Coil Wire Shoting to shielding Lid? - NCRS Discussion Boards

Coil Wire Shoting to shielding Lid?

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • steve wallach

    Coil Wire Shoting to shielding Lid?

    I have gone through two coil wires and each time I tighten the shield lid down, the coil wire cracks at the top causing a short...

    Is there an adjustment to the shield box or the coil bracket that would solve this problem?

    (this is on a 67 427/390)

    Thank You for any Help!

    Steve
  • Jack H.
    Extremely Frequent Poster
    • April 1, 1990
    • 9906

    #2
    Re: Coil Wire Shoting to shielding Lid?

    It's not clear from your post whether you're talking about the coil primary or secondary wires... The primary wires run from the ballast resistor on the fire wall to the coil then back out/over to the distributor. The secondary wire is a LARGE diameter short run from the center of distributor cap to the coil's upper tower.

    Primary wires shorting are typically caused by the original wires having been repaired, shortened, and rubbing/chafing against the sharp edges of the LOWER side of the ignition shielding box. Secondary wires shorting out are generally caused by another factor.

    The inside bottom of the upper ignition shield cover was insulated with a clear plastic material that was simply glued in place. This mylar served two roles: (1) it provided dielectric insulation to thwart stray spark discharge, and (2) served as a smooth bearing surface to keep the secondary wire from the distributor to the coil from rubbing/chaffing against the ignition shield's upper lid.

    If your lid lacks its original mylar insulator, they're available from most of the catalog houses, die-cut, and ready to glue in place for only a few $$$....

    Comment

    • Jack H.
      Extremely Frequent Poster
      • April 1, 1990
      • 9906

      #3
      Re: Coil Wire Shoting to shielding Lid?

      It's not clear from your post whether you're talking about the coil primary or secondary wires... The primary wires run from the ballast resistor on the fire wall to the coil then back out/over to the distributor. The secondary wire is a LARGE diameter short run from the center of distributor cap to the coil's upper tower.

      Primary wires shorting are typically caused by the original wires having been repaired, shortened, and rubbing/chafing against the sharp edges of the LOWER side of the ignition shielding box. Secondary wires shorting out are generally caused by another factor.

      The inside bottom of the upper ignition shield cover was insulated with a clear plastic material that was simply glued in place. This mylar served two roles: (1) it provided dielectric insulation to thwart stray spark discharge, and (2) served as a smooth bearing surface to keep the secondary wire from the distributor to the coil from rubbing/chaffing against the ignition shield's upper lid.

      If your lid lacks its original mylar insulator, they're available from most of the catalog houses, die-cut, and ready to glue in place for only a few $$$....

      Comment

      • Tom S.
        Extremely Frequent Poster
        • March 1, 2004
        • 1087

        #4
        Re: Coil Wire Shoting to shielding Lid?

        Use slugs instead of shot!

        Comment

        • Tom S.
          Extremely Frequent Poster
          • March 1, 2004
          • 1087

          #5
          Re: Coil Wire Shoting to shielding Lid?

          Use slugs instead of shot!

          Comment

          • steve wallach

            #6
            Re: Coil Wire Shoting to shielding Lid?

            Fast Fingers, slow brain...

            The Coil Wire from the Dist. Cap is "SHORTING" to the Shield Cover. When the Shield Cover is tightened down, it smashes the wire at the top of the Coil that goes to the Dist. Cap causing a crack in the rubber, then a "short" occurs.

            The hump in the lid seems to be too far forward to clear the wire at the very top of the coil.

            Can the box be adjusted to move the hump in the lid back somehow ?

            Thanks Again,

            Steve

            Comment

            • steve wallach

              #7
              Re: Coil Wire Shoting to shielding Lid?

              Fast Fingers, slow brain...

              The Coil Wire from the Dist. Cap is "SHORTING" to the Shield Cover. When the Shield Cover is tightened down, it smashes the wire at the top of the Coil that goes to the Dist. Cap causing a crack in the rubber, then a "short" occurs.

