Motor bogging down shortly after running full throttle.

Thanks for the help, I wish I would have put on that new prop I had on hold but after the guy said mine looked fine I figured I'd save the money. Do you think I should go with a direct replacement of the 10.5 x 11 or go to a 10.5 x 9 ? Do you think I should replace just the impellor or buy the hole kit? Any manuals in particuliar you suggest? When I took the prop off last wkend I dont recall seeing anything that resembled a "thrust washer" that I read about in my small engine book that came with the boat. Any thoughts on this? Thanks

 

Visual inspection doesn't tell you much about the rubber slip hub on the prop. If it's failed, it will still look fine until you actually dismantle the prop hub.
From your earlier posts it looks like you're over-propped anyway and so replacing with the same 11" pitch probably wouldn't be a good idea; I'd try the 9".
The only parts in the water pump that tend to go are the impeller and gasket. The housing will be fine unless you regularly run it up on sandbars.

 

A thrust washer is a stepped washer ,quite thick say 4mm. As the prop is rubber bushed ( you now know that) the prop will give slightly under thrust and stop on the washer. The washer will then ,---take the thrust.

If you dont have this it will mean that the prop thrusts on its rubber cush drive and could touch the drive housing.

The idea of the cush drive is shock absorbing and forgiving gear selection. Once selected its job is done. Appart from driving the prop!!

 

My main interest when I get through this is to hopefully gain some top end speed. How much speed would you guess I'd lose if I go with a lower pitch ( 9" ). Or should I be more concerned about getting the right prop (sized right to my WOT rpms) regardless of my speed loss ? I will check for the thrust washer but I dont remember seeing it when I took the prop off. Is this something I can probable get from the same marina store that has my prop or should I look into a special order now? I will also go ahead and get the water pump kit but I want to get a manual that is more specific to my engine instead of a generac one that covers many like they seem to have in the supply stores. I have read that Ken Cook Company is a good source for this but I'd like to have one sooner than a mail order, do you suggest any other sources? Thanks again.

 

On this boat you should be worried mainly about getting your engine properly loaded, and running in its correct RPM range. An overloaded engine is always a bad thing.
High speed and low-powered pontoon boats don't usually mix.

 

Im reading the outboard posts to tryin learn,so what was the problem?impeller?