high powered twin engine inflatable!!!

[melandnick]

I know you are all probably going to shoot me down in flames but...
My ideal back up tender ( that I can dive from ) would be a 2.7m or so inflatable with 6-8hp of outboard.
Problem is that I don’t want to carry a motor of that weight so I have an idea.
My current out board is a 3.5hp mariner and I have a second as a back up.
Is there any reason that I can’t fit them side by side on the transom of an inflatable to give me the power I want?
Assuming of course that there is room for them to turn and fit side by side etc?

Nick

 

[SailBobSquarePants]

Valuable...

if you have a 3.5hp two stroke Mariner, they are like hen's teeth if in good shape. They are lighter than the newer 4 strokes, and should command a nice used price.

Why not sell one on, and then pick up a new fourstroke 6HP for a main engine, and keep one 3.5 Mariner as a backup? If you can strike a good deal with someone who knows the value of the Mariner 2 stroke (someone who wants to transom mount it as an aux for a racing boat), you may not be out of pocket that much...

 

[melandnick]

Good advice, I know ( and I actually have 3 not 2 but I will only take 2 when we go cruising )
In fact to clarify, I have a tohatsu 3.5, a mariner 2.5 and a mercury 2.5 but both of the 2.5 motors have had the carb mod done so they are all now 3.5hp.
Problem is the weight, I really don’t want a heavy outboard hanging from the pushpit and don’t want the problems of trying to get it into and out of the dinghy.
Also, my main tender will be a nutshell hard dinghy and I will only want a small outboard on that.
So I am looking for a solution for when I want to go for a swim to catch some dinner and can be bothered to blow up the inflatable instead.

Hope this makes sense and I agree with how good these little engines are.

 

[sarabande]

you will almost certainly have difficulties steering unless you couple them together rigidly. If you retain their free-swivelling capability, on a small transom you will end up mincing the blades or entangling the control arms and losing control under power.

And then there is the matter of the joint mass at the blunt end, plus the mechanic's weight. A bit skittish the dinghy she will be.

 

[melandnick]

you will almost certainly have difficulties steering unless you couple them together rigidly. If you retain their free-swivelling capability, on a small transom you will end up mincing the blades or entangling the control arms and losing control under power.

And then there is the matter of the joint mass at the blunt end, plus the mechanic's weight. A bit skittish the dinghy she will be.

Thought about that.
I reckon that they can very easily be joined with a bar accross the handles like the rudder of a cat.
The combined weight of the engines is about 26KG, lighter than most 4hp+ engines so no down side there....pun intended!

 

[cardinals]

I've tried this whilst pursuing my love of 'dangerous dinghying'. I ran a 2.5hp two stroke next to my usual 6hpfour stroke Suzuki on my Loadstar 290. It was much slower to plane and only marginally quicker though it did feel gratifyingly risky. More fun to be had when I tried the 6hp on a 220 dinghy - properly hairy.

You would need to look at prop pitch to get best speed.

Cheers

 

[CharlesSwallow]

if you have a 3.5hp two stroke Mariner, they are like hen's teeth if in good shape. They are lighter than the newer 4 strokes, and should command a nice used price.

Why not sell one on, and then pick up a new fourstroke 6HP for a main engine, and keep one 3.5 Mariner as a backup? If you can strike a good deal with someone who knows the value of the Mariner 2 stroke (someone who wants to transom mount it as an aux for a racing boat), you may not be out of pocket that much...

Really?

I have one, four years old and so far it's only had two gallons of fuel through it since I prefer to row (for the exercise). Perhaps I need to buy a more secure padlock for it. It's been sitting on the taffrail all this time.

Chas