Gearbox

[cookiesa]

I may have missed it but under DIY Marinizing I think it would be good to have a thread on how I transferred the power from my Isuzu or whatever to the prop. No doubt some rather ingenious methods and adaptations have taken place.....

Anyone?

[TerryKing]

cookiesa, it would be nice to collect a gallery of possibilities in the Wiki.

I'm working on an idea using a typical transverse engine with it's transaxle, as in a typical Front-wheel-drive car. I've got to clean it up, but I'll post it as a subject on DIY Marinizing.

[cookiesa]

OK call me old (I'm not!) but what exactly is a wiki I see they are appearing on all sorts of forums and I gather it is more or less like a listing

[TerryKing]

OK call me old (I'm not!) but what exactly is a wiki

OK call me Young (I'm Not) but I just started doing the Wiki stuff this year...

The Boat Design Wiki (You can click on it way up on the top of every page) is supposed to be a place where We-All collect all this good stuff we figure out while discussing things here on the Forums, and put it in one place (per subject) so it's easy to find. It's even pretty easy to have a Table Of Contents at the top..

Any member of BoatDesign.net can EDIT and add stuff to the Wiki. So you can just jump in and add a couple lines when you have time..

[cookiesa]

Thanks! Now I understand what the heck it is all about! Does WIKI stand for anything or just something that has caught on???

[TerryKing]

It's old Hawaiian for "Quick", apparently often used as "Wiki Wiki" .

[cookiesa]

Well I guess everyone just buys a marine gearbox then!

[TerryKing]

Most use Marine Gearboxes, at least in larger 'professional' boats.

Only others I've heard of:


- Automotive like Chevy/GM Powerglide, mostly in Ski / Drag boats
- Modified Automotive manual transmissions, with added thrust bearing, higher reverse ratio (Stokes Marine USED to make these)
- Unmodified Auto engines/transmissions: mostly on Lobster boats, 3rd world countries. I once had a ride in a Prince Edward Island lobster boat with a straight 8 Buick with Dynaflo tranmission and straight-up exhaust. It was fast!
- Direct 'jackshaft' to surface drive system with stop/reverse 'vanes'


And, Maybe, my current idea: Complete front-wheel-drive engine and transaxle with jackshaft to external thrust bearing..

Anyone else??

[Elie]

If the propeller pitch cannot be ajusted, then I wonder what is the real purpose of have multiple ratio transmission on boat. However, I just purchased an Autoprop (Brunton automatic variable propeller pîtch http://www.autoprop.com/ ). This strange beast is said to have the ability to indefinitly adjust its pitch or more precisely the incidence angle of the leading hedge of blades depending essentialy on the rotational speed of the prop et the speed of the flow of water on it. I imagine in that situation a 2 or 3 ratio transmission would increase the efficacity of the propulsion in most conditions.

[cookiesa]

Good point.

For most I think the use of a multiple ratio is more to do with how they get around adding reverse, the additional ratios are more because of using an automotive trans or similar.

That is a bit of what led me to this thread. Just wondering if someone has come up with a way of getting forward, neutral and reverse (astern) without using an automotive or marine gearbox?

Doesn't seem like anyone has found a way yet though?

[TerryKing]

That is a bit of what led me to this thread. Just wondering if someone has come up with a way of getting forward, neutral and reverse (astern) without using an automotive or marine gearbox?

The only other ways I've heard of are:


Vee Drive unit with built-in neutral and reverse gears (I have a Casale)
One of the 'outdrive' or 'sail drive' units that have gears that mesh for forward and others for reverse.
Hydraulic Drive where the engine runs hydraulic pump and fwd/reverse is done with valves
Some big 'outdrive configuration' drives can be rotated 360 degrees for reverse (like a small outboard)
OR, the old Steamboats that stopped the engines and ran them in the reverse direction by switching the valve arrangement.


Maybe a huge 2-cycle Diesel can be run in reverse rotation?

[Elie]

I have a very inventive and capable friend that devised an hydraulic drive for its copy of Slocum's Spray steel sailboat steel. A diesel 4 cyl engine drives a big hydraulic pump. In turn this pump dirve two hydraulic reversible motors each coupled to an saidrive of his conception and construction. So, no transmission just a direct drive for its 'engines'. Reversing engine does the work of the tranmission. Bu he has to be carefull since reversing can be done almost at any speed and torque and can damage the gears of the saidrive. The other problem is thas hydraulic drive implies a certain amount of perfomance loss. But it works, and is a model of elegant simplicity!.

[TerryKing]

A diesel 4 cyl engine drives a big hydraulic pump. In turn this pump drives two hydraulic reversible motors each coupled to an saildrive of his conception and construction. So, no transmission just a direct drive for its 'engines'. .

Elie, that's another, for sure! I added it to my 'list'.

I will be back 'home' from Africa to Vermont, just South of you, in a couple of weeks... I'll get my old boat running on Lake Champlain pretty soon thereafter.

[Elie]

Hi, Terry, Strange world!. My sailboat passes its winters at Rouses Point NY., my summer marina is at the tip of Isle La Motte Vt, I sail Lake Champlain, and the boat I refered to was plying Lake Champlain and you may have seen it! Regards.

[TerryKing]

Hi, Terry, Strange world!. My sailboat passes its winters at Rouses Point NY., my summer marina is at the tip of Isle La Motte Vt, I sail Lake Champlain, and the boat I refered to was plying Lake Champlain and you may have seen it! Regards.

Elie, I'd really like to see that boat and it's drive system some time; I'll check in when I'm back on the water! I have a big Vickers pump waiting for something important to do...

My boat looks JUST like that one in my Sig. My GrandDaughter is sometimes doing Quebecois Fiddle Tunes and clogging on the roof like in the photo. But not underway! That photo was taken at Valcour Island, one of my favorite places. The boat has been up the Chambly Canal / St. Laurence to Montreal a couple of times.

Mon Francaise 'cest non tres bon, mai Je attempt...