Wrong Shaft Drive Install.

Discussion in 'Inboards' started by tom kane, Mar 11, 2013.

  1. tunnels

    tunnels Previous Member

    Have done it many times and never had any problems ever !! not one !!
    :)
     
  2. powerabout
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    powerabout Senior Member

    now explain to the readers what the difference is between a CV joint and a std uni joint.
     
  3. tunnels

    tunnels Previous Member

    why ?? theres very little to explain !!
    i was bought up before cv joints were thought of or became the rage and the only thing people would even consider using these days !!
    We used to make a plates made to fit in the middle OF the flywheel and use small truck universal joints that bolted to the flange on the back of the gear box with the spline and sliding joint at the other end and machine fit a weld a flange to the sliding joint part and a split flange with a keyway to the prop shaft then clamp it and that was our lot !! About now you will be saying it wont work !! sorry but it did ! :eek:
    These were the days of flat head v8 mercury motors when engineers could make anything !! My father was a wizz and i watched and did the same things myself on boats i made myself and like i said never had a problem ever !!.
    One boat i made my own Vee drive and used a car drive saft and cut it to length and re welded the tube to the flange again so it had two universal joints one at each end !!
    What is the trick doing that kind of a cut and reweld ??come on smarty pants !!
     
  4. powerabout
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    powerabout Senior Member

    2 unis, yes that will work smoothly assuming you aligned/phased them correctly
     
  5. tunnels

    tunnels Previous Member

    HOW do you align them ?? in what way !!:confused:
     
  6. powerabout
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    powerabout Senior Member

  7. tom kane
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    tom kane Senior Member

    Wrong Shaft Drive Install

    Wear = drag and inefficiency
     
  8. tom kane
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    tom kane Senior Member

    Twin U/V jonits are a CV joints just different build design.
     
  9. DCockey
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    DCockey Senior Member

    Not always. Sometimes wear can reduce drag until failure occurs.
     
  10. powerabout
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    powerabout Senior Member

    I'd say if you want zero loss run the uni joints with zero offset, they wont last but they wont absorb any power either.
    I agree Tom, 2 uni joints are there to create a CV effect ( assuming they are set up correctly)
     
  11. tom kane
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    tom kane Senior Member

    Wrong Shaft Drive Install

    C/V`s need off set just like twin U/V` with sliding spline.Twin U/V`s is a C/V joint. For longer service and less vib`s.

    Google constant velocity joints Images and see different designs
     
    Last edited: Mar 23, 2013
  12. DCockey
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    DCockey Senior Member

    U joints and CV joints absob very, very little power.
     
  13. Landlubber
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    Landlubber Senior Member

  14. TeddyDiver
    Joined: Dec 2007
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    TeddyDiver Gollywobbler

    Concur with LL..
    and Tom, U joint is never a CV joint. CV means constant velocity und universal joint doesn't work that way.
    BR Teddy
     

  15. CDK
    Joined: Aug 2007
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    CDK retired engineer

    The simplest and probably cheapest solution is this double joint from Spicer, designed to couple a jet pump to a GM 350 engine. It can handle several 100's HP, behaves like a CV joint and requires little -if any- maintenance.
    It is true that a 0 degrees angle is bad for such joints, but in that case you don't need it and better use two flanges with a rubber disc between them.

    A CV joint is happy with an angle of only 1 degree. All you need to do is try to line up the engine as well as you can without using a laser or other equipment, the error will be 1-3 degrees if your eyesight is good, considerably more if you squint like Marty Feldman.
     

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