outboard for 3.0 metre SIB

[Elcaro]

Hi all,
I'm thinking of a new o/b. I've got a 22 year old Honda 5 which is a bit temperamental about starting, idling, scary when you drop speed low enough to engage gear in case it stops and won't start again. It's 27 kilos plus of course non-integral fuel tank and fuel line. My back isn't what it was and a couple of years ago I had a hernia op. which I would not like to repeat!
I'm impressed by the 13 / 14 kilo weight of Yamaha / Suzuki 2.5 ish motors.
Would one of these push my 3 meter SIB around?
I might have to get over a bit of tide in the estuary (istr 1.9 kn at worst according to the chart) but generally I'm in no hurry.
Any thoughts pls?
Regards from Terry.

[chipko]

Hi Terry,
A 2.5hp motor should push your sib along at about 5 knots max. Will probably do that speed from around half throttle. Even at full throttle, apart from much more noise, probably won’t go any faster as limited to max displacement speed of hull.
You really need to decide if this will be sufficient for the prevailing wind/tidal conditions in your area.
Currently the lightest at around 13kg are the Honda 2.3 and Suzuki 2.5. The rest, Merc/Mariner/Tohatsu and Yamaha 2.5’s are all slightly heavier at 17kg.
Merc/Mariner/Tohatsu (all the same motor) also do a 3.5hp version which is the same block and weight at 17kg.
Hope some of that helps.

[Stubber]

Hi Terry,
If you want light weight and a little more power per kilo you could obtain a 3.5/3.3 2 stroke as i think these are around the 13 kg range

[jeffstevens763@g]

OMO you don't have much left in terms of power with a 2.5 personally I woul be looking at something like this 10 kg more in weight but a good sack barrow would sort the lifting out

Ron Hale Marine Ltd - Yamaha 8CMHS

[Elcaro]

Hi guys,
That looks a good motor Jeff - and I do have a sack barrow as it happens :-)
Stubber, yes 2-strokes were more power to weight but afaik would have to be 2nd hand now.
chipko - thanks for the info. Say we stick with 2.5 (everything's a compromise) then Honda, Suzuki, Yamaha - which do you think is best? I'm leaning towards the Yamaha cos it looks like you can lie it down on front, LH or RH sides to transport it.
Regards
Terry.

[chipko]

Nowt to choose between the big 5 makes to be honest.
The little Honda’s air cooled but noisy and no gears...centrifugal clutch.
Suzuki is lightest motor with a gearbox.
The Merc/Mariner/Tohatsu are the most powerful in 3.5 guise.
The Yam is possibly the quietest, but not by much, and if you like the facility to lay on any side, then all good.
If you fancy more power then the legendary Tohatsu 9.8 two-stroke weighing in at a poultry 26kg is the way to go. Allegedly, you can even buy ‘cheeky’ new ones from some sources.

[Mikefule]

I used to do long days of scuba diving on a larger SIB with a 3hp 2 stroke motor. That was me and full diving gear and safety gear on sheltered coastal water: Scottish sea lochs etc. I once did 24 miles in a lazy day on the sea lochs with that motor.

I now have a 310 SIB and it will proceed nicely up the river Trent against the current with a Torqeedo electric motor which is "nominally" 1.5 hp.

If you don't want to plane or to fight strong headwinds or currents, you can get away with a very small motor indeed on a 3 metre SIB.

[Elcaro]

Mikefule, thanks, I'm likely to be just in sheltered waters. I'll also have a look at your book.
chipko, thanks, I'll dig around on prices, looks like it might be just down to that. But re the Honda, I don't want noise,and not having a reverse sounds bad enough (but I'll have to accept that at this o/b size), but not having a neutral I don't fancy!
Regards,
Terry.

[Elcaro]

Actually it might come down to a dealer who will give me some PX - locally a place offered me some money for the old Honda 5 so that could be a factor
Terry.

[Elcaro]

Ah chipco, what about Mariner 3.5? 17kg, says it can be laid down on 3 sides ....

Regards from Terry.

[chipko]

As far as I know they can only be laid on one side...well at least ours can.
Otherwise good little motor.

[Limecc]

I'm scarred from childhood fighting a tidal estuary and not being able to make it back to safety because of only a 3.5hp Evinrude.

