Bad Overheating Problem

[pat656]

Ok, I would check your impeller AGAIN. You may have sucked up some garbage and your impeller is shredded again. Did you idle your boat out of water for any extended amount of time? Anytime you have overheating problems at idle it usually means the impeller is shredded. The reason why you don't overheat when moving is because the water is being pushed thru the cooling system by pressure. I could almost put money on it that your impeller is chewed up. Go to your boat now and take off the plate to the impeller housing, pull out the impeller with a needle nose and inspect it.

The boat has not been turned on while out of the water. I checked the impeller and its fine.

Can you tell if it is really running hot? It may be a temperature sensor issue indicating a false temp. If it thinks its too hot it probably won't let you crank it.

When you had the impeller replaced, did they give you the old one? Was it missing any blades? I've seen those break off and go inside the engine block and get hung up in the Exhaust Manifolds. That will limit water flow through the engine as it can't escape through the exhaust.

Take your board off the back and have someone drive as you watch the exhaust ports coming out the back. You should be able to see equal amounts of water coming out each pipe along with the exhaust. Its not going to be a full pipe of water or anything like that but you can see water coming out. That is how I new I had something plugged on my old Malibu. In my case it was getting so hot it was melting the exhaust hose coming off the manifolds, but I had zero water flow out of one pipe....

i could tell it was hot because all of the hoses were burning hot and had scalding water in them (took them off while in the water) and I took the one off the water pump and cool water sprayed out but there is no blockage in any of the pipes, i checked.
I tried to start the boat when the temp read 135 degrees, it was not hot at the time. we cut if on and off while at 200 degrees and it started right up
i did get the old impeller and it was not broken or torn.