A little background first. Those who know about these little motors know there is a water bypass plate right above the anti cavitation plate. When I first got this motor I wasn't sure what this plate was for but I had a feeling it had to do with the water intake. My suspicions were proven true when I was running in a barrel and allowed the water level to slowly go down until the plate was exposed and the pisser ran dry. I shut it off immediately of course. So with this in mind...

From bracket to cav plate is 17" and my transom is 16". Everything I've read about proper mounting says the cav plate and keel should be as close to level as possible so that the cav plate will ride the surface of the water at high speed. That's all fine and good till I thought about that water plate. If the cav plate is on the surface, the water plate will be out of the water.

What should I do? Leave it an inch low? Or will the plate being exposed not matter when going at speed?

When I ran a 9.9 on my 16.5 foot bass boat I built a jack plate and the best height performance wise was having the cav plate even with bottom of hull

1" will not make any difference with a standard shaft 9.9 hp OB.

Tom