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Fix my lawn mower please!

  1. Jun 6, 2007 #1
    Ok -- My lawn mower has a lame kill switch that creates a ground to the chassis when the handle is released. I am on my third switch and I am sick of tearing it apart to replace it.

    I want to replace it with a toggle switch that will ground the spark to ground when I want to shut it off. I know the spark is high voltage. I am wondering what rating I should get the toggle switch so I don't fry it.

    I think the ground wire is about 16 guage, so I am assuming a 600V 10A switch should be plenty. Am I over or under estimating it?

  2. jcsd
  3. Jun 6, 2007 #2
    a toggle switch is just asking for bad things to happen. how does the current switch keep breaking?
    Last edited: Jun 6, 2007
  4. Jun 6, 2007 #3
    I know the handle release is for safety -- but this model has this weird switch that is basically 1/2 a paper clip in a plastic container that is squeezed together to form a connection from the magnet producing the sparks to the chassis rather than the spark plug. the problem is the way the switch is actuated either gets jammed, the hook comes loose, or the switch gets worn.

    I understand the safety concern, but I just want an easier way to shut this off over having the switch wear out and then having to pull the spark plug wire off. In the end, this will be safer than not knowing if the original switch won't work.
  5. Jun 6, 2007 #4


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    Hi wxrocks,
    The toggle switch isn't high voltage, it's no more than 12 VDC, and amps are very low too, less than 10 amps, probably 5 or less. Just about any switch should work.

    You could get a spring loaded switch that makes contact when you release the button if you want to retain the safety feature.
  6. Jun 6, 2007 #5
    You can also move the small throttle linkage on the side of the carburator, that will stop the engine by starving the engine of gas. Its not as safe as a kill switch, but it is a lot easier than installing a new switch. If you move the linkage one way and the engine revs up, move it the other way and the mover will die. The linkage is located just below the air filter, and may become hot after you have been mowing for sometime.
  7. Jun 6, 2007 #6


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    One of the older (60's) mowers that I remember had a strip of springy metal like from a soup can that wrapped around the head of the spark plug just on the near side of the connector boot, in contact with the electrode, and stuck up in the air. When the owner wanted to stop the thing, he just pushed the strip against the engine housing with his foot. I don't know if it was jury-rigged or if the thing was bought that way, but it worked. Maybe you could try that before mucking about with switches. It won't cost you anything.
  8. Jun 6, 2007 #7


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    Why not replace the low voltage switch that is breaking with a good toggle switch?

    Most kill switches, ground the points not the spark plug.
  9. Jul 30, 2008 #8
    when ever i put my lwn mower in forwerd gear it goes about a foot then stops wjhat could that be
  10. Jul 30, 2008 #9


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    Does the motor keep running?
    Or does that stop also?
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