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
    Joined: Nov 2007
    Posts: 2,913
    Likes: 63, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    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
    Joined: Nov 2007
    Posts: 2,913
    Likes: 63, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    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
    Joined: Nov 2007
    Posts: 2,913
    Likes: 63, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

  7. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Wrong Shaft Drive Install

    Wear = drag and inefficiency
     
  8. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Twin U/V jonits are a CV joints just different build design.
     
  9. DCockey
    Joined: Oct 2009
    Posts: 4,923
    Likes: 455, Points: 83, Legacy Rep: 1485
    Location: Midcoast Maine

    DCockey Senior Member

    Not always. Sometimes wear can reduce drag until failure occurs.
     
  10. powerabout
    Joined: Nov 2007
    Posts: 2,913
    Likes: 63, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    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
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    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
    Joined: Oct 2009
    Posts: 4,923
    Likes: 455, Points: 83, Legacy Rep: 1485
    Location: Midcoast Maine

    DCockey Senior Member

    U joints and CV joints absob very, very little power.
     
  13. Landlubber
    Joined: Jun 2007
    Posts: 2,640
    Likes: 124, Points: 0, Legacy Rep: 1802
    Location: Brisbane

    Landlubber Senior Member

  14. TeddyDiver
    Joined: Dec 2007
    Posts: 2,580
    Likes: 123, Points: 73, Legacy Rep: 1650
    Location: Finland/Norway

    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
    Posts: 3,324
    Likes: 148, Points: 63, Legacy Rep: 1819
    Location: Adriatic sea

    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.
     

    Attached Files:

Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.