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Advice on inflatables & outboards

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Lots to consider bro. Try lifting it before you buy...
if you want any tips, give me a shout,?i used to drive em and other stuff for a living for a while. Lots of fun, dont forget the safety stuff tho. i sound like a bore, but recent events show what can happen. I might have some bits and bobs to help you along.
 
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15hp two stroke!! what make & model?
Buying your first boat needs lots of revision, please don't rush into any purchase - especially two stroke motors!
Small boats can be very fickle & offer little compromise, so really study the form before you buy.
 
i might as well throw in a few notes if you are interested

Much depends on what you want to do. A small dinghy with a two horse will get you up to a mile or so off shore in ten mins or so and not be any good in waves. Its more like a large support lilo but can be carried and launched easily allowing max time in the water. A 320 dinghy with a ten horse will allow two of you to travel at about 15kts for as long as you have fuel. maybe upto 5 or 10 miles and in greater sea conditions. It will be harder to launch and restrict your ability to change spots if you need to re pack it. If you know of a lot of spots off shore in the same area this is the one to go for, its also a lot of fun but comes with ....choices....

several main types:
large tube : good for carrying bit more weight and hold shape a bit better in the waves
Small tubes : lighter but less rigid. easier to get in but that counts for the water too!
Hyperlon - uv resistant ....dont spose that will be a problem
PVC - less so than above

solid hull and floor deep V - good for waves and kit but needs a bigger engine to lift it onto the plane
Solid floor shallow v - less directional stability but easier to plane. Not so good in waves

Fibreglass fit together floor with blow up keel underneath. Gives shallow v and stable hard wearing platform in boat. Heavy though. Medium directional stability

High pressure air deck floor, good compromise for weight. Prone to damage from sharp objects. Usualy gives shallow V profile

floppy floor with wooden slats. Light but may be difficult to plane. Limited directional stability and easily damaged.

There are some non inflatable collapsing boats worth looking at if you surf around a nit.

All boats should have max rated engine capacity or weight. of course you can exceed it but it often isnt worth doing.

Inflatables are much heavier than they look and a nightmare to row. Often easier to sit in the bows and use one oar like an indian canoe. Dont rely on it.

many dinghies are very heavy and need to have the air sucked out to be able to store properly. Imho A proper electric dinghy inflator is essential for something like a 320. Wheels will probably be needed to get to and from the shore. These can be very light tho so shouldnt discourage you from a bigger boat if thats your bag.

engines.
most manafacturers have several models that they tune or de tune to make intermediate sizes. Eg a 4hp normal tune becomes a 6 with better carb etc. this is important as there are some that will give you the magic 10hp as a tuned 6 rather than detuned 15. This makes a huge difference to weight. Eg new honda four stroke 15 weighs around 46kg plus fuel etc but a tohatsu 9.8 two stroke is about 22kg. Two strokes are more polluting but much lighter and you can lie them down any old way, a four stroke needs to be stored in the right position or oil will leak into the cylinders etc. Remember transom height too. For a small dinghy you really need a short leg.
by the way, you can really only get two stroke second hand in the eu due to pollution laws.

getting set up, you need an anchor, small and collapsable is fine with a metre or so of chain and lots of rope, a painter (rope on the front) preferably short enough that it doesnt tangle the prop, something to tie your engine on with (seen it so many times) , a bailer(boat will always get full of water and become hard to plane). you can cut the bottom off a kids bucket and seal some perspex to the bottom. Tis makes a bailer and a good way to look underwater whilst looking for a spot. Leaning over isnt as easy as you imagine.
Other things you might want to consider are a tiller extension as it can be easier to drive standing up in big waves.
dont pump the boat up too hard on a hot day as if you leave it in the sun(ha!) they can be known to expand and spring a leak on a seam.
waterproof store for 'stuff'

safety
i like a cheap waterproof handheld vhf and a couple of cheap red flares. Had to use the VHF, so like to have one nearby. Learn simple mayday procedure, why not!
an oar
a torch
Water
Dont usually worry about pump or repair stuff as its too awkward in the field.
Kill cord...... Use it. Its not cool to be run down, ive seen it three times now and its really not funny.

Sure other things will come to me, apologies for rambling mail but happy if it helps make some choices.
Typed on ipad so excuse typos!

Pat
 
I am not a huge fan of small inflatables to be honest, plastic boats like jonnys smartwave are so much better is so many ways apart from storage & wieght!
Spears & knifes just dont mix with inflatables & their skittish nature on the water can be really annoying too but of course small inflatables can be great fun & very useful it is just that once you have used a ridged boat you would realise just how much better they are!
How about the potabote!! I still have mine although it has not been used for many years, the potabote gave me some real fun times & the odd scare not to mention the very odd looks from spectators!! Porta-Bote also known as Portabote, Portaboat. Folds to 4 inches(11cm) Flat
Ref 2s v 4s personally I would not give you tuppence for a carb two stroke!
 
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15hp two stroke!! what make & model?
Buying your first boat needs lots of revision, please don't rush into any purchase - especially two stroke motors!
Small boats can be very fickle & offer little compromise, so really study the form before you buy.