Forward 40 years, was fine launching into a flooding river Trent which must have been moving at 5 or 6 knots. 3.8m + 20hp was reassuring having four people onboard, a 3m SIB +Torqeedo could not have managed at all even with one person. Not saying you need the max rating, just get something bigger than 3.5hp! Too limiting at best. "Getting away with it" is too risky even unsafe? Hope you have a good anchor and radio lol.

[Max...]

Try and experience one of the tiny little two stroke air cooled motors before buying, noisy, buzzy little buggers.

You don't mention budget but personally for relaxation and all round ability I'd look at a modern Suzuki 4 stroke 6 or similar. 24kg. The 8's go up in weight quite a bit.

If budget lower then still plenty of older used ones around and with many 4/5/6 being the same weight I'd still want the best bang for weight. A 2.5 is OK for pootling from the mother ship to the jetty but will be tiring if out for longer periods.

Here's an eBay search to gauge what's about:

https://www.ebay.co.uk/sch/Boat-Engi...c&LH_PrefLoc=1


https://www.ebay.co.uk/itm/SUZUKI-DF...YGQN:rk:6:pf:0

[jeffstevens763@g]

Terry
the link i gave you if you look on the site at used and new outboards you will get a feel for prices and specs secondhand lightweight outboards are holding their price might be better looking at new for a few hundred more i think the 3.5 mariner on the site is about £599. secondhand £425

[Elcaro]

Thanks guys for all the advice. I keep trying to reply and the replies don't appear in the thread, dunno what's wrong with it or me.
I'm taking the old Honda 5 to a place locally and they'll have a look and see if they want to make a PX offer.
They sell all makes of o/bs.
Regards from Terry.

[phantom 19]

In my opinion all the 2.5hp 4strokes are hateful engines. The Suzuki had a weak gearbox dog, hondas have or had mild steel carb bowls, Yamaha had too lean a slow speed jet in from the factory.

My choice would be a Yamaha Malta 2 stroke or 4/5 2 stroke

[Elcaro]

Ah thanks Phantom19, I'll take that on board. Hmm, Malta - lived there for a few years as a child, courtesy of the British Army. Could be a sign!

Incidentally while playing with the Honda 5 in a barrel yesterday, I found the engine side connector of the fuel line is not great. Bit of a leak at first, then after a while it came off!. So if that's loose and allowing air in, that could account for my problems. So if I keep it I'll replace that connector or the whole line. Still weighs 27 kilos though :-)

Of course the whole fuel tank / fuel line business is a nuisance which a motor with an integral tank would get rid of. (Although you'd have to take a small fuel can with you I guess to top up).
Regards, Terry.

[Mikefule]

Originally Posted by Elcaro

Mikefule, thanks, I'm likely to be just in sheltered waters. I'll also have a look at your book.
chipko, thanks, I'll dig around on prices, looks like it might be just down to that. But re the Honda, I don't want noise,and not having a reverse sounds bad enough (but I'll have to accept that at this o/b size), but not having a neutral I don't fancy!
Regards,
Terry.

Not having a reverse is not a problem. It is common on smaller engines. Instead, the entire engine rotates through 360 degrees in its mount. At low revs, you just spin the engine through 180 degrees, then steer it with your hand on the cowl. Thousands of engines were made like that. In a small SIB you spend very little time reversing.

Not having neutral is a problem in two situations:

1) Picking up swimmers, overboard crew, or mooring buoys. If someone is in the water, you do not want a spinning propeller anywhere near them.

2) If for any reason you want to stop and drift for a short period, such as waiting for another boat to pass, or waiting for a mooring to become clear. Without neutral, you need either to circle at low revs or switch the engine off. Restarting a warm engine can sometimes be trickier than starting a cold one.

There is also the minor problem of a slight "surge" as you start the engine.

Having neutral is preferable, but plenty of people with small boats manage without. Don't forget that you can always do slow manoeuvres near to the mooring pontoon or slipway with oars or paddles.

[Searider]

A colleague of mine has a 3.5hp Mercury 4 stroke, new last year and this will get his Avon 280 airdeck on the plane with him and his (lightweight) son.
He's very pleased with it.