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1987 Force 125 hp

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  • 1987 Force 125 hp

    1987 force 125 hp

    I just joined but I love this forum some of you guys are top notch.

    at full throttle motor sometime feels like it throttles down for a brief amount of time.

    I have video:

    Listen while the boat misses, at seconds: 28 43 49-51 53 58 59 1:01 1:06 1:15-1:17 1:24-1:25 1:39 1:43-1:49 1:53

    I have spark

    just changed the fuel feed hose

    I have equal compression

    Update: Today I took it out and it was the worse @ WOT went to 15 mph then back down to 5 mph was as much as I could get something is very wrong.

    I would love your suggestions

  • #2
    Re: 1987 Force 125 hp

    it seems to me that you are losing gas out of some of the carbs,try cleaning out the fuel bowls on them and make sure the needle seats and fuel passages in them are clear,125hp you have 4 carbs any one acts up it shows up when you go wot.


    • #3
      Re: 1987 Force 125 hp

      You might want to check/re-build the fuel pump, especially the diaphragm. Cheap,easy, and needed maintenance. I'm not 100% sure from what I saw/heard that you are not intermittently losing spark at higher RPM's. I'm not sure what type of ignition you have on your rig, but I'd also check the coil(s) and/or cd box(s). I'm sure someone more knowledgeable will chime in. Good luck...

      Nebraska Football, there is NO substitute! If I have to explain you'd never understand. GO BIG RED!!!


      • #4
        Re: 1987 Force 125 hp

        I don't know how to check for spark at higher RPM or how to check my CD boxes at load. But I did check for regular spark and I have that.


        • #5
          Re: 1987 Force 125 hp

          I think you and i have the same motor. Same paint, stickers, etc. I figured out I was losing spark on one cylinder at high speeds because I had eliminated everything else.....Then I had someone run the motor at wot while i took out the plugs and grounded them, one at a time....kind of a pain to do. I am no mechanic, but you might check your fuel tank.....do you have a screen in the bottom of your pick up tube? Mine was partially plugged one time...I couldn't get the pick up tube unscrewed from the tank, but I blew compressed air through the line and that cleared it. You could have the same spark problem I have, also....I'll let you know if I am able to fix mine.


          • #6
            Re: 1987 Force 125 hp

            thanks for the heads up I'll go and look, I've checked the fuel before, but the winter was a harsh one I might just get a spare outboard tank and hook it up. to check if it is a fuel problem.

            Also I'll replace the diaphram this week.

            Now the WOT test that you did tell me more,
            did you use muffs in neutral?
            or at the lake in neutral?
            When I put it in neutral I can't get all the way to WOT

            someone in these threads mentioned the voltage regulator, I'll check that this week too.


            • #7
              Re: 1987 Force 125 hp

              I haven't posted here in a long time, but think I can save ya a headache chasing yer tail. Its ZIP to do with gas. Its the well known dreaded "Force ignition" Same thing happened to my 88.

              You need a Stator, possible one of the 2 power packs, and have the coils checked. But trust me, its the Stator causing this. Replace with the Merc upgraded one. Find a good Force/Merc wrench, and start handing over money. Trust me, as it has nothing to do with gas.


              • #8
                Re: 1987 Force 125 hp

                What's the source and part number for the upgraded stator?

                I'm inclined to agree with you as I'm having similar issues with my 84 125HP
                1984 Bayliner Capri 1900 BR - Chrysler 125

                "If it ain't broke, break it and fix it - only way to learn!"


                • #9
                  Re: 1987 Force 125 hp


                  I found this site:

                  They have parts and testing procedure.

                  Well I'm going to replace the diapram today, maybe the rest of the fuel lines, then I'll see if I can figure out how to test it.


                  • #10
                    Sign up today
                    Re: 1987 Force 125 hp

                    Did you ever get your engine running correctly? Turned out I was barking up the wrong tree on my 1987 125 Force....the float level on one of the carbs was off.........that was the real problem.