choosing prop size/ pitch

Discussion in 'Bubba's Outboards' started by riverdawg-1, Dec 3, 2008.

  1. riverdawg-1

    riverdawg-1 New Member

    Messages:
    738
    State:
    salem, va
    i have a 1999 50 hp johnson outboard, 2-cycle. it's on a 16 ft polarcraft bass america. i know the guy i bought it from changed the prop. my question is how do i decide the proper pitch for the prop if i replace it. i don't know which to get?
    thanks
    chip
     
  2. tofish

    tofish New Member

    Messages:
    3,923
    State:
    arizona
    best thing i can think of, is contact the boat company, see what it came from stock. then the motor people. then, a good, reputable prop shop and question them. let your fingures do the questioning. get answers from the sources.
    gary
     

  3. bulethed

    bulethed New Member

    Messages:
    82
    State:
    oklahoma
    the proper way to test your prop is run your boat fully loaded and trimmed into the wind and with a tachometer check your rpm,s. too high rpm means too slight of a pitch and too low means too much pitch and you are lugging the motor.........check with the maker of the engine and see what the top rpm is and go from there. the guy may have already propped it correctly and you just dont know it yet.

    the right prop is very crucial to long engine life.

    bill.
     
  4. flathead_hunter

    flathead_hunter Well-Known Member

    Messages:
    1,637
    State:
    nebraska city
    a good friend of mine is a certified mercury mechanic he told me it's about like putting puting gears in a rear end of a car... sometimes more is better sometimes less is better.. if you wanna go fast put higher gears in if you wanna come out of the hole hard at launch go lower i'm no super mechanic but thats how i understood it hope this helps any:cool2:
     
  5. Mac-b

    Mac-b Moderator Staff Member Supporting Member

    Messages:
    19,270
    State:
    North Caro
    Chip and anybody else, Google Turning Point Propellers, Inc. and fill out there list of questions and they will inform you what size prop you need for any kind of fishing boat. There is no charge to you for this service.
     
  6. PHLIPS4BIGKATS

    PHLIPS4BIGKATS New Member

    Messages:
    2,679
    State:
    Alma Kansas
    Thanks Mac. I checked it out but they don't offer my exact motor. It was either one bigger or one smaller. I have a 1988 mercurey 35hp oil injected, they show a 30 or 40hp.
     
  7. RRRKKK

    RRRKKK New Member

    Messages:
    68
    State:
    Quincy IL
    Well do a 30 then a 40 and split the difference