4.3 mercruiser - 16 foot mahogany runabout

[Sasquatch1]

im building a 16 foot mahogany runabout that is a new design. It has a 23 degree deadrise and is desighned for a sterndrive I/O. My plan was to plant a rebuilt 4.3 mercruiser and an alpha one drive for power. i dont have any experience with the 4.3 but i figured it would have enough oomph to get that much hull up and out of the water . any input or words of advice from anyone would be helpfull.
thank you

 

[Bigkat650]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Welcome to the boards Sasquatch!!


Sounds like you got a fun little project ahead of you, can't wait to see how it comes along!

As far as the 4.3, that should give plenty of power to get a 16ft runabout moving along well, even a heavier wooden boat. Just make sure you get the right prop on it, and it should fly!! I'm, sure you will get plenty of good help around here on your build, and the engine sub-pages may be able to get you a few more technical questions answered on your motor and I/O setup.

Good Luck!!

 

[oops!]

Re: 4.3 mercruiser - 16 foot mahogany runabout

hi....welcome to iboats !

cool project.

a v6 in a 16 footer?.....yoo are going to have to add a heat sheild for re-entry !

is this a racing boat?

 

[Bamaman1]

Re: 4.3 mercruiser - 16 foot mahogany runabout

If you have no experience with I/O's, I would suggest you buy a used boat with a 4.3, and transplant the parts to the new boat. To purchase a used engine and used outdrive is just the start of a bunch of expensive parts, wiring harnesses, gauges, controls, steering, bilge pumps, ventilator fan. It goes on and on.

Let me warn you that just getting the bellows' sealed is not easy for a neophyte. You want to get it right, or you'll get water into the U joints, etc.

I have a 17' deep v bowrider with the old 470 engine. It's actually better to have a little longer boat for these powerplants are very heavy. And, the 4.3 motor is heavier than my big strait 4 engine. On shorter boats, I prefer modern outboards.

 

[Pmccraney]

As above guys said, your dead rise won't slow you down.. You may already know this, but Merc I/o set-up requires very specific transom dimensions...2- 2.25 inches thick, 10-16 degrees angle, dead on the balls flat and parallel...so just make sure you factor all that in..

 

[Sasquatch1]

Re: 4.3 mercruiser - 16 foot mahogany runabout

No i dont believe its gonna be a racing boat.. just something nice to put around in (and by put i mean skip across the top of the water ) the plans lay out the blocks for a 4.3 plant which is the only reason i was leaning towards it. id rather stay away from an outboard cause i want to stay with the closed transom barrelback look.. Im not too worried about making sure everything is sealed, im planning on doing prety close to a full rebuild pending on what i get ahold of for a parts boat. I could probly retrofit the blocks to accomodate the 4 cylinder.. which would cut alot of weght as well... any thoughts there?

http://www.classicwoodenboatplans.com/deep-v-16-inboard/
heres the desighn
Thanks

 

[boatnut74]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Looks like a neat project! A 4.3 should make that hop, skip and jump across the water

 

[glnbnz]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Yes this looks very interesting. Please keep us informed on how it is going!!!

 

[jasoutside]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Subscribed!@

Some day, when I am an old fart, kiddos are grown and gone, I would love to do what you are doing.

Please post up often on your build progress

 

[Sasquatch1]

Re: 4.3 mercruiser - 16 foot mahogany runabout

I rebuilt a 16 foot mahogany plywood boat allready.. it was my grandfathers. a whirlwind. all i can say is i caught the bug and i cant stop i love woodworking and im allways lookin for something new to do

http://www.flickr.com/groups/1402629@N23/pool/

the pictures under the name dave894 and dave1099 are of the boat i rebuilt

 

[oops!]

Re: 4.3 mercruiser - 16 foot mahogany runabout

if the plans call for a 4.3 ...go for it !

woodies can be built quite quick.....

a doner boat is a great idea for you......if you piece meal the motor and drive parts you will go bankrupt

 

[MichaelP]

Re: 4.3 mercruiser - 16 foot mahogany runabout

I always wanted to build a 22' wooden cruiser, even collected a bunch of plans that I still have. Now that I'm building a new garage my wheels are turning on that project again. Nice job!

 

[Sasquatch1]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Thats basically what happened with me.. i finished restoring my whirlwind, a bay is open and unused in the machine shed and i need another project haha

 

[Tahorover]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Welcome to the boards Sasquatch!!


Sounds like you got a fun little project ahead of you, can't wait to see how it comes along!

As far as the 4.3, that should give plenty of power to get a 16ft runabout moving along well, even a heavier wooden boat. Just make sure you get the right prop on it, and it should fly!! I'm, sure you will get plenty of good help around here on your build, and the engine sub-pages may be able to get you a few more technical questions answered on your motor and I/O setup.



Good Luck!!

Wood boats weigh less than fiberglass.

 

[Bigkat650]

Re: 4.3 mercruiser - 16 foot mahogany runabout

Wood boats weigh less than fiberglass.

Well my experience is with aluminum, and I'm only guessing--but I assume it outweighs a tin boat

 

[Sasquatch1]

Re: 4.3 mercruiser - 16 foot mahogany runabout

It depends on the type of construction your dealing with on a wooden boat. My 16 foot molded plywood boat is light enough for me and my father to lift :facepalm: (although were equivelant to a pair of oxen :redface: ) a lapstrake boat is one of the heaviest things ive ever seen, and mahogany plank isnt much better haha. I believe this construction will bring about a boat of moderate weight, probobly a little bit lighter than that of a similar glass boat. im planning on overbuilding a bit. i allways seem to anyways

 

[Donzi boat]

Re: 4.3 mercruiser - 16 foot mahogany runabout

How is your project going? I'm building the very same boat. It's almost done. Here are a few (unfinished) pictures.