Well, got pretty good use out of the boat this summer, and was just gearing up for the fall perch. But, am having trouble with the motor overheating. My motor is a MercCruiser i/o unit. Last week headed out to the water intake for perch, and didn't get much over a mile offshore, when it overheated and started to steam. Idled it back down to around 1000rpm, and got back to the marina, and the themp guage dropped back to normal. Mechanic at the marina suggested that the water pick up screen might be plugged with algea or zebra mussle's.
So raised the outdrive unit, scrubbed the screen off, and took a pick, as the mechanic suggested, and make sure the holes are clean. Went out into the lake, but not very far, and it overheated again. This time the temp guage stayed hot, so am wondering if maybe the thermostat might have went bad. The boat is 30 years old, and as far as I know, it's never been replaced. Any suggestions? Thanks-gypsyman