Quick outboard question

Thedreamoneday

Thedreamoneday

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I've decided to buy an outboard as a backup for my Westerly Nomad 22, the question is what would you say is the minimum hp (5?) and what type of shaft (long?) if I go for long can that just clamp on the transom of should I get a bracket.

I have some sort of bracket on the transom but unsure what else is needed, I'll try an post a picture to illustrate.

I've just previewed and it's not the clearest picture, I'll try and get abetted one later.

Thanks
 

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Thedreamoneday said:
I've decided to buy an outboard as a backup for my Westerly Nomad 22, the question is what would you say is the minimum hp (5?) and what type of shaft (long?) if I go for long can that just clamp on the transom of should I get a bracket.

I have some sort of bracket on the transom but unsure what else is needed, I'll try an post a picture to illustrate.
Click to expand...

If it's just as a backup to an inboard then no need to get a big outboard. Even 2hp would get you home just fine, although perhaps a wee bit slower than usual. If I were you I'd be looking for a Seagull Silver Century, which has a large, slow-turning prop and will easily push you along.
 
JumbleDuck said:
If it's just as a backup to an inboard then no need to get a big outboard. Even 2hp would get you home just fine, although perhaps a wee bit slower than usual. If I were you I'd be looking for a Seagull Silver Century, which has a large, slow-turning prop and will easily push you along.
Click to expand...

Yes, it's just as a limp home motor, an really I could do with it being less bulky but would a 2hp get me through a fiscal current? (Mersey)

Thanks
 
fiscal ? Does money flow in the Mersey ?


I thnk you have the remains of sprung loaded outboard bracket like the one here (half way down)

http://www.angleseymarinesupplies.com/auxilliary-outboard-brackets.php


I have a similar one and use a 3.5 Mercury o/b on it. Works fine, but you need to get the prop at the right height relatively to the water level, so measure up first. Too deep and back pressure can cause the o/b to stop; too shallow and the prop breaks surface with possible cooling water interruption. The adjuster works well.
 
Thedreamoneday said:
Yes, it's just as a limp home motor, an really I could do with it being less bulky but would a 2hp get me through a fiscal current? (Mersey)

Thanks
Click to expand...

It depends on the weight of the boat and the strength/direction of the tidal stream. We have a Tohatsu 3.5hp which pushes our 1100 kg boat along fine at about 3-4 knots with no current, but it obviously wouldn't make any headway at currents near or in excess of that. I would have thought you would need more than 2hp just for safety's sake. A 5hp would probably do the job.

A good accountant, though, would probably help you get through a fiscal current, whatever that is!

R.
 
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rbmatthews said:
It depends on the weight of the boat and the strength/direction of the tidal stream. We have a Tohatsu 3.5hp which pushes our 1100 kg boat along fine at about 3-4 knots with no current, but it obviously wouldn't make any headway at currents near or in excess of that. I would have thought you would need more than 2hp just for safety's sake. A 5hp would probably do the job.

A good accountant, though, would probably help you get through a fiscal current, whatever that is!

R.
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Looking at the documents she's about 1500kg so I think as you say a min of 5hp to be on the safe side, don't really want to be screaming the motor and standing still especially with the limited time I have to get in through the lock at the marina.

Can anyone advise on shaft length? Would I need a long shaft?

Thanks
 
sarabande said:
fiscal ? Does money flow in the Mersey ?


I thnk you have the remains of sprung loaded outboard bracket like the one here (half way down)

http://www.angleseymarinesupplies.com/auxilliary-outboard-brackets.php


I have a similar one and use a 3.5 Mercury o/b on it. Works fine, but you need to get the prop at the right height relatively to the water level, so measure up first. Too deep and back pressure can cause the o/b to stop; too shallow and the prop breaks surface with possible cooling water interruption. The adjuster works well.
Click to expand...

Flippin auto spell :-)
 
Thedreamoneday said:
Yes, it's just as a limp home motor, an really I could do with it being less bulky but would a 2hp get me through a fiscal current? (Mersey)
Click to expand...

Have you reason to believe that your inboard will be unreliable? If so, and if it's an issue you can do something about, I'd start off getting that sorted first. I see your point about the current, but remember that in limp-home mode there might also be the option of dropping an anchor until the current drops.

The large prop on the Silver Century makes it extremely effective at shoving a heavy boat along, even though it only has a nominal 3hp or so behind it.
 
As the others have implied there are really two answers.

To shove you along on that bracket and buck a bit of adverse tide with power in reserve, I think you need a longshaft 5hp. Just to get you home, biding your time, in flat water then a longshaft 3.5 Tohatsu (or similar, perhaps even ss on a lowered bracket) could do the job. This, of course, would be of limited value against a sharp tide or headwind.
A smaller engine can also be used on the tender, a big plus.

I have shifted my 4ton boat back to base (5 miles ish) with a 2.2 outboard but it is slow work and I had no fiendish currents to contend with. Using a small engine on an inflatable lashed alongside works very well, as the prop stays in the water all the time.
 
