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outboards

John Renton
We have to replace our ailing 2 stroke Johnson and I am not entirely sure whether we should be looking for a long or short shaft replacement. Our old engine mounted straight on to the transom never seemed deep enough in the water for maxmum efficiency. Am I right in thinking that a long shaft is recommended for the depth of transom on a sea hawk?  I just wonder whether the more bulky engine cover (on the newer engines) is going to impede the operation of the mainsheet if mounted directly on the transom and whether I would be better served with a short shaft and a drop down.  Do you have any advice?
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Re: outboards

GregSeaHawk
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This post was updated on .
Hi John,

Using an electric motor, I have little experience of petrol engines.

Long shaft is definitely the recommended type, as shown in the brochures printed between 1970 and 1986:
http://www.seahawk17.org.uk/promotion/brochurereedcraft1970.htm
http://www.seahawk17.org.uk/promotion/brochurereedcraft.htm
http://www.seahawk17.org.uk/promotion/brochuremore.htm

When it comes to swinging the engine forward to lift the prop clear of the water, a lifting bracket must be helpful, although to what extent that applies when using the Moore's style of main sheet (from centre of transom to boom) rather than the earlier "four-point" Reedcraft style:
http://www.seahawk17.org.uk/description/rigging.htm#mainsheet
I am not clear - and I know you use the Moore's style of main sheet.

For the effect that the added size of modern four-stroke engine has, I will have to turn to others for advice... (though a photo I have of your existing engine suggests that the engine cowling is quite large and a modern four-stroke may be no bigger.)
Greg Chapman
GregAfloat - My Boating Biography
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Re: outboards

ianhurley20
In reply to this post by John Renton
I have a Pirate 17 and have the same issue with mounting my Suzuki 4 stroke outboard. The prop is not really deep enough with a short shaft engine. The Seahawk transom is of a similar height above the waterline. My last boat had a rise and fall mount which put the prop in deeper and also enabled me to spin the engine to get reverse thrust, something I cannot do at the moment and also kept the engine away from any rigging.
As one of my winter mods I am in the process of mounting a rise and fall bracket, its certainly the solution for me.
Ian
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Re: outboards

Tom Altee
In reply to this post by John Renton
Long-shaft is my choice.  My experience with short-shafts is that if you are soloing and walk to the bow the prop lifts out of the water wind milling.  This is less of a problem if you are sailing with two and can have someone stay in the stern as a counter balance.