Sweet spot .. found !

Discussion in 'Bubba's Outboards' started by Pogo, Jun 18, 2006.

  1. Pogo

    Pogo New Member

    North Carolina
    This is mostly a FYI (For Your Information) post and not a problem ... not now, anyway.

    As several of you know, I recently completed rebulding a 1981 Polarkraft (original name) 14 footer .. the first of it's type I've ever owned ... that had been wrecked while being towed on the trailer.

    Over the past several days, I've played with engine placement settings ... interesting, but not a lot of fun.

    All my prevous experience is with bigger boats, all of which were either Deep-Vee or Semi-Vee heavy water boats .. this wee critter with it's flat transom and hard chine has proven to be a whole new experience for me.

    First, I started off with the manual settings of the cav plate about 1 to 1 1/2" below the transom with the engine full down (gotta start somewhere and down makes more sense than up) ... o.k performance, but the rig didn't seem happy. I know that sounds like trash, but it's true .. these things sound right and run right when they are happy .. otherwise, they run, but you can tell there's more in there.

    Next, I raised the engine 1" ... better running and more top speed, but water was thown as much to the side as behind the rig.

    Next run was with the engine at the same height , but angled up one notch from full down (only change one thing at a time) ... bear in mind that in the very bottom hole (full under), it planed wonderfully and quickly. Up one notch gave no apparent loss in performance, a bit less water side throw, but .. something still not just right.

    O.K. ... leave the angle on the transom and raise the engine 1/2" ... :smile2:
    You're looking at one happy camper.

    From DIW, smoothly rolling on full throttle brings the bow way up, then within 2 seconds, her bow starts lowering and she sets at a sort of plane for a couple seconds then lowers further to the horizon and plain SCOOTS!!!

    The point of all this is (for any who are interested and still reading this)... no two boat/engine combinations are alike ... you can go by the manual and get good, safe performance. To locate the "Sweet Spot" where your engine and boat work together as one system to give you the best of both hull and engine takes time, trial and error and patience.

    I rebuilt her from utter trash and now I like her as much as any I've owned.
  2. catseeman

    catseeman New Member

    Indianapolis, Indiana
    congrats ,i lked your thead

  3. Bubbakat

    Bubbakat New Member

    Larry that was a well written and detailed post and I have to agree with you. It ain't as much the hearing the motor hit the sweet spot it is to me more like a feeling.
    But you are right when a motor is running right and you have her dialed in on the boat right , it just sounds and feels happy.
    Like I said good post and thanks for the report.
  4. Pogo

    Pogo New Member

    North Carolina
    Thank you both for your comments ... I'm glad you enjoyed reading the post.

    I was reluctant, at first, to post that, but I see so many questions related to "set up" that I figured a "back to basics" recounting of a real life experience of starting from scratch and changing one thing at a time wouldn't hurt.

    It takes time, sure, and several test runs, but the end result is surely worth it. Plus ... :smile2: ... even during testing, you're still out there in Mother Nature's back yard and on the water ... tough to complain about that.

    Yeah, Bubba ... maybe it's an acquired thing, but once you hear/feel a mechanical system running sweet ... you'll know it again when it happens.

    I've seen it in airplanes, boats, motorcycles and cars and it's the same in each ... you don't have to look at the guages, but if you do, the needles will be pointing to just where they should be. I know there isn't a living cell anywhere, in any part, but, I swear, they talk to you and tell you when they are happy.