Outboard for 23ft sailboat

[Brucet1988]

What is the minimum hp outboard I should consider for a 23ft sailboat?

[JKCatalina310]

Our old boat was a C&C 24 and had a 6 hp Johnson 4-stroke. That pushed the boat fine, comfortably at 5 kts.

[sailingdog]

Any reason for posting this twice?

[LakeSuperiorGeezer]

Three to four horsepower per ton. This is more than necessary to attain hull speed, but you could need the extra for headwinds and waves. If the boat weighs 3000 pounds, then figure 4.5 to 6 HP. If you want to calculate speed in knots, take the square root of the horsepower, multiply by 15 and divide by the beam. Say you have an Erickson 23 with a 7.9 foot beam and 4 HP engine, which gives 3.4 knots, but you should probably go with 6 horsepower for this 3200 pound boat in bad weather.

[tommays]

The formula is flawed in that outboard high thrust prop design has evolved to allow the motors to use there full HP at displacement speed

While i would not do it everyday i moved Seafever at 29' and well over 8000# over 16 miles to be hauled with a 4HP high thrust unit at 4.5 knots with a pretty dirty bottom


And on my J24 nothing above 4HP makes any difference in any weather

[LakeSuperiorGeezer]

The old rule of thumb I used was for inboard engines. Not sure why you should be so much faster. You might have been going downwind a little.

[cdhickey]

We've got an Evinrude 8hp 2 stroke on our 24' (3750 lbs), and it will push us all day at about 5 kts.

[dabnis]

Brucet,

I had a Coronado 25, about 4,500 lbs, i think. Started with a 6HP
2 stroke which was OK for calm conditions. Changed to a 15 HP
which was more than enough for the high head winds and steep chop
in San Francisco Bay. 6HP may be enough for your boat depending
on its weight and windage. Don't know what your sailing conditions
are or your motor mount configuration. If it is transom mounted,
suggest you get the longest shaft with a high thrust prop that will fit.
I think there may be very little weight difference between a 6HP
and an 8HP motor? In my opinion,FWIW, when things get nasty one
can never have too much power.

Dabnis

[mstern]

I have an 8hp two stroke on my Oday 23; it is adequate to push the boat at hull speed at about 2/3 throttle. My boat weighs about 3500 lbs, with equipment and a couple of passengers. The 8 hp replaced an older 9.9 two stroke, which was less efficient. Nowadays, if you are buying a new outboard, it will have to be a four stroke. You can probably use a 6 hp four stroke on a 23 footer.

[BlueWaterMD]

Had a Honda 8hp on my 23' and it pushed it 7.5 knots. If I had to do it over agoin I would go with the 6hp as it is more than enough power and there is a significant weight savings with the 6hp