Conversion and Restoration OMC Stringer to Whatever

[TruckDrivingFool]

I think that's gonna take some work to hang an OB

I'd stick with the I/O repower

 

[RiverNoob]

Of course I'm jumpin, you always want to keep an open mind and explore all options.
jet drive sounds cool, but I usually see those on flat bottoms.

What about this;
How about an I/O repower using 2 merc 120 or 140 setups,
I've seen offshore boats like that before.

I could set them up with two ignitions and two tandem throttles to move, start them both and move the throttles simultaneously to cruise, start one and run it low to troll slowly. Also if one failed, there would still be another strong enough to push the boat back into dock if I am out away from shore.

Does that sound like a good idea for a system?

 

[Scott Danforth]

your hull shape lends itself to a single outdrive.

in my mind, you are way overthinking this.

rebuild the whole transom (and associated stringers, bulkhead and floor), cut-out for a mercruiser or volvo (now the same hole) install drive and motor, hang kicker, buy towing insurance, go boating.

by the looks of your transom, the OMC leg hung down way too low and the boat was probably a pig in the water and sucked in shallow water. so anything you put on the back of it will move it as well as the OMC leg

 

[RiverNoob]

Yep,
Your right. All these other options are going to get to risky. And the bracket type that I would need is way more expensive than others to buy.

I'll just circle back to the original plan. New i/o, and kicker.

I got my respirator and tyvek suits. My filters for the respirator haven't come yet..

If I get those by this weekend I am goin to cut the deck out and inspect stringers and other areas, will post new pics.
When I get to transom and stringer re-building.. Does my trailer with rollers look supportive enough?

 

[Guest]

After seeing the pix of your boat, Noob, you really made a great choice for the water you intend to boat on. She has abundant freeboard and a nice deep vee hull.

Now let me address some of the options you're considering:

A jet drive would ensue not only require you to re-fab the transom, it also cutting a hole on the bottom (!) of your boat for the suction intake. you would also have to move the inboard engine forward in the cockpit to accommodate the shaft coupling. Jets are great for shallow water but not the best choice for running an "active" inlet like the Columbia bar. I have built and run many jet boats in my profession and they offer sloppy handling at low speeds, no steering at all if they loose power and you don't get the full power of the engine in the water like a conventional propeller. This is why jet outboards are rated at "less power" than their propeller driven counterparts.

Surface drives are nice, but I can tell you, the sticker shock alone for one these rigs will turn you off. You also have complex hydraulic rams outside the boat involved for steering and trim, and trolling for fishing would be damn near impossible. They are not intended for that.

Yes, you could successfully notch the transom and install an outboard, but since your hull is so deep and offers generous freeboard, a bracket may be your best bet. You can retain the closed transom while using an Outboard and get the benefit of all that freeboard your boat offers in the stern. Even so, a dry motorwell could also be fabricated and give you the same effect if you go with a conventional notched transom..

But again, I advise you to buy a pre-formed bracket and build the transom to suit.-. Typically the 3" thickness. You will need an outboard with a 25" shaft length (30" for your particular hull would be better if you could find one.)

As for a sterndrive, after seeing your boat, that would be my choice. Its difficult to fond a boat like yours with such generous high sides. It would be counterproductive not to use it.

Twin I/O's would be good too, but first you must ascertain if the hull you have has the sufficient internal structure to handle it. You may be biting off more than you can chew in both time in money on this option.

 

[RiverNoob]

Ok,
these other ideas are all pretty risky, more expensive, and bad, I agree. I just wanted to check out all the possibles. Obviously the best way to go is just what everyone said originally,
I need a Mercruiser alpha gen 2 with a 5.7L 350 setup in here. So that?s what I will look for.
I put all my other stuff up for sale. Kind of a shame cuz the GM 305 runs like its brand new, but oh well.

Meantime, I gutted through the entire deck and ran into something puzzling. There are no wood stringers in this boat. at least I don't see any. The 3-4 foot wood beams that the motor was on, end at the forward wall of the doghouse. There are no other wood beams in the bottom of the hull anywhere.

See new updated pics of the weekend job here:
http://s952.photobucket.com/user/RiverNoob/library/Columbian 2
So,, it appears that the boat just had storage/fish wells in the deck and these are glassed boxes basically that go all the way to the hull,, the fuel tank also sat against the hull,, with the deck on top and the whole thing was foamed. So there aren?t any stringers in there at all. It just goes straight to the laminate from the topside of the hull ribs going through the deep vee.

So I still want to raise the deck for about 4 feet at the point where the windshield is to a little past where the console currently is, and move the cockpit to the center of the raised deck, put walk-around sides up to the bow so you can get there without going through the hatch, and extend the space where the cuddy is back--- about 4-4.5 feet of extra area under there. I could put rib walls going all the way up from the hull to support the new deck part.

What I wondering,, so now when I re-do the transom, should I put wood beams running up the hull from the transom where there weren?t any before? It?s strange, one would think the foam must have been there to support the hull underneath the deck,, but the foam didn?t quite go all the way to the hull,, there was a void under there through most of it between the hull and foam where water could drain down to the doghouse.
Is this boat just designed to be sturdy enough without stringers? I don?t see how that could be.

Anyone have insights?

 

[jbcurt00]

Can you post larger MB pix to your PB acct. I cant seem to enlarge them enough to see detail and not have the pix go blurry

 

[RiverNoob]

Well I copied them off my phone. so if I zoomed in closer with my phone that would help I think.

Which particular area are you trying to see?

