Repower question

[damagemas]

New to the site, my question is has anybody ever heard of someone using an marine generator as an means of power? Can you take the alternator off and modify so it will accept a gear box? My problem is that my 27 sailboat does not have an engine and it is difficult to find on on my budget but i do have an older single cylinder marine Onan that is not being used. have anyone evere heard of this being done?

[lans0012]

That is an interesting question, I'm curious to what the knowlagable people have to say.

If it were I in the same position, I would Craigslist the generator or barter it at a local engine shop for something that would work better. An running Onan generator should be worth something.

[overbored]

is it water cooled? most smaller Owan's are air cooled and most boats use water cooling. A 27' boat can use an outboard. an outboard will cost mush less then the prop and propshaft for an inboard.

[Barquito]

If your boat has overhang on the stern, OB is not ideal.

[Faster]

The type of boat will make a difference, as will the cooling as mentioned above. Even if you can live with an aircooled engine there's always the exhaust to consider..

Also, what equipment do you have? Is there already a shaft/strut/gland? What mounts can you manage to make? Engine beds in place already? If none of this is there then there's a lot of work and details to sort out.

Chances are you'll end up with something that is so 'non standard' it may become problematic down the road on a number of fronts.

However if you're handy and have access to fabrication equipment it might be a fun project.

While it's difficult to justify the cost of 'marine' engines, there is a fair amount of engineering required to make it all work - most of which is not the engine itself, of course, but the peripherals.

[Barquito]

Probably more complicated and $$$, but, what about just using the generator to do what is is supposed to do, produce electricity. Then run a high torque electric motor off of the electricity produced.

[damagemas]

The generator is water cooled and the stern is overhung. The boat is set up for an inboard already. However my first plan was to run a 36vdc electric motor with a battery bank with the generator to charge the batts. But my electric motor is A 2.0kw which is about 3hp my guess is a bit small.

[CalebD]

Many older sailboats had Atomic 4 gasoline engines in them. If we knew the year and model of your 27' sailboat we might be able to figure out if this was the case. In any event it is likely it had an Atomic 4 at one point.
A ~ 3HP electric motor pushing a 5000 - 7000# boat (again, it depends on the make and model) will work to a point but be nearly useless if wind and waves kick up.
In my not so humble opinion, installing a re-built Atomic 4 would be the cheapest and most cost effective way to get you propulsion that you could use even in a blow. Used Atomic 4's are often listed on Craigslist and other places for around $1K - usually in working condition. Of course, buying a used engine is only half the battle as the installation process is not like flipping a switch.
I wont advocate using an outboard on a boat with an overhang even though it might be easier to install.
It would really help the brain trust here, such as it is, if we knew what Make/Model and year 27' sailboat you have.

[damagemas]

It is a 1979 Dockrell

[Faster]

In case you were all wondering:

DOCKRELL 27 sailboat on sailboatdata.com