Advice on choosing outboard for sailboat with engine well

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Samoddie

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Hi,

I am hoping to replace my existing outboard in my 22 foot Anderson. The boat has an engine well, and I am advised by a fellow Anderson owner that the width of this restricts brand choice. This directs me to Mercury Mariner. The agent I have been in touch with has suggested I buy a sail drive, but these only seem to be available in long shaft, which undermines the point of engine change (I want to be able to stow the engine in the relevant locker while sailing).

Arguments for ‘saildrive’ seem to focus on 1) presence of charging coil and 2) prop/ engine/ revs/ boat speed.
1) would be nice, although it must be said I blew my solar charge controller last time connected my current engine up!
2) I don’t really understand. I can understand that there is some kind of theoretical advantage.
So, my question is - how much does it matter to buy an engine configured for a sailboat? My interest is in having a way of staying safe when there is no wind, or a horrible current/ traffic etc. But I am not really buying outboard for long distance cruising under powere - that would be a bad outcome!

What do people think/ know from experience?

Thanks

Sam
 
Electricity very attractive, but not much mains power where I am, and I have determined that petrol better suits my purposes in this instance. Not like car…
 
An outboard gives it’s rated power at a certain rpm band, and that is usually it’s max rpm, usually described as Wide Open Throttle WoT. Different pitched propellers give different WoT rpms depending on the load. Most small short shaft outboards are sold with props suitable for tenders, and on a heavier boat they won’t achieve their best WoT hence rated power, unless you buy a shorter pitched prop which will allow the motor to rev high enough.
Fairly easy to calculate on larger motors that have tachometers, but on a little 4-6hp typical, you need a strobe light to see what your WoT is compared to what it should be.
Sail drive outboards typically come supplied with shorter pitched props.
 
Samoddie said:
Hi,

I am hoping to replace my existing outboard in my 22 foot Anderson. The boat has an engine well, and I am advised by a fellow Anderson owner that the width of this restricts brand choice. This directs me to Mercury Mariner. The agent I have been in touch with has suggested I buy a sail drive, but these only seem to be available in long shaft, which undermines the point of engine change (I want to be able to stow the engine in the relevant locker while sailing).

Arguments for ‘saildrive’ seem to focus on 1) presence of charging coil and 2) prop/ engine/ revs/ boat speed.
1) would be nice, although it must be said I blew my solar charge controller last time connected my current engine up!
2) I don’t really understand. I can understand that there is some kind of theoretical advantage.
So, my question is - how much does it matter to buy an engine configured for a sailboat? My interest is in having a way of staying safe when there is no wind, or a horrible current/ traffic etc. But I am not really buying outboard for long distance cruising under powere - that would be a bad outcome!

What do people think/ know from experience?

Thanks

Sam
Click to expand...
The shaft length is determined by the height of the mounting board above the waterline - approx 16^ for short (standard) and 20" for long. So first and most important measure that dimension as it is critical for the engine to run properly. Too short and the prop won't be immersed, too long and and you will have exhaust back pressure problems.

The "saildrive" engines are specifically set up with a larger, slower turning propeller suitable for a heavy displacement (relatively) boa for speeds of 4-6 knots whereas the most common use for small outboards in the 6-10hp range is for small light boats that are capable of planing speeds which needs a small high revving propeller.

Outboards in general are not ideal for auxiliaries on sailing boats but the saildrive models are the best you can get.
 
Fine pitch prop as in sail driver gives max thrust at low boat speeds. it should be possible to buy a fine pitch prop for standard leg length o/b. However fine pitch means higher RPM at no wind cruise speed. While in no wind a standard pitch (course) will still move the boat along nicely like 5knots at low rpm lower noise. But if you find you need to bash into strong winds and waves you might appreciate the fine pitch more thrust option. Charging coil to my thinking on a sail boat is pointless if you don't use the motor much. ol'will
 
You don't need strobes. It's a fact of life that 'regular' small outboards will have props suited to a small light high speed load and will not be able to produce anything like their rated power when driving something like an Anderson 22. You can buy (at a price) an alternative prop for some outboards which will better suit your purpose (i.e. you do not necessarily have to get a 'sailpower' one to get an appropriate prop), but the correct length (standard or long shaft) is also important, and an effective charging coil is a boon.

