Last Outboard Thread - Does My Dream Outboard Exist?

Discussion in 'Propulsion' started by CatBuilder, Feb 11, 2012.

  1. CatBuilder

    CatBuilder Previous Member

    Thank you everyone who participated in the "ganging outboards" thread. It was a huge success and I have settled on gasoline/petrol outboards, mounted like Richard showed in the final couple posts on that thread.

    It is going to be gasoline/petrol unless there is a real diesel outboard out there that is in production from a reputable manufacturer.

    Again, thank you.

    Now, since I am busy building a boat, I wanted to "crowd source" the exact outboard to purchase.

    I have a dream outboard, but nothing seem to have all the features. Could anyone suggest an outboard model or models that will come close to these "wants?"

    *Pair of 30HP outboards - *OR* - 60HP and 9.9HP

    *25 inches, 63.5cm shaft or longer
    *Large Diameter Displacement Boat Prop like Yamaha "Dual Thrust" Prop
    *3:1 gear ratio (or similar to work with prop as above)
    *Fuel Injection (no carburetor)
    *Power Tilt Function
    *Electric Start

    *All, including power tilt should be able to be controlled from remote control station with Morse type controls - can be 2 separate controls mounted next to each other.

    Does anyone know of a brand and model of outboard that will fit these dreams?
     
  2. michael pierzga
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    michael pierzga Senior Member

    What outboard will you use for your tender ? Redundancy would be nice.

    The only common , mid size , 25 inch outboard I know of is the honda 50hp . Its possible there are others, you would have to speak with an outboard guy.

    And this HIGH THRUST ? is it necessary ? Only a few outboards seem to be marketed as High thrust. What is high thrust ? only a gear ratio modification or is the engines electronic management High thrust programmed ?
     
  3. rasorinc
    Joined: Nov 2007
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    rasorinc Senior Member

    Yamaha and Honda high thrust engines have a gearing of 2.33/1 Any further assistance would be by the correct prop.
     
  4. WestVanHan
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    WestVanHan Not a Senior Member

  5. Submarine Tom

    Submarine Tom Previous Member

    Buy whatever brand has the best customer service in your area. This may not seem so important now but after you've paid for them, it suddenly becomes the most important thing and for a long time. I speak from experience...

    -Tom
     
  6. rasorinc
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    rasorinc Senior Member

  7. masalai
    Joined: Oct 2007
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    masalai masalai

    Hi Catbuilder,
    We seem to be getting down to the "nitty-gritty" of the selection criteria - I also had a good look around for diesels and only found the Yamnar 27hp diesel which I suspect, is no longer manufactured - even a reconditioned one lacks in key areas - gear ratio not low enough as in my mind the ideal propeller rpm is 1000 to 1200 rpm maximum and the propeller needs to be at least 15" diameter... and http://www.minardsdiesel.com/outboard.htm as the only source of recond was not able to meet those criteria... Critical for a displacement only operating boat...

    I have posted mainly in the hope that something arises that I could appreciate and consider -
    - around 27hp,
    - electric start and
    - remote tilt,
    - diesel,
    - low geared propeller rotational speed up to 1000 or 1200 rpm,
    - 15 inch dia propeller or larger (steering is optional as I do not want engine steer) , and
    - a LONG leg...

    I wish you every success and pray for your good fortune...
     
  8. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    The "high thrust" is simply the result of using a bigger lower unit off a higher hp motor, and changing the gear ratio to higher reduction. That enables a larger diameter prop to be used than a smaller lower unit could accomodate.
     
  9. waikikin
    Joined: Jan 2006
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    Location: Australia

    waikikin Senior Member

    Seems like a pretty valid scheme to match the tender OB with the cat propulsion out boards.
     
  10. CatBuilder

    CatBuilder Previous Member

    While absorbing all of the different input (thank you, everyone), I did want to mention that I can't match the outboard for the tender with the outboards used to propel the cat.

    Two entirely different applications with entirely different outboards required.

    Getting a 45' catamaran to move along in the high single digits is a very different story from getting a 12' inflatable RIB to move along at 12 knots or more planing.

    Two entirely different outboard and props.
     
