NS8B Spun Prop or CLutch?

[babylonlarry]

I took the RIB with NS8B out for a ride and she performed fine - picking up on a plane for a while, then upon opening the throttle to plane, it started slipping and revving high without coupling, throttle down well below plane RPM and it ran normally. Ran slow back to the big boat where I tied the RIB bow and stern and ran in reverse at high throttle. It ran a bit rough in high revs but I could not determine slipping, then ran her in forward and it did not slip.

Took her out again and several times in a row it picked up on a plane without slipping.

I think I might be at the beginning of a spun prop. I did not try to slip it by manually turning in gear against the engine as one reverse run made it solid for the moment. Ideas? TIA, Larry

 

[TOHATSU GURU]

Re: NS8B Spun Prop or CLutch?

In theory it could be either. Statistically...It's the prop as the clutch and/or forward gears don't go bad on small engines.

 

[pvanv]

Re: NS8B Spun Prop or CLutch?

Agree with TG. I have never seen worn out gears in these motors, unless run without lubricant. Likely a marginal rubber hub in the prop, which is temporarily "set" due to running hard in reverse.

 

[babylonlarry]

Re: NS8B Spun Prop or CLutch?

Thanks guys, I'm off to look for stock in the area for a prop.