Home Forum Ask A Member Mercury KD4

Viewing 10 posts - 1 through 10 (of 140 total)
  • Author
    Posts
  • #226332
    Boonie
    Participant

      Canada Member

      Hey everyone. This is my first time posting on this site. I am curently restoring a Mercury KD4 and i need some help with ignition coils. How to test if they are any good and if not, help finding replacements?

      #226343
      green-thumbs
      Participant

        US Member - 2 Years

        Mercury KD4 (early) had Eisemann 72H magneto ignition system
        Bendix Scintilla magneto ignition systems were used on later KD4
        The magnetos are entirely different with no parts in common.
        SO,,,first order of business is to find out which magneto is on your KD4.
        and report back.
        Magnetos are not my strong point so hopefully some one will share
        a little know how with us.
        Louis

        #226352
        billw
        Participant

          US Member

          It has been my personal experience that the Eisemann coils always work and the Bendix ones never do, at least on Mercurys. (Why they seem to be okay on Champions I have had, I have no idea.) The Bendix coils are held in place with snap clips, while the Eiesmanns are held in place with screws. That is a quick visual ID of what you might have.

          Long live American manufacturing!

          #226355
          Boonie
          Participant

            Canada Member

            They are bendix coils

            #226360
            fifty20ne
            Participant

              US Member

              These Diagrams may help.

              Good Luck,

              Bob

              Chart1

              Chart3

              Chart4

              chart5

              #226366
              fifty20ne
              Participant

                US Member

                Chart6

                Chart7

                Chart8

                194620Mercury20ad20b

                Mercury-Outboards-Through-the-Years0015

                • This reply was modified 3 years, 11 months ago by fifty20ne.
                • This reply was modified 3 years, 11 months ago by fifty20ne.
                #226373
                fifty20ne
                Participant

                  US Member

                  MERCURY PARTS/PRICE LIST LINK.

                  https://drive.google.com/file/d/0B6wRLMxPeVaiOWIxNDRkZWItOWRjMC00YTJhLTg3YWQtNDU3OWY2ZjRjZjlh/view?hl=en

                  http://pub9.bravenet.com/photocenter/album.php?usernum=737212788&album=49338#bn-photocenter-1-1-737212788/49067/1/

                  KD4

                  KD4WLL

                  KD4WLL2

                  29e67456efbbe06c0d1ef69174758fe5

                  • This reply was modified 3 years, 11 months ago by fifty20ne.
                  • This reply was modified 3 years, 11 months ago by fifty20ne.
                  • This reply was modified 3 years, 11 months ago by fifty20ne.
                  • This reply was modified 3 years, 11 months ago by fifty20ne.
                  #226381
                  Boonie
                  Participant

                    Canada Member

                    Thanks Bob. Could be a problem finding replacements!

                    #226390
                    billw
                    Participant

                      US Member

                      They are bendix coils

                      Well, all is not completely lost yet. Are they all cracked and disintegrating? Best not to try to use those. If, by some miracle, they are NOT all cracked, they MIGHT still work. Next steps would be to remove and CAREFULLY disassemble the points, and clean the contacts to like new condition. I say, “CAREFULLY,” because there are a lot of tiny little parts. Make particular note of where the tiny insulating bushings and washers go. Do one set at a time and make a drawing and/or take pictures of them, as you take them apart. Once the points are clean, ( I use 320 Emery cloth, changed frequently as the points are a very hard material.) reassemble them as you found them. Then, set the point gap at the high point of the cam. Somebody correct me if I am wrong, but I believe the setting is .020″. Now, with nothing connected to the points yet, connect an ohm meter to a point terminal and to the base plate. Turn the engine slowly by hand. On your meter, you should see the reading change between OL and LESS than 0.5 ohm. Preferably, ZERO ohms. If this is not the case, go back to something you did wrong with cleaning, reassembling and installing the points.

                      The condensers will definitely be bad, unless somebody has changed them recently. I like to use whatever automotive condenser will fit in its place. I used to have a NAPA/Echlin number in my head, but not at the moment. When you have new condensers, hook them and the coils, to the points, install the flywheel, pull the engine over rapidly and check for spark. A Bendix mag is absolutely STELLAR if it will even jump a 1/4″ gap. 3/16″ is more realistic. An old spark plug can be made into a checker, by opening the gap on the plug way up. Godspeed.

                      Long live American manufacturing!

                      1 user thanked author for this post.
                      #226394
                      Boonie
                      Participant

                        Canada Member

                        I found some coils on http://www.oldmercs.com
                        Product code 399-125.
                        Can anybody have a look and see if they think they will work on a kD4 Merc with a Bendix Scintilla mag.

                      Viewing 10 posts - 1 through 10 (of 140 total)
                      • You must be logged in to reply to this topic.