twin engine mount

Discussion in 'Stability' started by timo, Mar 3, 2011.

  1. timo
    Joined: Feb 2011
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    Location: Cape Town

    timo Junior Member

    Ok Fanie. Ill get some pics;) .
    I seriously have a low budget, otherwise I would buy a different boat. The engines have no hydrolic trim/tilt function but I find I get buy without it(I would love to have power trim and i'll probly try fit it if it's viable).

    Generally the boat goes very well- but you must know how a small niggly thing can be vexing and can bend your mind to it.
    I can't think of any reason for engine mount position except to increase the distance to avoid cavitation as I've been told is a fallacy by Gonzo.
    (I have no cavitation issues - I just thought that was why the engines were spread further apart)
    A jet drive is definately not something I have money for. Neither is replacing my engines a financially viable or necessary option.
    Cavitation (again) is not really an issue.
    A sheild for the kelp will work.

    I pull out the bung after I've gone out. not even a tea spoon of water comes out - There is a screw in the deck at the battery box that leaks a little. So Im not particularly fussed.

    As I said, I think the problem may be with the hull - as i discovered that the starboard flange holding the pontoon is 20mm lower than the other side at the transom. You will see in the pics clearly that one tube is lower than the other.

    Wynand, Im aware of the drawbacks of twin engines - however they are my preference and they are what I have. I have already said.

    There is a difference between a flat bottomed bass boat on a piece of land locked water and a sea going boat on the ocean.

    If I had the choice to limp back on a single 40 or a 2HP I would choose the 40

    Maybe when I buy my next boat I'll keep that in mind.

    I stand corrected about Cat. D 5NM.
     
  2. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    There is a bit of a musunderstanding wrt this. Some of the fresh waters can become a nightmare, same as the sea. I won't be surprised if Bloemhof dam capsizes more skiboats than any launch at sea.

    Have a look at Wynand's website... see the boats he built.

    That is not really any indication - if the boat is filled with the polyurithane pour foam it may be the problem. The foam will absorb water and the boat will become heavier and heavier over time. That foam is famous for letting water in and not out. The foam is used only because it is easy to get it in the boat as an after market solution for flotation. Few boats not factory fitted with the foam gets prepared properly for it to offer long term water resistant service.

    The least the foam guys should do is to let their customers know there is such a problem so they can weigh the boats and notice any change in weight over time.
     
  3. timo
    Joined: Feb 2011
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    Location: Cape Town

    timo Junior Member

    Ok, but as far as know a RIB under a certain size does not need to be filled with foam to attain a buoyancy certificate? Im sure my boat is not foam filled. I have a buoyancy certificate.
     
  4. timo
    Joined: Feb 2011
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    Location: Cape Town

    timo Junior Member

    I can't access Wynand's website
     
  5. Wynand N
    Joined: Oct 2004
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    Location: South Africa

    Wynand N Retired Steelboatbuilder

    Timo,
    Seems there is a problem with the server but I already asked my friend who had set it up originally to investigate. Hopefully would be back on line soon.

    Update: Server hard drive failed. Backups currently being loaded of all sites, mine included and should hopefully be up and running by the weekend. Sorry for any inconvenience caused because of this..
     
    Last edited: Mar 10, 2011
  6. timo
    Joined: Feb 2011
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    Location: Cape Town

    timo Junior Member

    Hi, I took photo's but I have forgotten them at home. I'll post them tomorrow. Thanks Wynand - I still can't access the site, Ill try again tomorrow.
     
  7. timo
    Joined: Feb 2011
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    Location: Cape Town

    timo Junior Member

    I posted up the pic. You can clearly see the pontoon is scew, althogh it's not so obvious looking from the front/side or close up. I'm not sure there is a solution. The boat was repontooned - I've asked the guy that did it - he said that they use one side as the pattern for the new pontoons and simply mirror it. The flange supporting the pontoon is skew.
    The other pic is a close up on the splice - you will also see another reason for my wanting to replace it (although not critical its not aesthetic).
     

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  8. pistnbroke
    Joined: Jan 2009
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    Location: Noosa.Australia where god kissed the earth.

    pistnbroke I try

    maybe a bit stupid here but is it not that the two sponson tubes are identical but have not been rotated to match.Normally the downward pointing cones on the end of the sponson are at the bottom ....these dont seem to match/not symetrical .or are you saying he whole Rigid bit of RIB is twisted ?.the motors look spaced fine .and the props deep enough ....get them any closer and you wont have room to work on them
     

  9. timo
    Joined: Feb 2011
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    Location: Cape Town

    timo Junior Member

    Possibly - It does look like the left cone is upside down. But one pontoon is definately lower than the other. The hull is not twisted. It's just the flange supporting the pontoon. It's somehow skew/ at a steeper angle to the opposite side. The cones project quite far from the transom so the difference is accentuated by the angle.
     
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