thermostat and impeller function? Have they checked for a spun or damaged prop/hub? Checked exhaust tubes for obstructions?
Electrical corrosion is certainly something you have to stay ahead of with a boat, but I don't think that's the problem here unless it's with a sender connection (or sender).