outboard for a strawler

Discussion in 'Outboards' started by Chuck Losness, Aug 29, 2022.

  1. Chuck Losness
    Joined: Apr 2008
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    Location: Central CA

    Chuck Losness Senior Member

    If I ever sell my 37' gulfstar I plan to go to a 23" to 25" trailer sailer that will be converted to power only. Probably an Aquarius 23. Original thought was to use something like a Yamaha 9.9 high thrust outboard for power. This would be way over kill for normal usage and place a lot of weight on the stern but would have a lot of backup power for rough weather.

    A Tohatsu 6hp sailboat outboard would be a better choice for most conditions. Would probably have to run it at close to max rpm in rough weather.

    Speed is not an issue. It is a displacement boat. Top speed probably 5 to 6 knots. Maybe 7 knots under ideal conditions. I plan to primarily cruise all over So Cal including the Channel Islands. California Delta, Puget Sound and the Sea of Cortez are also possible cruising destinations.

    I never like to run any motor at anything close to max rpm. So would I be better off with the bigger outboard running at a lower rpm verses a 6hp at a higher rpm?
     
  2. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    In a nutshell, all else being equal, yes, you should generally get better fuel economy by running the bigger engine at less revs.
    .
    You say that the Yamaha 9.9 hp motor would place a lot of weight at the stern, compared to the 6 hp Tohatsu - what is the difference in weight between these two motors? Compare this difference with the weight of yourself and your crew in the cockpit.
     
  3. Chuck Losness
    Joined: Apr 2008
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    Chuck Losness Senior Member

    No crew. I am a singlehander.

    My recollection was the 9.9 weighed over 100 lbs compared to the 6 at around 55 lbs. Checked the weight of the 9.9 and it is around 90 lbs depending on the configuration. So looking at a 35 lb weigh difference. They only give fuel consumption at max rpm. 9.9 at 1.1 gph verses the 6 at .5 gph. These are just general numbers on fuel consumption. Different sites give different numbers.

    Another consideration is theft. The 9.9 will push a panga whereas a 6 won't. This would be an issue in Mexico.
     
  4. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    A 35 lb weight difference in the grand scheme of things is not going to be significant really.
    Are you the stereotype 180 lbs gent, or do you weigh a bit more (say 35 lbs more?)

    This sounds like it could well be a more important consideration! :)
     
  5. Chuck Losness
    Joined: Apr 2008
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    Location: Central CA

    Chuck Losness Senior Member

    I haven't weighed 180 lbs since I was in high school. A little north of 200 these days. I am thinking of using "stick steering." Stick steering would keep me out of the stern.

    I recently bought a 1986 Randall 14' skiff to use on the lake where I live. It has stick steering. There is a stainless steel bar that moves the steering cable. Push the bar forward and the boat turns to the right. Pull it back and the boat turns to the left. The skiff has a 25 hp outboard. The seller said it works really smooth. The skiff had been in his family since new. He inherited from his grandfather 25 years ago. I haven't tried it out yet. Water level is too low to launch boats.

    Outboard theft is an issue in Mexico. That's why I never had an outboard over 8 hp when I was cruising in Mexico. And lifted my dinghy out of the water every night.
     
  6. ondarvr
    Joined: Dec 2005
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    Location: Monroe WA

    ondarvr Senior Member

    Those are very different motors, they’re not even close in picking one for this application.

    The Tohatsu is a crude single cylinder vibrating and loud annoyance on a transom.

    The 9.9 Yamaha is a very quiet, smooth and much more modern design.

    The Tohatsu would be adequate as a seldom used backup, or something to get you around the marina. It’s not a motor you’d want to use for cruising around for an extended period of time.
     
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  7. Chuck Losness
    Joined: Apr 2008
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    Location: Central CA

    Chuck Losness Senior Member

    I know the two are very different outboards. I picked the Tohatsu as an example because it has a high thrust model for sailboats. Decades ago I had a 3.5 hp Tohatsu on a dinghy. That was one great little outboard for a dinghy. Wish I still had it.
     
  8. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    Do not go super small hp. On a 23' boat; you won't have a big enough prop to run in a head sea and will fight for control.
     
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  9. ondarvr
    Joined: Dec 2005
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    Location: Monroe WA

    ondarvr Senior Member

    I've had both, the Merc/Tohastu was rarely used.
     
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