1989 searay 21ft 4.3 bogging and blowby at W.O.T only.

[Faison80]

Pulled the engine waterpump off yesterday and removed the back cover, removed the impellar and found a place as big as a nickle eroded away, and was pitted and worn all the way around. Could this cause poor circulation in block and caues the high cylinder temps ive been having?

 

[alldodge]

Pulled the engine waterpump off yesterday and removed the back cover, removed the impellar and found a place as big as a nickle eroded away, and was pitted and worn all the way around. Could this cause poor circulation in block and caues the high cylinder temps ive been having?

Yep, that would do it.
The water pumps on boats are positive displacement type, which means that have to have complete positive contact on all surfaces to pump correctly.

 

[Faison80]

I'm thinking this has been causing exssevie heat in the block causing me to think im lean or way advanced. Had no idea the waterpump was that bad.

 

[alldodge]

I'm thinking this has been causing exssevie heat in the block causing me to think im lean or way advanced. Had no idea the waterpump was that bad.

I don't see extra heat causing you to loose pieces of your engine out the exhaust. The extra heat if under 200 degrees IMO would not cause what your seeing

 

[500dollar744ti]

You have a pretty simple diagnostic process..

Run engine from remote gas tank- If problem is gone, your tank, lines or check valves are bad. If problem remains, it's either at the fuel pump or beyond the fuel pump.

Test fuel pump pressure- If pressure is wrong, fix that issue. If pressure is within spec and you verify fuel is flowing out of the carb fuel fitting, you need to fix your carb or replace it.