  11. masalai
    Joined: Oct 2007
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    masalai masalai

    Hi CatBuilder,
    I wholeheartedly agree, That diesel Yanmar came close but gearing ?? and limited propeller size - - What the heck were Yanmar thinking when they brought it out... A beautiful opportunity at making a great and useful mark for the boating fraternity - SPOILED by stupidity and ignorance....

    I have posted mainly in the hope that something arises that I could appreciate and consider -
    - around 27hp,
    - electric start and
    - remote tilt,
    - diesel,
    - low geared propeller rotational speed up to 1000 or 1200 rpm,
    - 15 inch dia propeller or larger (steering is optional as I do not want engine steer) , and
    - a LONG leg...

    Manufacturers where are you? - - The Asian market has gone to "longtails" and home made - could have been HUGE for a well equipped diesel-O.B....... SWAT analysis not done was it? . . . That same lazy 'bathplug' is probably playing - asset stripping - instead of - making something worthwhile and useful.....
     
  12. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Who makes diesels with alloy blocks ? That would seem the first requirement for an outboard, or would sink the stern ! The Yanmar was an old leg style, and as has been said, not big enough prop for slower, heavier boats. And there was a guy here who said he worked for a fish farm operation who had a number of them, and they had a mechanic working full time to keep them running ! That sounds ridiculous, or it was a very big operation, but it is not encouraging. And if they were a top unit, the next question is why no more being made ?
     
  13. masalai
    Joined: Oct 2007
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    Location: cruising, Australia

    masalai masalai

    Rover V8, - - BLMC-P76, (both petrol) - and the new VW inline 5 cylinder diesel - - Current 2litre golf 2litre diesel is alloy block (ie golf5) - - the 75 hp 3 cyl turbocharged mercedes diesel made in USA for the 2+2 smart car and used in the Ramphos trike http://www.youtube.com/watch?v=8nmqrNe3DIc&feature=fvwrel but Mercedes is very unhelpful... and this :eek: from ww1? Germany http://www.billzilla.org/ideas4.htm WW2 Junkers opposed piston diesel aero engine, :eek: - - to start,

    http://en.wikipedia.org/wiki/Volkswagen_Lupo with 3 diesel engine options in the comparative chart... - - Which ever engine choice, one must dry sump and modify to run with the crank shaft vertical - a big ask, then fit heat exchanger for fresh water cooling or have manufactured in an alloy that is "salt water tolerant.... Then fit an appropriate leg, mate all the bits - OH BROTHER - when did you need those outboards?

    Another brand that I nearly used - Lombardini - http://boatdiesel.com/Engines/Lombardini/Lombardini.cfm
    http://www.lombardinimarine.it/prodotti_dettaglio.aspx?type=mtr&pnl=foto&mtr=ldw1404sd - - - - - - - - 1372cc 4 cyl 40hp saildrive at 160kg
    http://www.lombardinimarine.it/prodotti_dettaglio.aspx?type=mtr&pnl=foto&mtr=ldw1904sd_50 - - - - - 1995cc 4 cyl 50hp saildrive at 257kg
    http://www.lombardinimarine.it/prodotti_dettaglio.aspx?type=mtr&pnl=foto&mtr=ldw1003sd - - - - - - - 1028cc, 3 cyl 30hp saildrive at 141 kg...

    I settled for Kubota/Nanni as I knew I could get spare parts in the S.W. Pacific region... both use the same 17 spline propeller shaft... as appears to be common in most saildrives...
     
  14. waikikin
    Joined: Jan 2006
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    waikikin Senior Member

    Here you go Mas, just scale this http://www.schottel.de/fileadmin/data/pdf/eng/eng_NAV.pdf down & corner the market. Of course I'm just going to accept the compromises of the readily available petrol outboards.

    Catbuilder, I think you already know the answer to the question posted that no outboard ticks all those boxes, the Honda 20 hp xtra long comes close but a bit low on power & prop/gearing for the windage etc of your vessel, gunna suit mine fine though.
    All the best from Jeff.
     

  15. CatBuilder

    CatBuilder Previous Member

    Yes, Jeff. I was just asking which outboard model currently made comes closest to that ideal outboard.
     
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