Prop Ventilation

[Noah Genda]

I thought I was the victim of cavitation. The more I have read, it sounds like ventilation is the cullprit. One of the things I love about my Bennington 2575 tritoon (express package) is how it can turn sharply and not lose power - or so I thought. When I had about 9 adults on board pulling a tube, if I wasn't careful, I began to lose power and hear what appeared to be the motor racing. I don't ever remember that happening before, and my passengers thought something was wrong with the motor. What role does weight play in ventilation and tight turning? Thanks in advance.

 

[cwag911]

If you had a lot of people on board, and more of them towards the bow, then I would suspect you lost the bite on the prop, especially if you were in a turn.

 

[kaydano]

I've had the same problem. My thought is the short center tube stirs up the water ahead of the prop a bit much on occasion causing the ventilation. I was wondering if an aftermarket foil would help. The heavier the load the more it happens, but most only in a turn like you said. The look on some faces is priceless, especially when I give a funny look back!

 

[RiverBill]

Noah Genda,

You need to trim down the drive to keep it from cavitating. Most people trim the drive up to increase speed, during turns the prop will lose it's bite and cavitate! You need to find the sweet spot on the trim gauge where the speed is good and the prop doesn't cavitate during turns. Make small adjustments to the trim up or down when the boat load changes. Also different props (3 blade/4 blade) can change the performance of the boat with regards to cavitation.

RiverBill