Help with 8hp Suzuki

[fishface]

Hi. I have a 8hp suzuki (about 7 years old) pushing a 12 ft. aluminum rowboat. When i am alone, the boat planes nicely and the motor runs smoothly at all rpms. When i load the boat with another person or alot of equipment, the motor seems to hesitate off and on while it is getting up to speed. Eventually it will plane off and run smoothly without any hesitation. It seems that this hesitation is asscoiated with a change in the pitch of the noise the motor makes and occurs most frequently when it is under the heaviest load. Otherwise the motor runs perfectly. Any suggestions? Thanks!

 

[12Footer]

Re: Help with 8hp Suzuki

This sounds like a slipping prop. The prop hub may be fixin to spin-out, or it's just plain cavitating. Any dings in the hull?

 

[fishface]

Re: Help with 8hp Suzuki

Thanks for your post. No dings in the hull, although the motor comes from a different boat and i'm not sure if it took a hit before i got it. I like the idea of a prop problem or cavitation. I just took the prop off and can see the rubber o-ring between the hub and prop. It is hard to tell if there is something wrong with it. Any suggestions? Also, how would i discriminate between cavitation and a spun prop?

 

[Fouled Plug]

Re: Help with 8hp Suzuki

Is there a local dealer with a 'loaner' prop you can try? Could help you eliminate a spun hub. During cavitation you may hear increased exhaust noise from the through-hub exhaust, the spun prop probably not.