Spark Plug Wire

Discussion in 'Tech Area' started by Dennis McDonaugh, Mar 23, 2020.

  1. Dennis McDonaugh

    Mar 19, 2020
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    Can you replace the wire or is it molded into the coil? My wire insulation is in pretty bad shape.
  3. hrc200x

    hrc200x Active Member

    Sep 27, 2005
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    Molded, most are cut too short from previous owners, ive had luck stripping the wire and splicing in some new wire thats more flexible to make it the correct length. Solder the wire, put in old wire insulation over the splice, then get some good heat shrink tubing over everything, the kind that has the glue squirt out. If yours is bad up close to the coil a new one might be needed.
    racerx likes this.
  4. racerx

    racerx Administrator
    Staff Member Administrator

    Jul 10, 2005
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    This has been my preferred repair method for many years, now. It's permanent, solid and requires less than $2 worth of supplies...if you have them on hand. The main obstacle is getting a short length of plug wire to splice onto the clipped lead. Multistrand copper plug wire isn't exactly common anymore, so there's the shipping cost to deal with.

    As long as you don't loop the ends, before twisting & soldering, the splic should be close enough to the original wire diameter to cover with a split section of inner insulation...salvaged from the end you just clipped. That makes a nice strain relief and reduces the amount of tape needed to match the OD of the splice with the rest of the lead. Self-fusing silicone tape is an ideal material...and can be used right from the bare conductor, it just takes more of it. At the end of the mummy-wrapping, you want to extend the tape an inch or so in both directions, as a second strain-relief and for thorough water-proofing. Then, a 2-3" length of shrink tubing gets applied, making a permanent repair. Many of the 1970s models came from the factory wearing an outer layer of polymer tubing over the plug lead. That makes life easy for those seeking an invisible repair.

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