4strokes happy on their backs?

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sam_uk

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I sail a Kingfisher 20.

I am planning to replace my existing main outboard with a 6hp as the one I have is getting long in the tooth.

It lives in a well and swings out of the way (shown in green in image below)

http://kyoa.org.uk/Images Web/K20+technical.gif

Are there any 6hp 4strokes that would be happy at this angle?

(I also have a transom mounted 4hp as a auxiliary, so don't want anything heavier than 25kg)
 
25KG is probably the light end of the weight for a 6HP 4 stroke as they are much heavier than a 2 stroke of same power rating. Tohatsu 6HP is 25KG, Honda 5HP is 27KG+ for example. They tend to be a bit bulkier too so you would need to check you have the swinging room in the cut-out. A 4HP could well be sufficient for a Kingfisher.

I would have thought the angle would be ok as you normally carry it that way up anyway. It's lying flat on their wrong side they really don't like.
 
I would have thought the angle would be ok as you normally carry it that way up anyway. It's lying flat on their wrong side they really don't like.
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Generally they can lie on one side or the other.

They are, I think you will find, normally carried by a handle on the back ... the opposite way to the way one normally carries a 2 stroke.

In this case you appear to want to store it part way between upright, which is of course fine, and on its back which I think you may find is generally not acceptable.

I think you may find it difficult to get hard and fast advice about this half way position.

I suggest you consult the owners manual ... most can be found on line .. for any engine you fancy.
If you discover it is Ok on its back then what you want to do will be fine.
If you find it should not be lain on its back then either look at another model or look at one in real life and try to ascertain just how far away from upright will be OK.
 
Carrying handle on my Yamaha was at the back but on my Tohatsu (Mariner/Mercury) is at the front.
I haven't looked inside them but think that the problem with oil is that if you put it on the wrong side oil can run up the tappet chest into the cylinder via an open valve. This risks a a hydraulic lock when starting and the possible horrible damage that ensues.
Can't see that happening in the position illustrated.
An email with the illustration to the tech dept of the importers should get an answer.
 
Lakesailor said:
Carrying handle on my Yamaha was at the back but on my Tohatsu (Mariner/Mercury) is at the front.
I haven't looked inside them but think that the problem with oil is that if you put it on the wrong side oil can run up the tappet chest into the cylinder via an open valve. This risks a a hydraulic lock when starting and the possible horrible damage that ensues.
Can't see that happening in the position illustrated.
An email with the illustration to the tech dept of the importers should get an answer.
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Oil can also leak out via the breather or via the carb .

From what you say one of the Tohatsu clones should be a good choice. BUT according to the Tohatsu owners manual they should not be carried or laid on their backs!
 
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VicS said:
BUT according to the Tohatsu owners manual they should not be carried or laid on their backs!
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Depends on you definition of back and front.
If I had a motor stood on it's leg and I wanted to lay it on it's back I would lay it on the transom bracket.
That would mean the OP's illustration would be tilted the right way.

My Mariner and Tohatsus both had their carry handle above the transom clamp.

Onboat2.jpg


Most outboards have their carry handle there

outboard-honda-bf2.jpg
 
Lakesailor said:
Depends on you definition of back and front.
If I had a motor stood on it's leg and I wanted to lay it on it's back I would lay it on the transom bracket.
That would mean the OP's illustration would be tilted the right way.

My Mariner and Tohatsus both had their carry handle above the transom clamp.
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The side facing towards the front of the boat is surely the front.
Whatever
If you look at the
Owners manual for the Tohatsu on page 34 it clearly indicates that it should not be laid down or carried with the clamp bracket upper most.

It should NOT be carried by the handle above the clamp bracket!

The same also applies to the Honda, regardless of the way the engineer in your second photo is holding it.

CarryTohatsu.jpg
 
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The owners manual for the 4,5, and 6 hp mercury and Mariner engines says they should not be stored or carried on either their front or their backs.

They should be carried upright and if laid down only on the side of the tiller.
 
Fantasie 19 said:
So basically we are agreed that 4 strokes are a PITA, and the OP should either refurbish his current engine, or shop around for a newer 2 stroke... :D
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Fantasie 19,

totally agree, and if you can get one - hint, Ireland - a 5hp 2 stroke is the way to go, I've motored across the Channel Poole to Guernsey in calms a few times, they seem fine to me, and don't require King Kong to lift & stow them !

The idea of carrying 2 engines on the back of a 20' sailing boat makes me cringe.
 
Seajet said:
Fantasie 19,

totally agree, and if you can get one - hint, Ireland - a 5hp 2 stroke is the way to go, I've motored across the Channel Poole to Guernsey in calms a few times, they seem fine to me, and don't require King Kong to lift & stow them !

The idea of carrying 2 engines on the back of a 20' sailing boat makes me cringe.
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OK thanks for the responses.

Regarding the two engines thing: I sail in the Severn estuary. Sometimes I want extra grunt and so I can use both the transom mounted engine, and the well mounted one simultaneously. They are both 4hp currently.

I get great economy when just using just the well mounted one, yet have the power when I need it. Also the chances of both engines failing on the same day is slight.

Cringe away :)
 
sam_uk said:
OK thanks for the responses.

Regarding the two engines thing: I sail in the Severn estuary. Sometimes I want extra grunt and so I can use both the transom mounted engine, and the well mounted one simultaneously. They are both 4hp currently.

I get great economy when just using just the well mounted one, yet have the power when I need it. Also the chances of both engines failing on the same day is slight.

Cringe away :)
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Sam,

I will hardly get to sleep tonight thinking about trim with that weight on the end, - try motorsailing, surprisingly effective even in light winds - but hopefully we'll all survive...

Clinging & cringeing on,

sj
 
stevensuf said:
usually there is only one side they can be laid on and normally its the side with the tiller face down ie tiller closest to ground
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That is correct
I think you will find the small Hondas are a notable exception to the rule.

Always read the manual.
 
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