nose diving riveira

Discussion in 'Powerboats' started by aussiebrian, Feb 25, 2010.

  1. Oyster
    Joined: Feb 2006
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    Location: eastern United States

    Oyster Senior Member

    Then just like the position that I took early on, go back to the designed shaft setup, an easy fix, and work that out, one step at a time. The engine and its weight is located in the fattest part of the boat. Even if you move the engine back 10 inches, this amounts to almost nothing for trim, especially when sitting at the dock. Three hundred pound of balast did not cure the problem in its present setup. I don't think you are going to find that Velvet Drive unit. Its also possible that geographical differences creates a different lingo too. Gotta run....
  2. TollyWally
    Joined: Mar 2005
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    Location: Fox Island

    TollyWally Senior Member

    If it was me trying to figure out how to fix my boat I'd do 2 things.

    I'd place a tape measure running from the transom and record the centerlines of each component involved. Frames, mounts, flanges, rudder, struts, motor etc.

    Since this is a little boat and can be manhandled so to speak I would pull it out and place it on keel blocks. With a little judicial juggling you could find the existing center of balance without putting too much strain on the hull.

    Armed with this data I would begin anew trying to puzzle this out. I realize that others have already brought all this up in one fashion or another. I'm not saying this is a groundbreaking insight just what I would do. The guy is lucky there is a fleet of sisters from which to compare.
  3. Jango
    Joined: Aug 2005
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    Location: Mid Atlantic

    Jango Senior Enthusiast

    Correction to Post#63

    CG is 89 inches from Transom WITH DRIVER - 84.7 in W.O.
    Per Glen L Construction Plans - "Motor should be as FAR AFT AS POSIBLE"
  4. aussiebrian
    Joined: Feb 2010
    Posts: 11
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    Location: australia

    aussiebrian Junior Member

    Howdy all,
    appologies for neglecting my attendance, been building a kitchen. (that was the deal, i get a boat she gets a new kitchen).
    I have been reading all the comments and discussions and i'm not sure where to start.
    I managed to find a fellow sydney that has spent the last 40 years building and racing tunnel and mono hulls in local, state and national comps. He came out to view the boat in use, check dimensions/angles of the shaft, the engine and the location of fixed weights, seating position.
    guess what he said?
    "motors to far foward". So we have removed the motor and it is sitting on a pallet in the shed. Over the next month we will be relocating engine mounts, re-drilling a new shaft hole, plug all the holes we don't need and fitting a new engine hatch. It will be refitted 220mm further aft than its current location. the hulls centre of boyancey is "50mm aft of frame 3" according to Glen-l's reply (although this info is ommitted from the plans and spec's) we won't be able to get the motor exactly over this position, but as other builders have had success with this setup, we should as well.
    so i will sign off for a short time untill we finish and get back to everyone with our results.
  5. tunnels

    tunnels Previous Member

    I am so glad you havent fallen off the planet some where !
    As mentioned a couple of times id be looking for every mm to get the motor aft, so look at the rudder as well and see if you can possibly gain a few mils there as well .
    It its nose up its just a cav plate to bring it down but nose down is a complete differant kettle of fish .
    You have the motor out and the shaft and log so the rudder is just one more hole to attend to and plug up .
    I always ! draw it out full size and do all your measurments and calculations true to scale .
    Good luck and thank you for the up date !! theres a lot of people watching this particular posting , I know i am looking regularly every couple of days for anything new !!.
    :p :D
  6. GG
    Joined: Jan 2008
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    Location: MICH

    GG offshore artie

    Very nice ride i just might have to check out their kits.
  7. tunnels

    tunnels Previous Member

    Has anyone ever fitted a V6 to any of these boats ?could help to solve the motor too far forward problem , There must be some compatable hp equivlents to a V8 these days even if they are turbo'd !!:D
  8. GG
    Joined: Jan 2008
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    Location: MICH

    GG offshore artie

    Hey guys i am a little late to this thread and with everybody going back and forth about this and that has anybody even considered prop changes at all ?
  9. tunnels

    tunnels Previous Member

    You need to read all the posts!! Its been done !! :D :p
  10. GG
    Joined: Jan 2008
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    Location: MICH

    GG offshore artie

    Cool , i must have missed those posts .
  11. Typhoon
    Joined: Mar 2009
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    Location: Australia

    Typhoon Senior Member

    Brian, glad to see you have a plan of attack, look forward to seeing some photos of the boat being enjoyed soon!

    Regards, Andrew.
  12. Nova SS
    Joined: Mar 2010
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    Location: Bedrock, Ontario

    Nova SS Junior Member

    Glen-L doesnt really offer frame kits anymore. They decided a few years back to get out of them when their shop formen retired. Now with that said they do have some on hand, possibly for this boat i dont know, but when they're gone they're gone.
  13. kach22i
    Joined: Feb 2005
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    Location: Michigan

    kach22i Architect

    220 millimeters = 8.66141732 inches

    It is a handsome design, please post more photos when all is well.
  14. tunnels

    tunnels Previous Member

    How is progress with the nose down thingie ?
    Have been keep a eye out but not seen anything posted since the mad rush a while back .
    Would like to see the end result and what you had to do to fix it !
    Good luck ! May be out of sight but not forgotten !:p

  15. aussiebrian
    Joined: Feb 2010
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    Location: australia

    aussiebrian Junior Member

    howdy tunnels,

    I'm workin' on it but I'm self employed and have been busy searching for school fees, mortgage payments and dog food, apparently there more important.

    I haven't done much since my last posting. we have removed the motor, re-drilled the shaft hole in the new location (managed to get the prop back 235mm) and that's where we ground to a stop.
    While I had the motor out I had the sump plug re-located to the side and a drain tube fitted for easier access and we had to get a new prop shaft, some how it has been bent in the last 180mm where the prop fitted on.
    the replacement parts should be ready next week and we can get stuck into it again.

    best regards,
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