small twin OB's

[xort]

There are plenty of large twin outboard rigs around.
How about rigging 2 6 hp OB's to a small boat?

Two small engines are easier to lift on & off than one large one. There would be redundancy with 2 units and the ability to run on one when that's all that is needed.
Rigging the two tillers together would be fairly easy but how to combine 2 throttles? Any ideas?
Thanks

 

[tashasdaddy]

Re: small twin OB's

thats where the problem comes in, there have been all kind of theories. but no solution. i say mount the far enough apart you can sit between them, one for each hand. but the really need to be sinked.

 

[JB]

Re: small twin OB's

The weight, fuel usage, drag, cost and maintenance would be a LOT more than a single 15.

Dual controls seem the only realistic way to try to synch the throttles. That means remote control. More complexity.

Some advantages, yes, like those you mention, but they are trivial compared to the disadvantages.

 

[Dhadley]

Re: small twin OB's

There's only one reason for having twin outboards -- not enough room for 3.

 

[bassboy1]

Re: small twin OB's

What JB said is true. But, if you like a good project this would be it. You could connect the steering arms to one tiller real easily. Then, you could have a separate throttle control. Or, if you are failry tecnically advanced you could use heim joints and ball joints to make a twist throttle in the handle. Or, you could have three and make only one steerable and the other two fixed. You could have fun w/ this project.

 

[Texasmark]

Re: small twin OB's

Now D, man, you're gonna have to explain that one. d

I remember when I was in high school run by a bunch of religious brothers (like nuns, but men). They had a 15' molded plywood boat and had rigged 2 Green/silver Mercs to it (permanently, not for daily removal). I think they were 10 hp. Looked pretty cool. That was back in the days of the slide throttle with the lever going left to right across the front of the cowling. You had to advance the throttles together to keep one from kicking up so I guess one brother held on to the tiller handle while another grabbed the gas(es) and away they went. d

Mark

 

[steelespike]

Re: small twin OB's

This does sound like fun and it might be relatively simple.
Tie the 2 together with some sort of simple bar.
Go under the cowl and rig a control cable something like a lawn mower throttle cable from the throttle of one motor to the other.Done right you might control the throttle from either motor twist grip.Shifting might be tricky but you might be able to put one in neutral and control foward and reverse with one motor only.
I saw a picture of a big launch in some 3rd world country.It had 2 Honda 50s apparently hooked together and the driver appeared to be standing leaning against one and controlling a throttle and tiller with each hand.

 

[Texasmark]

Re: small twin OB's

For the record.

Once I saw a guy with a 15 hp and a 25 hp Rude on a boat; back when rudes were pale blue and had the rounded covers. Don't know if he had twist grip throttle or slide type. Not sure how he was doing what as I was a teenager and had my mind on other things and I was 20ish yards away awaiting my turn to load onto the trailer to leave the lake.

But anyway, I remember seeing him planeing off as he left the dock and he was at the rear of the boat with his hands on the engines and the 15 hp kicked up out of the water to his apparent amazement as he was scrambling to fix whatever he must have thought was causing it. I was of the impression that this was his maiden voyage with this setup.

Now, did he throttle up the 25 and not the 15, was the thrust of the 25 superior to the 15 to the point where the 15's lower unit was a drag element or what, I don't know.

So, if you are gonna run 2, looks like you need to keep the thrust equal or the weaker will (should, might) come out of the water.

Mark

 

[xtraham]

Re: small twin OB's

There's only one reason for having twin outboards -- not enough room for 3.

 

[cobra 3.0]

Re: small twin OB's

I dunno. I had hooked up two little outboards a 3 1/2hp and a 5 hp non twist grip throttle engines. My 7 1/2 hp Merc. at the time, still flew past as if it was parked...probably because it didn't have the power to plane and the wrong pitch props to help do it.

I can see it for bigger outboards, but a real PAIN for the size of outboards you are referring to. A little 15hp would still fly past your two 6hps.

 

[Texasmark]

Re: small twin OB's

xtraham man oh man, what is that a drug peddler chase boat? Geez when you hammer those babies I bet the transom really groans

Nice pic.

Mark

 

[xtraham]

Re: small twin OB's

xtraham man oh man, what is that a drug peddler chase boat? Geez when you hammer those babies I bet the transom really groans

Nice pic.

Mark

thats a pic of a one of a local boat builder's boat...
I drove by his place the other day and he had about a 45 footer setting outside with 5 outboards on the stern..........

 

[tashasdaddy]

Re: small twin OB's

here's a link to the guy in the merc forum, running 2 25 hp with a common tiller;

http://forums.iboats.com/bbBoard.cgi?a=viewthread;fid=29;gtid=1222097

 

[v12mac]

Re: small twin OB's

This is a guy on Naples bay, 4 275's on a Yellowfin. I'd like to see the the first guy to repower a 70' Hatteras with 7 or so outboards!