my boat can not back off! very urgent!

Discussion in 'Sterndrives' started by susheng999, Jun 1, 2011.

  1. susheng999
    Joined: Jun 2009
    Posts: 10
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: CHANGZHOU CHINA

    susheng999 Junior Member

    the boat LOA:16.5m B:4m d:0.4m, displacement: 11t engine is mercury 130hp
    propeller is P15. NOW,when we drive this boat, going ahead is good.
    but can not back off,we can not feel the power. i think maybe the draft is very small. could you teach me how to settle this question? thank you very much!!!
     

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  2. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 475, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    A lot depends on the boat shape, the location of the outboard and any appendages there might be. Generally, if an outboard is setup properly, you have excellent control in reverse.

    Post a picture of the aft end of the boat with the engine lowered (out of the water of course).
     
  3. whitepointer23

    whitepointer23 Previous Member

    trying to pull up an 11 ton boat with a 130 outboard is going to be very difficult. you have a very small prop for a boat that size. what happens with outboards is they get a lot of airated water from the thru hub exhaust when in reverse, the heavier the load the more noticeable it is. this is why it goes well in forward and not reverse. have a look at a mercury yacht auxillary reverse mod. they use a prop which slides and has vents in the back of the hub. in forward the prop slides forward and performs as normal. in reverse the prop slides back and blocks exhaust outlet and directs exhaust through vents in back of hub. this way the prop always pulls in clean water.
     
  4. susheng999
    Joined: Jun 2009
    Posts: 10
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: CHANGZHOU CHINA

    susheng999 Junior Member

    thank you very much!
    i agree with you, the power is not enough, and the pitch is very small, now we will change big pitch and try to lower engine.
     
  5. whitepointer23

    whitepointer23 Previous Member

    if your thru prop exhaust is the problem. you have a sterndrive so you can change to a thru hull exhaust.
     

  6. susheng999
    Joined: Jun 2009
    Posts: 10
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: CHANGZHOU CHINA

    susheng999 Junior Member

    Now,it is better when we use big pitch prop. we will try to change the exhoust pipe if the space enough.
    A lot of Thanks for Whitepointer23 and PAR.
     
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