Let me guess: When you went over the wave and the prop broke the surface, the 
engine started to race and kept racing after the prop went back down?

That is exactly what happens with an outboard in waves (separate recent 
discussion on the list) and the situation is the result of cavitation. The 
engine races because the prop has no bite on the air, and the prop just makes 
bubbles and spins when it goes back into the water. When you throttle back, the 
water flow over the prop can reattach and stop the cavitation.

Your Gori prop is geared, so it will stay with blades extended out as long as 
the prop shaft is spinning. It didn't fold when it came out of the water. And 
the advantage of the geared prop is that the blade going over the top does not 
close due to the effect of gravity. 

When traveling at "higher" boat speed, for example when coasting down as you 
approach the dock, with the engine near idle, the prop may fold slightly due to 
the water flow over the prop having more force on the blades than the thrust 
being generated by the prop spinning. But when you are going forward at idle 
speed with the transmission engaged at idle, the thrust on the blade will keep 
the blades folded out. 

That said, any folding prop does take a bit of getting used to. They all have 
idiosyncrasies compared to a fixed prop setup.

Rick Brass

Sent from my iPad

> On Feb 12, 2015, at 10:59, Wally Kowal via CnC-List <[email protected]> 
> wrote:
> 
> Alan,
> 
> I have a two-blade Gori that I took off our 30 Mk 1 years ago that you can 
> get at a good price.  We don't race and it folded once too often while my 
> wife was docking.
> 
> It is sized for an Atomic 4.  I have no idea where it is but I can look for 
> it if you are interested.
> 
> We had an interesting situation with it.  We were leaving NOTL Yacht Club, 
> motoring over the Niagara River bar into a heavy north wind which created 
> VERY tall waves, and every time the boat tipped over the top of a 
> particularly large wave, the prop would leave the water and fold instantly.  
> We had to put the transmission in neutral then shift back into forward to 
> re-open the prop.
> 
> It took a few minutes of panic to figure out what was happening.
> 
> Wally.
> Whistler II
> C&C 30 '74 out of Penetanguishene, ON
> 
> 
> From: Alan Lombard via CnC-List <[email protected]>
> To: [email protected] 
> Sent: Saturday, January 31, 2015 4:10 PM
> Subject: Re: Stus-List Folding/feathering Props
> 
> Hello Gary,
> I too have a C&C 30 and am debating either a Gori or a FlexoFold. Do you 
> remember what size Flexofold you have, and can you comment if it seems the 
> right size. The recommendation Flexofold have made to me is  2-blade 15x11R.
> Thanks,
> Alan
> 
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