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quahog
08-12-2002, 06:37 AM
Presently I have a 9.9 hp '87 Evinrude on a Commander which barely fit in the engine well. When I first installed the motor , the back bottom of the engine cover rested on the back of the engine well. When the tilt pin was adjusted to clear, the bow was too high and the engine well filled with water. I raised the transom to achieve the proper engine tilt and clear the back of the engine cover.
I am presently looking at replacing the motor, but most of the of new motors have sleek engine covers that could interfere with the engine well. I don't want to go to a smaller motor, the 9.9 crawls in a big wind.
What new motors fits best? Is there a four stroke that fits?I saw an Ariel in the spring with a transom mounted engine, is this the solution?

Bill
08-12-2002, 08:30 AM
The outboard engine question is a recurring one on the board. You might want to review some of those past posts.

We don't recommend transom mounted engines. There are safety considerations in rough seas.

The sticky note dealing with computations (see tech) indicates that the minimum horsepower to drive the boat at max hull speed is 7.6.

An 8 hp 2-cycle Nissan (or similar) will easily fit the well, is light enough to reduce the difficulty of R&R. Four cycle engines are very nice, but anything over 5/6 hp will be too large to fit the well.

Mike Goodwin
08-12-2002, 11:51 AM
You also need to pay attention to the pitch of the prop .
This is a greatly misunderstood area of boating , too much pitch will load a diesel and make it blow black smoke, an outboard just won't rev .
Think of it like a bolt, a coarse thread will take up faster , a fine thread will tighten a heavier load with less effort.
Most outboards come with a "speed" prop meant for planing hulls .
I just dropped from a 8" to a 7" pitch and picked up a knot , I'm going to take the old 8" to the prop shop and have it changed to a 6" and keep the 7" as a spare .
I'm using a Nissan 6hp 4 stroke and got 6.4 MPH (not knots) on the GPS yesterday . The 6" prop should give me another 500rpms . I found the Nissan 6 to be the biggest 4 stroke that will fit in the well . The Nissan 8hp 2 stroke fits nicely.

quahog
08-12-2002, 02:59 PM
Thanks for the advice. My motor runs good for a '87 and I never had any problems other than a spun prop. It doesn't smoke at all with the standard 50:1 ratio. I use a 10X7 prop the lowest pitch I could find for that engine. I was hoping for a 4 stroke but I am not comfortable with a 6hp. I was a baymen for 10 years and know not to take mother nature for granted.

My next question is what length lower unit 20 or 25?

Mike Goodwin
08-12-2002, 04:11 PM
20" is fine , 15" will come out of the water in a good steep chop .

My grandad , who would be 115 if he was still around , used to say , " you don't need a motor if the wind is blowing "
He had a fleet of sailing oyster dredges 'skipjacks' and didn't switch to steam or diesel until the 1930's & kept sailing up to 1960 .
We used to sail right up to the dock .
I guess most folks are in too much of a hurry now days with a destination set in their mind and gotta get there come hell or high water ( actually , where I live , high water makes it easier .
I love swinging on the hook waiting for the tide to turn and the wind to fill in .
I found the Ariel to short tack quite well in a narrow channel .

quahog
08-12-2002, 05:01 PM
Thanks again. I have a 25" and was afraid of the prop sucking air in rough water with a 20".

I only use the motor to go down river in a south wind or up river in a north wind or when the wife is onboard. Although she enjoyed sailing to the dock on Sunday. She thinks we pissed off all the boat nicks. If there is no wind I stay home.

Mike Goodwin
08-12-2002, 07:37 PM
If you are sailing on Long island Sound , you got some fierce tide to contend with .And down near the city ain't no amount of motor going to get you thru Hells Gate if the tide is opposed .I been on 3000hp tugs that could only make a knot against that current .
I sailed through once on a full race C&C 40 , we stayed right beside a bouy for 45 minutes , knot meter said we were making 8.5 knots , GPS '0' .