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1988 Force 85 / which prop ??

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  • 1988 Force 85 / which prop ??

    The prop that came on this motor/boat has the the following numbers stamped in the hub.P743-2 and 743265On the outside is stamped 13 on one side and 4360 on the other side.This prop is damaged. The dealer recommended a Michigan Wheel 071036 which is a 13.25"X17" cupped prop as a replacement. With this prop, the boat does 22mph at 2800rpm and has a WOT rpm of 4000. With the original, the WOT rpm was 5400. Any suggestions on what the original prop was, or what the proper replacement is ??

  • #2
    Re: 1988 Force 85 / which prop ??

    I have the same engine. The Force manual lists 2 props for the 1988-85hp. Both are 13.75" and either 17 or 19 pitch. If you get an uncupped prop the rpm is greater but the boat will pull hard left so get the cupped. How much does the boat weigh? Over 1200lbs use the 17", under, the 19" will work fine. My boat is the Chrysler Charger 183, a 16' hydro-vee at 1500 lbs. wet. Top speed with the 17" is 33mph by GPS. @ 5200rpm. I have a spare 12.5 X 21" prop that will move the boat at 29 mph but the revs drop to 3500 max, and the carbon build-up comes quick. Good Luck... Larry