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Old 12-15-2011, 03:31 PM
savagescout savagescout is offline
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Jack Shaft Setup?

Hi,

I have a 26 foot half cabin sterndrive that I am restoring and am at the stage where the floor has been completely gutted and stringers/bearers are about to be replaced. I plan to power this project boat with a 220hp Mercruiser 4.2Litre turbo diesel of which I am going to be rebuilding like new.

Whilst I have the boat completely gutted, I was interested in investigating moving the engine towards amidships by approximately 2 feet to clear the transom area and allow me to fish around the engine box and run a jack shaft back to the bravo 2 drive.

What I don’t know is how to set up a jack shaft as they are very uncommon in Australia.

I presume I would need to fabricate some rear engine mounts, run the exhaust somewhere, fabricate some way of connecting a drive shaft to the rear of the engine and then in turn to the drive unit. Can anyone provide any more information as I would really appreciate some assistance during this planning/design phase.

Nick
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Old 12-15-2011, 04:49 PM
whitepointer23 whitepointer23 is offline
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google mercruiser jackshaft kits, you can buy everything you need. i have made my own but not for a mercruiser. what brand and model of boat is it.
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Old 12-15-2011, 05:25 PM
savagescout savagescout is offline
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Hi there, thanks for the reply, the boat is a Savage Scout 23 that has had a 3 foot hull extension to turn it into 26 feet.

Seeing your signature, it appears you have a Savage Lancer, so guessing we have similar boats...

I would be interested in going down the path of making one if it is achievable as the kits I have seen are $4000USD!
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Old 12-15-2011, 08:12 PM
whitepointer23 whitepointer23 is offline
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yes , thats a bit pricey.
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Old 12-15-2011, 08:38 PM
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Willallison Willallison is offline
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I almost bought a Scout once - fabulous boat - and my parents had a 26' Sonair, which was a custom build based on the Lancer hull.
I'm guessing that you are installing the diesel because you've managed to aquire one for not much $, but have you ever thought of putting an outboard on the back instead? That would free up an enormous amount of cockpit space (admittedly not around the transom). I'd wager that with the lower weight and economy of the current crop of 4-stroke / Dfi 2-stroke outboards, it would be just as economical as the diesel too.
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Old 12-15-2011, 09:39 PM
savagescout savagescout is offline
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Yes i have picked up a diesel for a bargain price and like the reliability and lower centre of gravity that it will have to offer. I wanted to determine whether a jackshaft system is something that can be made up or can you only do an off the shelf type system?

Cheers,

Nick
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Old 12-16-2011, 06:17 PM
powerabout powerabout is offline
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You can make some of it but buy the support bearing assembly that mounts to the transom bracket at least.
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