so im trying to get my atv running and i took out the spark plug and realized that the center electrode and ground electrode was touching no gap at all so i pulled them apart and put it back in tried to start it almost worked but after trying to start it after a couple of minutes i took it back out and i saw the same thing: center electrode and ground electrode was touching no gap at all and i dont know what causes it and how i can fix it so any help would be appreciated

  • 2
    I'd guess that you have the wrong plug for your motor and have damaged the piston by smashing it into the plug (thus closing the gap) or you have so much carbon buildup on the piston that it doesn't clear the spark plug when at TDC.
    – user16128
    Apr 9, 2020 at 0:46
  • how do i check whats causes it tho? Apr 9, 2020 at 18:00

1 Answer 1


Get a piece of bent wire and use it to measure the plug hole depth of thread.

The sparkplug thread length should be the same as it should be flush with the combustion chamber surface.

Or you could use a vernier depth gauge for a better measurement but if you don’t have one then a piece of wire will give you an idea.

  • how i do that?? Apr 9, 2020 at 17:56
  • measuring stick or ruler.
    – Solar Mike
    Apr 9, 2020 at 18:04
  • so i stick a ruler in the spark plug hole? Apr 9, 2020 at 18:09
  • Sorry, what was the first line in my answer?
    – Solar Mike
    Apr 9, 2020 at 18:11
  • i dont know what plug hole depth of thread is Apr 9, 2020 at 18:35

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