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How To Replace A Spark Plug Cap?

Discussion in 'XJ Technical Chat' started by moshumi13, Feb 17, 2012.

  1. moshumi13

    moshumi13 Member

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    Hey,
    I need to replace one of the spark plug caps and understand vaguely, but a more detailed description would help a lot. Can't find a decent how to anywhere.

    Thanks
     
  2. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    Grasp the wire in one hand. Grasp the plug cap in the other. Unscrew the cap from the wire.

    Honestly, that's all there is to it. There's a threaded spike inside the tip of the cap that screws into the core of the wire.

    However: There's also a resistor core inside the cap (inside the spark plug side) that also screws in. These can work loose and make you think you have a bad cap or other unrelated problem.

    You can simply slip the big rubber boot (over the plug end) off for easier access. The resistor core has screwdriver slots on either side of the hole for the plug terminal.

    Lop about 1/4" or so off the wire before screwing a cap back on, so it will get a fresh "bite."
     
  3. moshumi13

    moshumi13 Member

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    The core of the cap is BLOWN. There is nothing inside. The jet looking thing that hooks to the plug was on the plug and is on my bench. This was blown a long time ago. I have to take the whole cap off and install a new one. I guess I have to destroy this cap to get the wire. I'm not trying to re-wire the coils. Once I get the old cap off how do I set up the new plug. I have read the basics, but it just says to bend the wire up to the insulation and then crimp. Then pull the boot on. It'll get done when the time comes, I guess. Trying to save as much wire as possible so as not to have to replace the coil pack. That would suck! Just got the electrics run right.
     
  4. jamings67

    jamings67 Member

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    jUST CUT THE WIRE AT THE CAP AND INSTALL A NEW CAP NGK CAPS ARE GOOD AND HAVE A NIPPLE THAT SCREWS INTO THE CENTER OF THE CUT WIRE REPLACE ALL FOUR AND GOOD TO GO.

    SORRY FOR CAPS
     
  5. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    You missed my point. The caps unscrew. You need to use resistor caps similar to what you took off though; the 550s use 10K Ohm caps. The new cap should just screw onto/into the wire like the original.
     
  6. moshumi13

    moshumi13 Member

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    Ok, thanks.
     

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