To the OP I'd suggest he considers carefully the recommendations of experienced existing A22 owners, and whether the outboard could be accommodated: Could the locker be extended, or a hole (with lid?) made in it so that part of the outboard projects out of it.? Could an arrangement be made by which the outboard is supported above the well and out of the water? If the storage is only for when the boat is not in use, could it not go on the cockpit floor, with some means of securing it against theft (padlock & chain? bars between the cockpit seats?) and a (loose?) cover to protect it from the elements?

I'm not familiar with the Anderson 22 outboard set up, but from my experience with a Hurley 22 (which I cruised extensively) with outboard in a well, I'd caution against getting an outboard so big and heavy its difficult to get into and out of the well position (I ended up leaving the outboard in position even when the boat was unattended, just lifting it now and again to clear it of fouling). In my case not only did the size of the outboard (8hp 2-stroke twin, IIRC) make it difficult and unpleasant getting the outboard in and out of position, but it prevented the outboard from being turned from once side to the other at all, which would have been useful. The prop was not suited to the boat, so I didn't even have the benefit of the power of the larger outboard. Had I had the available money I would have bought a smaller outboard for it, with a long shaft, low speed high thrust prop, and a decent charging coil (the lack of the latter was a pain in the backside for cruising).

Good luck with whatever you choose.
 
Hello Sam, welcome to owning the best and fastest boat ever! ;-)
I use a 5hp 2-stroke Mariner which will push Rum Run along at 6kn when the bottom is clean. It lifts out of the well quite easily.
If I had to use a 4-stroke , I would look very carefully at the weights of 5hp and 6hp outboard and not choose a big weight penalty to gain a mostly pointless 1hp.
In calm weather, the boat will move with a Seagull Featherweight pushing her - slowly. This engine is barely 1hp /45lbs of thrust.
In not calm weather, you can sail! Actually going into a river entrance dead upwind against a tide sometimes needs the 5hp. I am always glad to turn the noisy object off though.
Don't bother with a charging coil, they don't have enough output. Put a semi-flexible solar panel on the hatch or hatch garage or both.......
I have found that if motoring up tide, pulling the keel up helps quite a lot.
 
All well and good ... but at end of day the real practical difference of props is academic.

I have and my Father had various boats with outboards ... approx half were Saildrives ....
My Alacrity 19 and Snapdragon 23 - both had 'normal' and 'saildrive' version O/bds while I owned them .... did I notice any real difference ? Actually no.
My Kormoran has a Johnson 5hp 2str ..... admittedly only 17ft ... but more than enough for anything.

I do say though ... the Saildrive O/bds were heavier due to different gearbox ... especially the Mercury I had on the Snapdragon.

To OP ... with it being an engine that will be used for departure / return to mooring or those no wind days ... I suggest measure the leg length needed to clear hull to drive the hull and just go for a decent brand ... not worrying whether S/D or not. As Rum Run shows ... a typical 5hp does the job ... and even though a 2str may not be so economical as a 4str .. its generally lighter, smaller and easier to look after .. (means searching the 2nd hand ads of course !)
 
Thanks all. Storing a bigger engine is comprehensively not an option, unles inside, which defeats part of the object of new engine. 2 stroke would be ideal, but another objective is high degree of reliability, which is not something outboards are famous for in my limited experience. Sounds like non saildrive IS reasonable option. Shame about coil - I already have 60w solar on homemade fibreglass garage - which worked very well last summer. Really helpful.
 
I had a long shaft 5hp outboard on a bracket on my kestrel 22. It was ok in flat water but a waste of time in any chop as the prop was out of the water on every wave and we couldn't make much headway. I guess it would be ok in a well
 
Samoddie said:
Thanks all. Storing a bigger engine is comprehensively not an option, unles inside, which defeats part of the object of new engine. 2 stroke would be ideal, but another objective is high degree of reliability, which is not something outboards are famous for in my limited experience. Sounds like non saildrive IS reasonable option. Shame about coil - I already have 60w solar on homemade fibreglass garage - which worked very well last summer. Really helpful.
Click to expand...

Reliability of O/bd ?

Its the old matter of use. A regular used motor will keep on going ... but those that have a long storage / lack of use can end up hard to start etc.
I much prefer the simple 2str ... no worries about how you lay it down in locker ... usually lighter and smaller than 4str. On stopping engine - best is to turn off Fuel - not use the Stop button ... let carb run out and have minimum remaining in it. That not only helps to stop clogged jets - but reduces spillage in locker.
The size of O/bd suitable for your A22 ... would most likely have integral tank ... this then has to be accounted for when storing in locker.
The output of a coil on such a small engine - in fact even on larger O/bds is pretty limited - especially if you are only running it for short periods. Maybe best to look at alternative charging means for your batterys.
 
