Question about prop

Discussion in 'S2' started by Will423, May 20, 2019. Add this thread to a FAQ

  1. Will423


    Joined May 20, 2019
    4 posts, 1 likes
    S2 9.2
    Will Ingram Us In Northeast
    I just bought my first sail boat, it’s a 1981 S2 9.2 with the 15hp yanmar (2GM). It’s in great shape overall, I’ve been extremely lucky for her age. I have been told by a few people that the only issue is that it’s under powered...(can’t fix that now) but also was told that the 2 blade prop is not as effective as a 3 blade. I’ve found that the YGM can have either the 14x11 or the 15x9 on 3 blade. I guess my question is mostly about practicality, I was told that the 3 blade makes it more manageable and maneuverable under power. Does it make a difference really? If it does is the shaft 1”? Or 1 1/8” I didn’t have my caliper when I was at her last, but to my eye it’s at least 1”. I would be able to do this on my own but my tools at school are in Rhode Island, I live in Mass, and the boat is on the hard in Conn, and I drive a 2 it’s hard to have everything I need when I’m going between all of that. Any info I can receive would be greatly appreciated.

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    Last edited: May 20, 2019
  2. LeeandRick


    Joined Apr 26, 2015
    447 posts, 160 likes
    S2 26 Mid
    US On Trailer

  3. jssailem


    Joined Oct 22, 2014
    9,335 posts, 4,159 likes
    CAL 35 Cruiser
    US Salem, Moored Port Everett WA
    @Will423 It appears that you are Thinking about a propeller change.
    The first question is how do you want to use your boat?
    • If sailing perhaps racing is the dominate use then a 2 blade prop is going to give you improved sailing experience. With the blade in line with the keel you got reduced prop drag which means improved sailing speed.
    • If you are doing a lot of power cruising with conditions of high currents or expecting to frequently be in heavy weather conditions under power then perhaps a 3 bladed prop can provide a little improvement under power but you will sacrifice sailing speed.
    Boats are a series of compromises. Only you can decide which side to favor and which to give up.

    An additional option is a folding or feathering prop. This will mitigate some of the limits of the fixed blade prop. These come with a price tag.

    It is your boat and your choice. Choose wisely.

    Justin_NSA likes this.
  4. Will423


    Joined May 20, 2019
    4 posts, 1 likes
    S2 9.2
    Will Ingram Us In Northeast
    Thank you for the input. The boat has a fixed 2 blade prop already. So from what I’ve been told there shouldn’t be much more drag with the 3 vs the 2. A feathered prop is not an option for me right now, but a 3 blade is for nothing. I will be doing quite a bit of motoring when I take her from Newport down the Eastern Seaboard. I may change it later but I’m thinking the extra control during my trip down will be worth it. Again thank you for the input.

    jssailem likes this.
  5. Scot Yount

    Scot Yount

    Joined Nov 10, 2018
    13 posts, 1 likes
    S2 9.2a
    US Marblehead, Massachusetts
    Congrats on the boat. I am in Marblehead and there are not too many S2s around...Mine is my first boat too. Would love to know how you make out with the prop.

  6. Will423


    Joined May 20, 2019
    4 posts, 1 likes
    S2 9.2
    Will Ingram Us In Northeast
    I went to her a few days ago, the prop I was given would’ve worked, but I just didn’t have the materials I needed to get it off, it’s launching in 2 weeks so I’m concentrating on other things. My problem is that I’m Newport, Rhode Island going to IYRS, I currently live aboard a boat in Massachusetts, and my boat is at a Marina in Connecticut. I have a small 2 seater car so it’s difficult to get everything I need when I’m driving 2 hours to get to her. Once she’s launched she will be right in the harbor next to my school so I’ll have all my tools and more close. I love the boat though. Thanks

  7. BobM


    Joined Jun 10, 2004
    3,258 posts, 12 likes
    S2 9.2A
    US Winthrop, MA
    Been there and got that tee shirt. My boat was in Milford CT when I bought it. I trucked back and forth for weeks doing a bunch of stuff that people "thought I should do", but at least I had a pickup truck!

  8. Will423


    Joined May 20, 2019
    4 posts, 1 likes
    S2 9.2
    Will Ingram Us In Northeast
    When I get settled in Mobile I’ll be buying a truck for work..but right now I’m just trying to “stay afloat” figuratively...and hopefully never literally

  9. Tally Ho

    Tally Ho

    Joined Jan 7, 2011
    1,362 posts, 288 likes
    Oday 322
    US East Chicago, IN
    I have had the 2GM20F Yanmar in my last 2 boats...1990 Hunter 280 and my current 1988 O’Day 322.

    I am on Lake Michigan, so I don’t have to fight any currents, but I find the engine pushes the boat ok. I run a fixed 2-blade prop and it pushes the boat at 6+ knots pretty easily.


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