Catalina 350 International Association

My temp guage climbs to 180, the snaps back and forth between 180 and 240 a few times, then settles around 240. The guage is not "pegged" at the top. There is no white smoke nor does the alarm sound...plenty of water badushing out the port. Yes the strainer has been cleared, there is flow, and a diver debrided the intake for the thru-hull.

We motor out of the channel with this nonsense...go to sail ASAP and kill the engine. On the way in I throttle 2600 with no visible or audible hints. The engine sounds fine, not hollow, plenty of "badoush" and no smoke.

Any thoughts?

thanks,-george

George, one thing I would check is the ground connection on the gauge. If you're getting a reading but it is erratic, the connection might be loose or corroded.

I 2nd Ken's suggestion on checking for a loose ground or corrosion on the gauge and sender. Also for piece of mind you can buy/borrow an IR thermometer (the point laser and pull trigger type) This should tell you if your engine is too hot or not. Pick a few places, where the temp sender is, oil pan, valve cover, block. If nothing is reading over 200 degrees you should be OK.