38mess said:
I had a long shaft 5hp outboard on a bracket on my kestrel 22. It was ok in flat water but a waste of time in any chop as the prop was out of the water on every wave and we couldn't make much headway. I guess it would be ok in a well
Click to expand...

Its always a problem .... but even a well is not a complete answer as the prop is still often high up ...
 
I know that trying to buy a new 2 stroke outboard is a bit like trying to buy alcohol in Iran, but the recommended engine for a 22 in the Anderson Association website is something like the 5hp 2 stroke mariner.
The boat was designed to have a relatively lightweight engine so that is was possible to lift it out of the well and store in the transom locker when sailing, the problem now is that 4 stroke engines are heavy and not so easy to lift out of the well.
With respect to Tranona, #5 saildrive is great for some boats, but not sure it’s suitable for the Anderson.
Maybe best solution ix to look around for a good condition s/h 2 stroke 4 or 5hp and fit a solar panel as suggested by rum run in #8.
 
Praxinoscope said:
I know that trying to buy a new 2 stroke outboard is a bit like trying to buy alcohol in Iran, but the recommended engine for a 22 in the Anderson Association website is something like the 5hp 2 stroke mariner.
The boat was designed to have a relatively lightweight engine so that is was possible to lift it out of the well and store in the transom locker when sailing, the problem now is that 4 stroke engines are heavy and not so easy to lift out of the well.
With respect to Tranona, #5 saildrive is great for some boats, but not sure it’s suitable for the Anderson.
Maybe best solution ix to look around for a good condition s/h 2 stroke 4 or 5hp and fit a solar panel as suggested by rum run in #8.
Click to expand...

Absolutely.

It has to be taken into account that boats such as this were designed in the heyday of 2str O/bds .....

Of course you could go down to a smaller size in 4str ........ but then its unlikely to get leg length and the performance will suffer.
 
On Achilles 24, little bigger boat, I was happy with 3.3 Mercury 2 stroke. Gave boat enough power to motor around local area, with occasional longer motoring. It is thirsty though - at least 2 liters per hour. If you really need an outboard for getting in/off mooring, I would consider 2 stroke 3.3 Mariner/Tohatsu/Mercury. Mine was properly serviced before I bought it and haven't had an issue with starting or so for 4 seasons - now I am planning to service it, although I use it only for dinghy now. It is simpler than any 4 strokes - fewer things to go wrong, lighter - so easier to take out during sailing.
 
I used to have a 1,500kg, 24ft boat with an O/b well. For the use of getting on/off the mooring and running for <15 mins a time a Yamaha 8hp worked well but was probably overkill. Once sailing, taking the O/b out and the well plug in gave us about an extra knot of boat speed.

Nice and easy to take the o/b home to service in the comfort of the garage too. As a set up for a small boat, it is highly recommended.

However, we took that boat through the forth/clyde canal once - having a 2stroke in a well in the cockpit is seriously loud when you motor for more than a few minutes at a time. Standing next to it for 6 hours and I was ready to chuck it in the canal!

If you plan to motor for any more than just in/out of the harbour before getting the sails up, I'd get the quietest 4stroke it's possible to get. If however you just want to run it in/out of a harbour then if I had my time again, I would have an electric outboard and take the battery home after each day sail to charge at home...
 
Samoddie said:
Thanks all. Storing a bigger engine is comprehensively not an option, unles inside, which defeats part of the object of new engine. 2 stroke would be ideal, but another objective is high degree of reliability, which is not something outboards are famous for in my limited experience. Sounds like non saildrive IS reasonable option. Shame about coil - I already have 60w solar on homemade fibreglass garage - which worked very well last summer. Really helpful.
Click to expand...


As the others have said, I think you are on the right track, a smaller engine has a lot to recommend it. You might like to look at something like the Tohatsu 3.5 4 stroke, standard shaft, it would be out of the water now and again but with an offset well you learn to compensate.
My only doubts about 2 stokes, in a well (which I have used a fair amount, big and small), is the degree of smoke you have to put up with if motoring in light following winds, plus they can be noisy.
 
doug748 said:
My only doubt about 2 stokes, in a well (which I have used a fair amount, big and small), is the degree of smoke you have to put up with if motoring in light following winds, plus they can be noisy.
Click to expand...
The fumes never really bothered me, but it was noisy. Not sure if 4 strokes will be better, as the noise might be magnituded by the engine position in the well.
 
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