As already suggested that plate is part of a swingdown bracket. To fit an outboard you will need a similar kind of bracket and it should be mounted so that you can use a long shaft outboard. The key measurement is from the top of the mounting board to the static waterline which needs to be 20". If you mount it lower to use a standard (15") shaft the power head will end up too near the water and too low down for you to reach the controls. Your motor will only be of practical use on this boat as a long shaft is not suitable for use on a dinghy. A 5hp will be enough and as JumbleDuck suggests a seagull Silver Century would be ideal. However these are now old and considered antisocial so a modern 4 stroke is probably more realistic.

However, it is really overkill to go this route, as well as being a lot of money if you buy new. The money would be better spent on ensuring your inboard is reliable. the chances of you having to use it in anger are very small and in the meantime you have an expensive limp of machinery hanging on the back of your boat doing nothing.
 
Tranona said:
The key measurement is from the top of the mounting board to the static waterline which needs to be 20".
Click to expand...

My understanding is that the measurement should be to the bottom of the hull where the engine is to be mounted rather than to the waterline, otherwise the anti-cavitation plate and the prop run the risk of being shielded by the hull, resulting in reduced efficiency.
 
Depends on the depth of the hull. on the OPs boat the bottom of the transom is just on the waterline. The outboard and prop would also be well clear of the back of the boat when on the mount. If the transom was different with the outboard on the transom and a deep underbody you might need to set it lower, but with some engines this creates back pressure problems.
 
The engine on Jissel (24ft Snapdragon) was unreliable for a while before dying completely so, when it din't want to play, we put the Tohatsu 3.5 2T from our dinghy on the back and it pushed us along quite nicely in flat water at around 4 knots without too much effort. However, it tended to lift from the water when things started getting a bit lumpy. As a get-me-home measure it's fine, but that was all. Punching a spring ebb into Portsmouth Harbour isn't going to happen.

One tip, learned the hard way: If you use the OB from the tender as a backup for the main boat, make sure it's on the back of the main boat when your going places, not on the dinghy. If you leave it on the dinghy, your main engine will die and it'll be in a place where you've got no time mess around moving the OB or in conditions where you really don't want to be doing that sort of thing (done both - I'm a slow learner!)
 
I've got a Tohatsu ultra longshaft 6hp on a 1 ton 25' cat. Very pleased with it. Burbles along at hull speed on a little over half throttle. The prop has great grip in the water, and the shaft is so long that it stayes submerged enen in choppy conditions. Weight 25kg.....

Once you go over 6hp the weight of the engine nearly doubles.
 
I had a 9.9 Johnson LS on my Westerly 25 & it was plenty of power, a 5hp will just about do you, but you will struggle to stem a spring tide on the Mersey even with a 9.9, especially in wind over tide (common on the ebb) as any o/b will come out of the water in short steep seas.

Anchoring in the Mersey is not generally a good option, you will need an awful lot of chain and/or need to be over a mudbank out of the channel. Finally, in slack tide conditions a 2hp on your tender, tied alongside (& with the o/b tiller tied straight) will allow you to motor home, but it's really not to be relied on if the tide is running unless it is with you & even then, entering the marina will be a bit hit & miss.

Really, I will repeat my recommendation to sail somewhere a bit less unforgiving at least for a few years until you have more confidence & experience.
 
JumbleDuck said:
Have you reason to believe that your inboard will be unreliable? If so, and if it's an issue you can do something about, I'd start off getting that sorted first. I see your point about the current, but remember that in limp-home mode there might also be the option of dropping an anchor until the current drops.

The large prop on the Silver Century makes it extremely effective at shoving a heavy boat along, even though it only has a nominal 3hp or so behind it.
Click to expand...


No reason to think my inboard is unreliable, it's been serviced well and all electrics replaced but it's old so for a few hundred £'s it's a no brainer to me especially being inexperienced. It'll just give me p.o.m.
 
Searush said:
Really, I will repeat my recommendation to sail somewhere a bit less unforgiving at least for a few years until you have more confidence & experience.
Click to expand...

I appreciate your recommendation and trust me I'm not about to just go steaming out into the Mersey on my own- I've already started speaking to people around the marina and have a good friend who's keen to get back on a boat after a year or so on land who has a large number of years experience in tidal waters- he's who I'll be doing my initial voyages with. In the mean time I'm just getting a feel for her 'tootling' around the marina an waterways which in all honesty I'm really enjoying.

Nice and slow, no rush! :D
 
Thedreamoneday said:
I appreciate your recommendation and trust me I'm not about to just go steaming out into the Mersey on my own- I've already started speaking to people around the marina and have a good friend who's keen to get back on a boat after a year or so on land who has a large number of years experience in tidal waters- he's who I'll be doing my initial voyages with. In the mean time I'm just getting a feel for her 'tootling' around the marina an waterways which in all honesty I'm really enjoying.

Nice and slow, no rush! :D
Click to expand...

good answer! it's all good for gaining familiarity with the boat & how it handles in close quarters - enjoy! At 6'62 beam & about 3'6" draught, you'll probably be OK up the Leeds Liverpool (at least once you reach Ormskirk that is).
 
Searush said:
good answer! it's all good for gaining familiarity with the boat & how it handles in close quarters - enjoy! At 6'62 beam & about 3'6" draught, you'll probably be OK up the Leeds Liverpool (at least once you reach Ormskirk that is).
Click to expand...

That sounds great- the mast is still off her so ill probably keep it off for a few months exploring :D
 
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