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max rpm 50 hp mercury??

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  • max rpm 50 hp mercury??

    i have a 1987 50 hp mercury outboard...it runs good but i dont know what best running rpm's is and dont know how to find out...it doesnt say on the serial plate what the max rpms should be...any help? thanks guys.

  • #2
    Re: max rpm 50 hp mercury??

    WOT should be 5000-5500 RPMs
    "A manual is a cheap investment"
    Fair Winds and Following Seas
    Bill
    PTC USN ret

    Comment


    • #3
      Re: max rpm 50 hp mercury??

      how would i be able to check it? i dont have any guages on my boat...

      Comment


      • #4
        Re: max rpm 50 hp mercury??

        You will need a tachometer.
        "A manual is a cheap investment"
        Fair Winds and Following Seas
        Bill
        PTC USN ret

        Comment


        • #5
          Re: max rpm 50 hp mercury??

          Tyler, now that you know your WOT RPM range, without a tachometer, knowing if you're exceeding the maximum RPM is impossible. However, if your boat is between 14 and 16 feet in length, the propeller is the factory recommended size and style, and your WOT timing is set to factory specs you'll probably never exceed max RPM by any damaging amount.

          If you've altered the timing or changed the prop then you should install a tachometer to monitor max RPMS and also see if the changes you made were effective or not.

          Here's the funny part, the original warranty states to never exceed max RPM's. Dealers, boat manufacturers, customers, ect. installed thousands of these motors on boats without any means of knowing (tach) what the max RPM's were. It was Merc's golden parachute for voiding warranties.

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          • #6
            Re: max rpm 50 hp mercury??

            Where would i hook up the tachometer then? and can i use just any tachometer like say from advance auto or something?

            Comment


            • #7
              Re: max rpm 50 hp mercury??

              Originally posted by Jlawsen View Post
              .

              Here's the funny part, the original warranty states to never exceed max RPM's. Dealers, boat manufacturers, customers, ect. installed thousands of these motors on boats without any means of knowing (tach) what the max RPM's were. It was Merc's golden parachute for voiding warranties.
              That's a crock. The dealers had charts and other guides to aid the selection of a prop. Also, after they had rigged and sold a few dozen boats the dealers had a pretty good idea what was close.

              Comment


              • #8
                Re: max rpm 50 hp mercury??

                another issue im having is when its out of water and on the water muffs in couldnt run any better...in the water i have to idle it way up then thow it into gear quickly or it will shut off....idleing to low maybe??

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                • #9
                  Re: max rpm 50 hp mercury??

                  You have to use a tach made for an outboard. Automotive tachs will not work. Your carbs need adjusting. Follow the link & sync procedure given in your manual.
                  "A manual is a cheap investment"
                  Fair Winds and Following Seas
                  Bill
                  PTC USN ret

                  Comment


                  • #10
                    Sign up today
                    Re: max rpm 50 hp mercury??

                    ah ok....ill have to fool with it some then and see how it does... thanks guys!

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