After a couple of years of ownership of my W30 Westerbeke it has never over heated but the gauge's final temperature reading is 230 degrees and it stays between 185 and 230 sometimes getting close to the end when running @ 1800 rpm, I've searched all my manuals and can only find a thermostat rating of 175 to 183 so I know when the themostat is opening.It seems that its running very close to overheating for my comfort range (but maybe the gauge is wrong) and I've checked the heat exchanger for blockaged and its pumping plenty of raw water so now I'm ready to install a new mechanical temperature gauge and remove the old electric sender and gauge and I'll have a true reading of what the engine is running at, if any one has some input so I have a bench mark would be helpful.