              The hump in the lid seems to be too far forward to clear the wire at the very top of the coil.

              Can the box be adjusted to move the hump in the lid back somehow ?

              Thanks Again,

              Steve

              Comment

              • Kent K.
                Extremely Frequent Poster
                • December 1, 1982
                • 1139

                #8
                Re: Coil Wire Shoting to shielding Lid?

                Jack ---- My original '67 distributor shield plastic insulator is secured in place with plastic rivets, not glue.
                Regards, Kent Keech
                Future Lung Cancer Survivor
                Kent
                1967 327/300 Convert. w/ Air - Duntoved in 1994
                1969 427/435 Coupe - 1 previous owner
                2006 Coupe - Driver & Fun Car !!!
                NCM Founder - Member #718

                Comment

                • Kent K.
                  Extremely Frequent Poster
                  • December 1, 1982
                  • 1139

                  #9
                  Re: Coil Wire Shoting to shielding Lid?

                  Jack ---- My original '67 distributor shield plastic insulator is secured in place with plastic rivets, not glue.
                  Regards, Kent Keech
                  Future Lung Cancer Survivor
                  Kent
                  1967 327/300 Convert. w/ Air - Duntoved in 1994
                  1969 427/435 Coupe - 1 previous owner
                  2006 Coupe - Driver & Fun Car !!!
                  NCM Founder - Member #718

                  Comment

                  • Dave Suesz

                    #10
                    Re: Coil Wire Shorting to shielding Lid?

                    Yeah, I'll echo that insulation, even though I have a 55, the inside of the top cover is covered with basically a cardboard insulator to avoid the cables having physical contact with the steel lid.

                    Comment

                    • Dave Suesz

                      #11
                      Re: Coil Wire Shorting to shielding Lid?

                      Yeah, I'll echo that insulation, even though I have a 55, the inside of the top cover is covered with basically a cardboard insulator to avoid the cables having physical contact with the steel lid.

                      Comment

                      • Jack H.
                        Extremely Frequent Poster
                        • April 1, 1990
                        • 9906

                        #12
                        Re: Coil Wire Shoting to shielding Lid?

                        Yeah, different methods were used at different times (aluminum rivets, plastic rivets, plus glue). Specifics of construction depend on which version/when (typically discussed in the applicable JG book's text). But, the big picture is whether or not the actual mylar insulator is present on the bottom side of the distributor shield cover. That's the 'gut' issue I was trying to surface....

                        Comment

                        • Jack H.
                          Extremely Frequent Poster
                          • April 1, 1990
                          • 9906

                          #13
                          Re: Coil Wire Shoting to shielding Lid?

                          Yeah, different methods were used at different times (aluminum rivets, plastic rivets, plus glue). Specifics of construction depend on which version/when (typically discussed in the applicable JG book's text). But, the big picture is whether or not the actual mylar insulator is present on the bottom side of the distributor shield cover. That's the 'gut' issue I was trying to surface....

                          Comment

                          • Mike G.
                            Expired
                            • April 30, 1997
                            • 14

                            #14
                            Re: Coil Wire Shorting to shielding Lid?

                            I had the same problem with the coil wire, I just pushed the shielding backwards a little to get the groove over the coil wire. Mike

                            Comment

                            • Mike G.
                              Expired
                              • April 30, 1997
                              • 14

                              #15
                              Re: Coil Wire Shorting to shielding Lid?

                              I had the same problem with the coil wire, I just pushed the shielding backwards a little to get the groove over the coil wire. Mike

                              Comment

                              Working...
                              Searching...Please wait.
                              An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

                              Please push the back button and reload the previous window.'
                              An unexpected error was returned: 'Your submission could not be processed because the token has expired.

                              Please push the back button and reload the previous window.'
                              An internal error has occurred and the module cannot be displayed.
                              There are no results that meet this criteria.
                              Search Result for "|||"