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Author Topic: Engine Shaft length ?  (Read 594 times)

November 30, 2013, 11:31:53 PM
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c bishop

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Engine Shaft length ?
« on: November 30, 2013, 11:31:53 PM »
redoing a 70 22' flatback, were closing in the transom and going with a port bracket…..the boat has a 25inch transom , so my question is do i need a 20 or 25 inch shaft motor…I was thinking a 20 inch shaft would be ok since the port bracket has 12 inches of lift so it just depends on how high or low we mount the porta bracket on the transom ……is this right or do I need a 25 inch shaft motor ?

Any and all help is appreciated  

Thanks
Cody

November 30, 2013, 11:36:54 PM
Reply #1

wingtime

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Re: Engine Shaft length ?
« Reply #1 on: November 30, 2013, 11:36:54 PM »
Keep in mind that for every 12" you move the outboard aft of the transom you have to raise it 1".  Any reputable bracket manufacturer will build that into the design of the bracket.
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December 01, 2013, 09:27:39 AM
Reply #2

seabob4

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Re: Engine Shaft length ?
« Reply #2 on: December 01, 2013, 09:27:39 AM »
Go with the 25", it's what the transom was designed for, regardless of Porta Bracket, Armstrong bracket, whatever. That and the fact that in the 150-225 HP range, which is what you'll probably be putting on the boat, you're not gonna find a whole lot of 20" shaft models out there in the used market...


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December 01, 2013, 10:30:16 AM
Reply #3

GoneFission

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Re: Engine Shaft length ?
« Reply #3 on: December 01, 2013, 10:30:16 AM »
What Bob said...    :salut:   Plus, it's good to have the powerhead higher up out of the water.  Cut the throttle and watch what happens with a 20" motor - some of them are almost under water when the stern swell comes up on the transom.  Heck, I would even consider a 30" just to keep things high and dry...
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December 01, 2013, 11:10:22 AM
Reply #4

c bishop

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Re: Engine Shaft length ?
« Reply #4 on: December 01, 2013, 11:10:22 AM »
Thanks for the help guys , I guess we'll be going with a 25' inch motor

 


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