It's a 2006 Mariner, the same one as in this listing ( although its not this one I'm buying ): Outboard Engine for sale , 15hp Mariner 2 stroke - Boats And Outboards

At around 35 kg, it seems very light. I'll be having to lie the engine down in the boot of my car, from what foxy said, a 4 stroke would flood with oil... An amazing bit of info, I had no idea about that!

Please can you share your worries about 2 strokes?

I'm doing as much research as I can but I'm very green - the only boat I can have this year is an inflatable as I need something to just stick in the car and go. If I lived near the sea I'd invest in something better but I can't justify the spend this year - an inflatable is the only viable option to me right now.

It will never be used in bad weather as I only go down to the coast when it's nice weather - that sounds stupid but every time I go spearing, I have to factor in £80 of petrol! It's a long drive over the Welsh hills so I try to only to when I can guarentee the viz.
 
PS bit boring but......fork out for a handheld VHF radio (£100). Could be the best £100 you ever spend.

Absolutely! Will certainly be buying one! Massive thanks for your advice Dave, it's been invaluable!

You will have a lot of fun with a 15 2 stroke on a 3.2 - my 9.9 with just me in at full throttle can be a bit twitchy lol - on a more sober note use your kill cord !

Have no fear Rob - after recent events, there's no chance of me not using it.
 
no worries bro, help it helps. for info, you can lie a four stk down but has to be on correct side etc. Also I had a tohatsu 9.8 two stk and took it round the world as a tender and it never failed. every engine different though. I also had a portaboat, that was the one i was trying to remember.... Lots of fun and sturdy too. Ugly as sin though!
 
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Can anyone advise me on what size fuel tank I should get for a 15hp? Can I keep it nice and small with a 12L tank or should I go for 22L.

I'm guessing a 12L will be fine?
 
Hmm..., 12l for my 9.9 2 stroke, usually im only out for a couple of hours tops few different spots and thats it - i dont think you would need a 22l for say a morning or afternoons use. And the weight of a 22l fuel tank full is pretty heavy. However if your thinking of pushing further away from your launch spot or spending the whole day afloat then 22l may be the better bet especially if your a full throttle kind of bloke !
 
One reason why I don't like 2s is due to the fuel consumption.


35kg might not be heavy in the gym but outboards are just about the most ungainly dead weigh Imaginable.
 
Have to agree on the weight thing. 22 kg needed to be winched up onto the yacht. Not sure I could manage a 30kg, its just too awkward.
 
I don't think 35kg will be a massive be a problem for me, I understand that 'gym-weight' and 'ungainly-lump -weight' are completely different but at most I'll be taking it from the back of the car and placing it straight on the transom to be wheeled off.

One reason why I don't like 2s is due to the fuel consumption.

Might be wrong, but from what I'd read, the fuel consumption on modern 2 strokes wasn't too far away from that of a 4 stroke - to be honest though, I'm not going to be putting vast number of miles on it so hopefully won't be too much of an issue.
 
Well I did try to warn you away from the dreaded two stroke but you seem pretty keen so I hope it works out for you.
All carb 2s burn fuel at twice the rate of a 4s, the modern fuel injected 2s are a different matter & are much more fuel efficient.
However the quiet running, super reliability of the modern 4s & most importantly (for me at least) is the fact you can idle & run slow with a 4s - that is something a carb 2s does not like.
 
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12 litre tank will be fine for a few hours. what size inflatable are you thinking of at the mo?
 
Well I did try to warn you away from the dreaded two stroke but you seem pretty keen so I hope it works out for you.

Why is it dreaded? Ah, so much conflicting information everywhere! As it's quite a new engine, 2006, surely it would be fuel injected?

I'm not going to get a 4 stroke 15 as I don't want a 50kg+ lump and I'm not paying £2.5K+ for an engine I'll realistically use maybe 6 weekends this summer ;)

Basically I just want something light and powerful that can get me from A to B in a timely manner - I don't think it can be that terrible a choice?

12 litre tank will be fine for a few hours. what size inflatable are you thinking of at the mo?

I'll probably go for something around 310 - 330 and upgrade to something bigger next year. I think I might get a 22L tank, it's not vastly bigger and it'll mean I can fill it up for the weekend with nice, cheap English petrol, not rural Welsh petrol, which costs a 20% premium rofl
 
OK mate that is cool, I am probably well out of touch... enjoy you boating :)
 
OK mate that is cool, I am probably well out of touch... enjoy you boating :)

Living on Guernsey?? :hmm :D

.................although had to chuckle as I ....am now also*/may live to regret being* .... the owner of an old 2 stroke 15hp Yamaha!?? :D


*delete as appropriate :D
 
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Fuel injected 2 strokes, modern 4 stroke?....bah.
All you need is a 1968 Seagull Silver Century. Two divers, dive kit, 100kg of recovered "treasure" and a ten mile round trip in a 3.4m Avon and it didn't miss a beat.
We were deaf and covered in 10-1 mix fumes at the end of it though. I think we burnt through the grand total of 7 litres of premix.
We landed on the beach and an old lady came over with her grandaughter, pointed to the engine and said "We used to have one of those on our boat 40 years ago".
 
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Checked up with the maritime dept gwynedd council. £20 all in for up to 10hp. Or 15hp without the stickers on it:)
 
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