30' Tollycraft Outboard Conversion

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I appreciate your concern but its what I want. Faster, more efficient, ease of maintenance, 5 years of warranty. When I say the internals are good I mean the rotating assembly. But they are still 32 years old and rusty as hell from the previous owner. Due to the rust I am constantly having mechanical issues with every component but the internals. The only way to get ahead of it all is to get it all out and start new. And then I still have the old technology so I will still have about 1 NMPG or less.


They do these conversions in Florida a lot from what I see. I just can't find a Tolly that's been done. But boats of similar weight and hull type and size seem to pick up quite a bit of speed at slightly less fuel burn then inboards.

Boat people have this perverse thought of always worrying about resale. But yet often the same people who talk about it will spend huge money on old cars, booze, other little toys and trinkets that have little or no resale at all. Seriously guys in town I talk about this have blown well over $100,000 in the last few years on junk they'll never be able to sell but when it comes to their boat they stress over the price of new fenders.

I'm just looking to see if anyone has done an outboard conversion not to argue the point of doing it.


Robo,


I'd say good on ya, and have at it. This is not an investment, it's an expense and that's what toys are. If it were short term (like a one time loop trip), there could be an arguement to have a boat that is popular and sells fast, but few make money buying and selling.


If you come close to your projected costs, I'd say it's a BARGAIN, and you'll have MUCH more reliability and performance.


There's not a huge demand for old gas powered boats, so if you like the hull and convert, it's more than likely MUCH less costly than selling and buying something newer.


As for keeping the old engines and upgrading them... TOTALLY agree with you. It won't be a few thousand, it will be well north of your conversion costs and you'd still have old gas engines. I've been there!


As for balance, you can easily figure out how much the center of gravity will move, just like they do in aircraft conversions.



I've had a few friends do conversions.. IO to OB, and gas to diesel. None of them will make money on the deals, but every one of them ended up with better performance and reliability on a known hull that they liked.



So.... go for it!
 
Thanks bud! Pretty excited. Hoping the bracket will be started soon and I can gut the boat this winter.
 
That sounds like a fun project and with your access to the outboards it seems like you're in the right place at the right time. I'd look at doing a hull extension like that Pompano to increase buoyancy aft rather than metal brackets. I wouldn't think it'd be too hard to figure out about where the CG of your boat is now and then figure out where it'd end up with the new motors. Also not hard to figure out how much buoyancy you'd get from the extension.
 
That big hole in the aft deck where the old V8s were will make for some great new storage areas. If ballast is needed it can go right there too.
I looked at buying a Tolly 30 like yours but decided to go bigger. I really liked the design and functionality of the Tolly. A lot of boat in 30’.
My guess is that even a slow speeds (6-8) knots it will get better mileage there too.
Sounds like a great project for you since it will be your last boat, you should have exactly what you want. Go for it!
The only downside to a bracket or pod boat that I have experienced is that the engines throw up a lot of water due to the ride plate not always being in the right spot. This is where a full hull extension may be an advantage.
 
This is the future of boats. Outboards that have capitalized on the advances in car engines have become much more reliable, powerful & fuel efficient while getting lighter at the same time. And not only does converting to outboards get the noise & vibration out of the boat but it frees up a huge area for storage. And the biggest plus is how much safer the boat will be. In my opinion you will greatly increase the value of the boat.
 
Robo, have u considered insurance angle? Be sure you can insure what u end up with. Sounds like a great project.
 
Please keep us posted on your progress. Very interesting conversion. I'm curious why you went with a local builder instead of Armstrong?
 
I love outboards.
And putting them on the transom is not ideal because of the weight far aft. But a boat designed for an OB has advantages that are designed in.
David’s Pompano is a conversion. Done at the factory and modified by a NA (I assume) the stern extension can be very acceptable. But it’s not ideal.
Balance of weight and flotation isn’t all there is to it. If you compare an IO boat w a straight inboard boat almost all ways the inbd boat is better. Airplanes have the same issues but may be more sensitive to variations.
There is a huge difference between a boat w her weight centered amidships and one w the weight at either end. At either end in head seas there could even be a structural problem but I’m talking about handling. The boat w weight at the ends will be sort-of a slug yawing and pitching. It will feel more barge like than one w weight amidships. Turning sharply is obvious but it will prevail even w small course changes. Pitching actually IMO is best w the weight in-between at either end or amidships. And the basic shapes of hulls dictates various variations in weight distribution. Many inboard boats have fuel tanks aft. They were put there for a reason but it’s not ideal to have non-fixed loads at the ends of a boat.

Re the above one can see weight distribution in small craft is not simple.

But the best OB extension is as David has except extending the whole hull. Almost always the full hull extension is best and all else is a compromise. Just plain bracket OB extensions are bad to undesirable to unsafe IMO.

But re David’s boat what are the downsides to doing a full hull extension instead of the add-on? It’s kinda like synthetic oil. Just money.
 
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We have a 1989 Bayliner 2958 that we are considering doing the same. This one has outdrives that need replaced also. I have spent close to 30 years in heavy equipment repair and I'm not going to spend my golden years trying to squeeze in between two car motors stuffed into a 10.5" beam to do repairs & maintenance.
Their are miles of 30+ year old dock queens sitting with non running or Ill running car engines in their belly's. 30 years ago builders had little choice for power plants, look at the new boating magazines, many new 30'ish boats with outboards.
Your project is awesome & looking forward to seeing the results.
Here is the bracket we are looking at. http://http://www.dusky.com/parts/outboard-brackets
 
"capitalized on the advances in car engines have become much more reliable, powerful & fuel efficient"

What would worry me is the difference in cruising HP between a car and a boat.

Sure tiny car engines with turbos can be rated at 250-300HP , for great 0-60 times , but a vessel might need 150HP for hours on end.

It will be interesting to see weather these marinized engines can operate at 10-15GPH over the long run.
 
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