 

[RiverNoob]

Well this string really died down with enthusiasm,
Anyway, I got this book, Boat Strength, by Dave Gerr, came highly recommended. Going to use to create a little schematic for rebuilding the deck after the transom is re-built with a good solid structure, it seems pretty easy to understand.

I don't know if I'm going to find a donor boat that I will be able to use, however, my brother has an extra chevy 350 5.7L with Vortec heads in in his garage. totally rebuilt.
I should be able to just piece together the necessary marine parts and fit that engine to a merc alpha gen 2, correct.

I found a couple sources for getting a complete Transom assembly for a merc gen 2.

My question at this point is,, can I just get the transom assembly and build my transom up, cut the whole and put the assembly in, and then get the marine motor parts to mount the motor in later? or do I need to have the whole thing to build around before-hand?

I have to take a hiatus and this point, since hunting season has started, its bird hunting season now, deer and elk after that. So I won't get back to the boat til early November. I would like to move fast at that point though, and have it ready for spring salmon runs.
So any input would be helpful

Thank you,

 

[Willyclay]

Not familiar with the Gerr book but maybe other members are and can comment. Member Zool's post #15 identified the critical dimension of transom thickness for Mercruiser's as 2-2.25inches, min-max. The link below is from the wealth of info left in the forum by member & guru Don S., RIP, and may help you with the next step of your project. Be safe during hunting season and we look forward to your next thread update!

https://mercurymarine-gsdesign1.net...27-b6c0-5366cc9f4b8b/alphagenii_1992-2001.pdf

 

[Bondo]

I should be able to just piece together the necessary marine parts and fit that engine to a merc alpha gen 2, correct.

Ayuh,.... You can do that, but yer budget will double or triple,.....

 

[RiverNoob]

Bondo,,
You mean my budget will double or triple putting the stuff on this 350 I got,, as opposed to just buying a used 350 with everything on it?

Or you mean as opposed to buying a donor boat?
I'm not really seeing donor boats in the motor setup I want. There seems to be a lot of them in other markets. Like Florida.

 

[Bondo]

Bondo,,
You mean my budget will double or triple putting the stuff on this 350 I got,, as opposed to just buying a used 350 with everything on it?

Or you mean as opposed to buying a donor boat?

Ayuh,..... Either, Or,.... Dressin' a motor, piece by piece,... Carb, over $300....
Ignition, another over $300,...
Manifolds, etc.....

It's all the little tiny pieces, 'n bits that add up quickly,.....

Rotten boats will become more plentiful the closer the winter lay-up season approaches, as folks don't wanta store junk,.....

 

[RiverNoob]

I see what you mean,
I have seen motors on there fairly routinely with all the extras, but which have a cracked block, no compression in a cylinder, etc, something like that.
They are often listed for 1000-1200. People don't like to work and pull things apart just to sell them,

I could prolly talk one of those guys down to 800-900 and get it to pull all the stuff off. but since I'm on a hunting season hiatus right now,
I will just keep an eye out for donor boats until I'm actually ready to go back to work on it.

Thanks,

 

[Bondo]

Ayuh,.... I only paid $500. for the year old 4.3LX on the shippin' crate the new bobtail Merc came on,....

another $100. for a fresh tanked, cleaned, plate honed 'n mic'ed at factory spec's replacement block at a local machine shop,....

I gambled on the manifolds, welded 'em up, 'n got several years outa the set up,....
As I learned alot more 'bout boats here at iboats, I finally replaced the manifolds,....
over 15 years, 'n nearly 2000 hours, 'n still runs rock solid,.....

 

[RiverNoob]

$100? You got a 4.3 reman replacement block all shiny and rebuilt for 100 dollars?
am I reading that right?

I've never seen anywhere that had nice rebuilt ones for less than 1200 or so for a 350. I wasn't lookin at 4.3's but I think they were usually still in the 900-1000 range.

maybe I can find some hot deals like that for my setup over the winter.

 

[RiverNoob]

Well also,
since you sound like a veteran negotiator of hot deals, let me know if you see anything in the setup I want.
that would be a help.

I pretty much just watch craigslist, ebay, and copart auctions. you know better places to look?

 

[Scott Danforth]

Keep your eyes open and be prepared to deal. Deals come up and disappear quickly. Also drive around. Hard to believe, but the best deals are probably sitting at the end of someone's drive and only advertised with a hand written sign

 

[Bondo]

$100? You got a 4.3 reman replacement block all shiny and rebuilt for 100 dollars?
am I reading that right?

Ayuh,.... The Bare block,.... the cast iron castin', complete with bearin' caps, honed, 'n mic'ed to spec,....

Loaded the guts outa the cracked block into it,....
Fresh rings, bearin's, 'n gaskets of course,...
Dressed it with the dressin's off the cracked block,.....
Bobtail motor to bobtail motor, only change the Bare block,....

 

[Guest]

Noob:

Bondo's right, Parting up a sterndrive is a fool's errand, I tried doing this when I was going to restore my (sterndrive) center console (that I later went with an OB). And I had the basic 5.7 motor and the gimbal and drive, but even then, when you add up all the marine parts it gets expensive fast. (intake manifold, carb, flywheel,exhaust, pumps, etc) I spent a fortune on all that stuff and had more to go, so I sold it all and went with an outboard. Its much easier to buy the sterndrive engine and unit pre-assembled, because you now have a "base" unit you can work off of. If you're near freshwater areas like lakes or rivers, etc. they are the best places to find used inboard and sterndrive parts because you don't have to deal with the corrosion. One other thing, if you can afford it, put a freshwater cooler on it, even a block only system. It pays big dividends with saltwater use. JMHO