Shaft Length

[Bozol]

Hello,

Im looking to buy a 90hp 4 stroke Yamaha for my Boston Whaler and want confirmation on which shaft length to buy.

The engine comes with a 20 or 25 inch shaft. I think the one I want is the 20(the transom is 22 inches top to bottom). Any advice would be greatly appreciated.

Cheers,

Bozol

 

[cemiiii]

Re: Shaft Length

I defer to the more experienced, but generally I've always believed that you should shoot for ideal placement of the anti-ventilation plate (first plate above the prop on the outboard) flush with the plane of the bottom of the boat. Often you will find that the actual length of a standard 20" shaft is actually about 22" as measured from the a/v plate to the top rear of the transom mount. If you can, verify this length on your motor, or to be purchased motor either with the manufactuer or in a showroom.

I'm afraid that if you'd get the 25, you'd probably need a jack plate to get optimum performance.

Please supercede this advice with that offered by a higher ranking respondee.

chris.