2 or 1 engine - Page 2

Danork · 05 August 2012, 01:46

I was out tonight (last night now). First night Ribbing run for me! Amazingly hard to spot creel lines at night!... I digress!
I don't know. So many far more experienced folk against the idea of twin setup. Counter rotation problem, the steering issue (I had thought of upgrading to hydraulic steering) weight, drag etc etc.
I know I could probably buy a bigger rib for not much more than I have spent/ am thinking of spending... But as I say I like the size of my rib and a cheap ish bigger boat would likely have an older outboard that might be not that reliable.
A 50hp new honda is very economical, is reasonably light...
I'll think about it some more in the morn!
Cheers everyone for the input. All very helpful. 35knots with the 50 would sure make the trip to Fair Isle much more feasible!
danork

jyasaki · 05 August 2012, 02:00

2 x 20's vs a single 50? I'd go with the 50 hands down.

2 x 20's will give you about the usable power of a single 30 or so (extra drag from the lower unit, additional weight, etc), and twice the maintenance costs of a single. You do get redundancy (though as kubcat said above, it's a tradeoff there as well), and get to do some nifty maneuvering once you figure out throttle control with twins, but I'm not sure either of those offset the other factors. Depends on what you do with the boat, though.

jky

Copinsay · 05 August 2012, 13:43

Hello Dan

I had lots of thoughts on this too, purely from the safety angle, as we are often both in areas where there's not a lot of other traffic at times.

The deal was mostly set by not having room for an aux engine. Plus chatting with people (including RNLI friends) they were not wholly in agreement that an aux or twin engine set up was actually better for safety, due to a lot of the issues already mentioned.

So I've gone for using the cash saved to take very good care of my single 60hp, adding water filter in fuel line, taking lots of spare kit, getting good basic training, plus having for safety each time PLB, AIS, 2x DSC radios, flares, 3 types of anchor, 2x25 and 2 x5 litre fuel, backup paper charts if GPS goes down, and always calling in and out with Shetland CG. I know some would say over the top, but where we are I feel sensible. And of course a life jacket for the dog!

Ideally I'd like a backup engine, but as that can't be done this seems to me a good compromise.

Plus my RNLI contacts felt that they really did not mind call outs when people have taken all reasonable precautions, and recognise that engine failure can happen with any setup.

Hope that helps on the decision I came to... I'm sure other will have different views though.

Best wishes

Steve

Copinsay · 05 August 2012, 13:45

PS - that said, I realise you are not quite as handy for the RNLI as we are down this end.

spartacus · 05 August 2012, 21:49

Quote:

Originally Posted by Copinsay

Ideally I'd like a backup engine, but as that can't be done this seems to me a good compromise.

I managed to squeeze a Tohatsu 3.5hp auxilliary on my last boat - a Zodiac Pro 420 with an adjustable Plastimo transom mount. Little bit Heath Robinson, but it can be done. I'm sure the Bombard 500 transom is roughly the same width? All your other safety measures are commendable. I'm just back from my annual two weeks in Lewis (West Loch Roag). Break down there, and you might pass close to St Kilda or the Flannans. Next stop Nova Scotia!

Pictures of how I fitted it.

Danork · 06 August 2012, 07:21

Thanks Copinsay and spartacus.
I think that looks a very neat setup on the Zodiac.
Yes Copinsay I hear what you say. Preparation and preventative maintenance etc is a very sensible thing to take seriously... (anywhere but certainly away from busy touristy areas).
As I have said before, if I were in more touristy waters I would not be thinking about the two engine idea. I covered 50 miles the other evening and saw 1 container ship.
But, I cannot ignore everyone. I will think I will look into the single engine setup again.
Thanks everyone for idea and suggestions
Cheers
danork

Copinsay · 06 August 2012, 10:18

Hello Spartacus

That's so helpful - thank you. Especially as the build of your boat looks very similar to mine, which given the makes I guess is not surprising.

I really had ruled out fitting an aux engine (as had others), but this seems to have turned that around. I especially like the idea of it being completely independent.

You've prompted lots of questions now, and hope you can find time to answer these please - happy to do this privately, although I'm sure discussing it on here will help others too.

Good too that you clearly understand the situations that Dan and I are Ribbing in - hope you had a great trip to the Western Isles.

I attach some pics of the transom on my RIB - would you be so kind as to see how this compares with yours.

The depth from the top of the transom to the lowest centre point is 550mm and the depth from top of transom to the hull edge in the middle of the port-side gap between the sponson and engine in 480mm - ie where the aux would go.

The width available between the engine casing and sponson on furthest lock is 300mm.

How does it perform?

What was the installation like... You say Heath Robinson, but to me that looks pretty neat and simple.

I take it it's the long shaft version?

Did you look at any other engines?

Many thanks for your help

Steve