496 Mag Overheating Issue
 

Lately, I have had some problems with overheating. So I replaced the waterpump impeller thinking that was my problem. Apperently it wasn't.

When I hook the hose up to the foot(bravo 1 drive) it is barely pumping water. The foot is not the problem. If i hook the hose up directly to the waterpump it pumps great. When I get out to the lake it doesnt pump water at all and overheats almost instantly. I back flused the foot and water flowed great.

If I take the bottom blue tab out of the seawater pump while running I can clearly see it is pumping because the water comes squirting out of it. But the water that is coming out of it goes from hot to cold, hot to cold. It is almost like the seawater pump will not prime itself. It only pumps if it is hooked up to a hose though! It does not make any sense to me.

Is something restricting the water from going into the the heat transfer? I took the heat transfer off and cleaned a bunch of shell out of it. I flushed out both of the risers. Is there a strainer anywhere? Or just how about any reason why the waterpump will not pick up the water from the lake?

The boat is an Ebbtide 2320 with a 496 Mag, and a Bravo 1 outdrive.

Please Help...

Did you backflush the oil cooler? sometimes $hit gets clogged up in there and can cause that problem....

Where is and how would I go about flushing out the oil cooler?

The water intake hose may be collapsing internally or the elbow from the inner transom assembly to the water intake hose is corroded and obstructing flow.

I had a similar problem with my OMC drive, it turned out that there was a hole in the water tube that is inside the outdrive.

Jim

I was thinking along the same lines, try hooking the hose up and not running it and see if you have any leaks. If there's a hole anywhere it'll just suck air and not prime. Keep in mind when on the hose your pressurizing the suction side.