Hypothetically Speaking

WoundUpMarine

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xbskt

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13 Whaler, 14 Salty Boats, 28 Crowley Beal, 36 Northern Bay. WTF!?!
How much does the Volvo weigh?
 

xbskt

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13 Whaler, 14 Salty Boats, 28 Crowley Beal, 36 Northern Bay. WTF!?!

WoundUpMarine

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chortle

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Hypothetically speaking, what's the thought of dropping a 42p, 240hp Volvo in my 23 seaway? Right now it has a 55hp Perkins, unknown gear ratio(definitely not 1:1 though) and a 14x10 prop and makes about 12knots. There was never a tachometer on the boat so I have no idea what the engine was turning to make that speed. I'm picking up a 1:1 ratio 72C BW gear for the project. Plan would be to use a 1.25 shaft, and a 15x? wheel, the Volvo spins up to 4200. The prop aperture is 18 inches and I'm fine with the clearances. What size wheel would I need? Boatdiesel prop calculator says a 15x15 wheel, but I'm not sure, should be easy to find one to test it out.
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Sounds like fun but I would keep looking for a lightweight Yanmar, might be more zoom.
 
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Ok, first, to me, it's a cool idea. Second, run what you brung. Yeah, Yanmar is OK but if there's a Volvo around use it, it's not like they're no good. The tach thing, $50 Stinger. Worth every penny and you'll use it before and after the project. Check crank and shaft speed. As for prop calculator, I gave up on it. Ran 2 boats through 4 different engineering spreadsheets and they all overwheeled the shit out of them. I would borrow any wheel i could and go from there. Shitty old Bronze can be repitched 2 inches and if you like the boat enough you can treat her to NiBral after a few seasons.
As for pushing the weight aft, I'm all for it. But I own a JC, if the weight isn't aft the boat decides where you're going, not you.
 
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Diesel Jerry

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the_Bartender

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I see you have an engine waiting, @WoundUpMarine , but I thought I would throw these out there in case someone is looking. I do not have any affiliation with these engines.


 

samhop

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If you can get enough wheel on it and the gear will take the power why not. you know what i think its a good idea even if you have to go new shaft, gear, wheel, drop the skeg and move the engine bed for weight.
 

PatriciaLynn

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Rebuild one of those 305's with a stroker cam. In fact, I should have done that.
 
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