Intermittent Overheating

[GoBig]

'03 210 SANTE EX330
Started intermittently overheating over the weekend. It would run fine for several sessions, then the temp would spike, I'd shut it down for 10 minutes and it would run fine again for a couple of hours then would overheat again. I finally just put it back on the trailer and called it a day.
*I have not checked my impeller yet but it was replaced less than 20 hours ago (I don't believe it's the impeller given that it would run fine for so long before overheating again).
*Raw water intake and filter is clear
*Both belts tight and okay
*I'm getting hot water out of my shower

It "feels" like something is blocked somewhere but my intake filter is clear.

Any thoughts? Where to start?

[behindpropellers]

RWP leaking through the bearings?.....Forget that its a GM motor.

[Miljack]

Check the fittings on the water strainer to make sure they are not pulling air. If the strainer is allowing air in, the raw water pump will not pull water, but air. This will also start to tear up your impeller.
I had this problem last year, at first could diagnose the impeller was bad as it had eaten up the back half of the impeller, took pulling the impeller out of the pump to inspect.

[WakeSlayer]

You should go through all of your hose clamps regularly with a 5/16" nut driver, or a small ratchet. You will find a couple every time that need tightening. These small leaks contribute to bigger temp problems. I do this at least once a season, sometimes twice.

[Miljack]

Mike,
that's because your engine is a rattlepot.... ;-))

[WakeSlayer]

Jack, I think yours is a rattle pot!!!