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Old 12-11-2012
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Re: Could 27 hp fit here?

Quote:
Originally Posted by L124C View Post
Started another more general thread about the boat, and the consensus among most owners of sister ships seemed to be the motor would be a little light, and that the 28 would have fit. Looking at a Alberg 35
If I decide to make an offer, it would be contingent on a sea trial and survey. Just trying to qualify it now. In addition to the boats lineage, the new motor was the strongest thing going for it, so sufficient power became the issue.
Now I'm wondering, what if conditions are benign during the sea trial? How do you really test for sufficient power? My biggest concern is not so much at sea (though that is certainly important), as handling in tight situations like a marina. For example, the boat might slide into her slip and stop on a dime on a windless day without current. However, how about with a 20 Knot tail wind. If the boat was bristol and slightly underpowered it would be one thing. However, I've got a lot of work to bring this old girl back to life, so it's important she's got the right motor, especially since it's new. Anyway, back on topic, seems the owner tried to save a grand and went with a light motor, as I suspected. How do I test it on a flat water day with no current/wind?
For starters you could run a course with a GPS and compare it with the projected hull speed, taking into account how dirty the bottom and/or prop is.

After that you could tow something like a small drogue to try to simulate head wind and/or heavy chop and see how much the speed drops off. If that cuts the towing speed a lot, maybe by a third or half, maybe it doesn't have as much thrust as you want. Perhaps comparing the numbers to your previous boat might give you a starting point.

Not very scientific, but it would be a place to start

Paul T
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