Mounting kicker

[Rranger]

I have a Fiberform 21 foot that I want to mount a new 25 hp evinrude etec with a 25 inch shaft and electric tilt for a kicker. Main power is 5.7. I bought a Vance jack plate with a 5 inch adjustable lift. On the port side of the boat where I want to mount it its 35 inches from the gunnell rubber to the bottom of the transom.
Question is basically where? Is the cavitation plate basically even with the bottom of the transom where it hangs? And should the jack plate be adjusted in the center of the lift so I have 2.5 inches play up or down after mounting, or all the way up or down? Thanks.

 

[Rranger]

No Title

Better pic

 

[JimS123]

Its only a kicker so it won't plane the boat. Thus, the cav plate position is not that critical. The prop just needs to be below the bottom of the boat when running. I'd adjust it as high as possible.

Wherever you put it, since you didn't buy a retractable bracket the motor will need to be able tilt up to get it out of the water.

Assemble it all on the ground to make measurements, and then install it in the center holes, so you can move it up or down in case an adjustment is necessary.

All this may be a moot point since it looks like your trim tab will be in the way, preventing installatrion.

 

[ondarvr]

25HP is a bit big for a kicker on a 21' boat, most people use much smaller motors, but there could be reasons to go with one that size.

The deeper the prop the better it will perform and the less likelihood the prop will rise out of the water when the waves get big, but it will work OK with the center of the prop shaft inline with the hull, maybe even higher depending on how far the prop is behind the transom. The lower it is the better it will perform in reverse too. The anti-ventilation plate height isn't that important in this application

 

[Rranger]

I'm using the 25 hp because it's paid for lol. And I use it on my 14 ft aluminum polar Kraft and troll with it. Those Etec's idle right down. The other reason is if my big motor craters I want some juice in the second engine. My bracket has a 12 inch setback plus they made me up 2 inch spacers just in case for tilting up. I'm hoping that also clears the trim tabs.
What's the norm for kickers and trim tabs.?

 

[ondarvr]

I don't think there's any rule of thumb for kicker to trim tab distance, mine is rather close, and it performed better before the tabs were in place, but still does OK now. The deeper you go, the less of an issue it will be.

Paid for, and being used on another boat is about the best reason there is.