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Results 1 to 8 of 8
  1. #1
    Join Date
    Aug 2016
    Location
    Holland, Michigan
    Posts
    45

    Default SunTracker pontoon with Mercury 40 hp.?

    I have a 2002 Sun Tracker 21 ft. Pontoon w/ MERCURY 40hp.
    2-stroke. Two cylinder. I have a MERCURY Black Max prop
    that is 12 1/2" X 9" (3 blade).....the top of the blades are the
    same height as the bottom of the two toons.
    I only get 4900 rpm's and 13 mph....and when it hits 4900 rpm
    the prop blows out.
    ANY SUGGESTIONS on the next prop???
    (I'd like 5500 rpm with 15> mph.)

  2. #2
    Join Date
    Dec 2015
    Location
    maplevalley WA
    Posts
    3,469

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    How many splines on the propshaft? Possibly drill some holes in the prop so it ventilates you may gain some RPM. A prop with less pitch and cupped is another possibility. Thats a big boat for a 40hp if you want faster your best option is a bigger Engine.
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  3. #3
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    13,649

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    Perhaps a small atomic bomb will make it fo faster ?

  4. #4
    Join Date
    Aug 2016
    Location
    Holland, Michigan
    Posts
    45

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    It's a 13 spline !?
    im ok with the 13 mph...I've had 16mph a few times.(just right conditions
    and set up I guess).
    its just the BLOW OUT after 200 yards at full throttle that I can't get rid of.
    (the outboard is at 3" past nuertral position, towards the negative side....
    tucked in!)

  5. #5
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    13,649

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    Lower the motor.----------Add a whale tail.------------Perhaps a cupped prop.

  6. #6
    Join Date
    Aug 2016
    Location
    Holland, Michigan
    Posts
    45

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    The long shaft is down as far as it go can go!
    would it help to lower the engine pod 2" all around
    by using 2 X 2 x 1/8" square tubing??

    And wouldn't a whale tail just lifetime th stern being counter
    productive. (I know they they make add on cavitation plate
    out there to add 3" all around!??

  7. #7
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    13,649

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    One way or another you need to lower the engine.----Air is getting into the prop.-----I care not how you accomplish this.------------If $$$ are not a problem an extension kit is also an option.

  8. #8
    Join Date
    Aug 2016
    Location
    Holland, Michigan
    Posts
    45

    Default Re: SunTracker pontoon with Mercury 40 hp.?

    Okie Doke! I'll start at the low end $ first and work my way up!
    ill try SE SPORT 200 hydrofoil for cavitation and ventilationand see
    what it does.

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