Hezi wrote:
Hi Walt, I know you have the Suzuki. The long shaft is available now and it's adding only 5" . I know the short shaft would work, but with consideration to a rougher sea, my concern was for the motor to get splashed or momentarily submerge which will turn it into dead weight. I thought longer shaft will put the motor higher and more protected from waves. This will also raise the center of gravity but with the amas it will have no impact. Am I over complicating this? I am buying this new and want to make the right decision... Another idea I had, and before I am getting into even considering it, was to create an aluminum frame, light and strong and position the motor behind the rudder. This will take the noise farther to the back and turn the ride more pleasant. The location will be superior in terms of geometry (I believe), the con is more weight on the back. With that position, it'll be like a leverage on the back and I'm afraid will lower the rear below rudder lines. I am in the process of installing auto electric bilge pump, so I am not overly concerned with water sipping in. What do you think?
You raise some interesting issues.
I do not believe adding 5" on shaft length would really offer any advantages. I have had spray go three feet aver my head (true!) so raising the motor a few inches will do little to help, given that you only need the prop to be a few inches under water (we are not talking about a water skiing application here!)and even a short shaft motor raises the head high enough as stringy mentions. However, most outboards have a cowling which will protect the motor unless it is virtually submerged, so airborne spray will not be a problem. While I also agree that a longer motor will have little effect on stability, frankly, I reckon it would look a bit dorky sticking up higher
Given the beam of the Island, positioning the motor on one side creates zero noticeable asymmetric thrust. Furthermore, hanging the motor way out back is going to tend to make the ride worse (ideally any sailboat works best with all weight located in the centre), while greatly increasing the possibility of the motor getting dunked in big waves, or else, in the same conditions, waving the prop in the air.I have noticed that the long and flat shape of the Island can mean that either end can be well submerged in waves (luckily only very temporarily), and anything which further increases the length is going to magnify this trend.
As for noise, my motor is a cheap and loud 2 stroke, and I have it mounted almost literally under my elbow. The exhaust leaves the motor at prop level, and the noise is quite bearable. Remember also that it is a sailboat, so running the motor will be an exception, rather than the rule. To be honest, I do not think that moving a motor a few feet is going to make that much difference to "nuisance" level.
Lastly, I would never modify the Island in a way that puts hull openings under water, and then rely on a bilge pump to avoid the consequences... far better to avoid the problem in the first place.
In summary, I would suggest a short shaft motor, and mount it anywhere which is convenient (remember that these small motors use a starting cord and manual tilt - and might need refueling while at sea). My "centre-mount" is unconventional, but necessitated due to my being a fat bastard whose weight in the rear seat was not ever going to work,. but access to the motor meant that a (more) rear mount was impractical.
Hope these thoughts help!