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FS66 WEEDWACKER - NO SPARK

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Davisd2
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2021/06/13 18:08:54 (permalink)
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FS66 WEEDWACKER - NO SPARK

Tested the coil on a multimeter and tested good, no short and good resistance. Bought new plug, scraped the connection in boot, disconnected the switch wire, but still no spark. What am I missing?
Any help appreciated...Doug
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    Davisd2
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/13 18:15:38 (permalink)
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    Also sanded the surfaces of the magnet and coil and re-gapped the coil. Sparkplug wire out of the coil looks good as well. There's good compression ( by feel) ...should I check the valves next?
     
    Doug
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    Roy
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/13 20:58:00 (permalink)
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    An FS-66 is a 2 stroke, doesn't have valves. Replace the coil.
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    AVB
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/13 21:02:52 (permalink)
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    From what I can tell from the IPL I just looked ( I have better one coming) you are so far off base it isn't funny.
     
    You have a 2 cycle which doesn't valves of any kind. Also it has electronic magneto which is not testable by meters; unless, you have one highly specialized coil testers.
     
    BTW valves on any engine doesn't cause lost of spark. You have an ignition problem. Now short in the kill circuit can cause lost of spark you test for that by unpluging the coils kill terminal wire.
    post edited by AVB - 2021/06/13 22:33:16
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    AVB
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/14 07:15:40 (permalink)
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    Received a good IPL overnight.
     
    The coil is listed as NLA but you be able find a New Old Stock (NOS) or after market. Google PN 4123 400 1301.
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    Davisd2
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/14 08:19:05 (permalink)
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    Thanks all!  My error on the valves; 2 strokes are pretty new to me.
    I've read a number of sources saying that checking the resistance on a multimeter is a good test of the coil...2.5 to 5K on the 20K scale should be good.  Mine gave a reading of 4K, so thought it was okay.
     
    Some of these replacements I'm seeing only have one leg on the magneto and mine has two. Dealbreaker?
     
    Doug
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    AVB
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/14 11:26:51 (permalink)
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    Davisd2
    Thanks all!  My error on the valves; 2 strokes are pretty new to me.
    I've read a number of sources saying that checking the resistance on a multimeter is a good test of the coil...2.5 to 5K on the 20K scale should be good.  Mine gave a reading of 4K, so thought it was okay.

    That only checks the secondary windings. The problem that the primary also needs checking but the way internal electronic are connected there is no way to check it except the go/no go test; otherwords, it either works or it don't.
    Davisd2Some of these replacements I'm seeing only have one leg on the magneto and mine has two. Dealbreaker?
     
    Doug

    The new coils only need one to the kill and the other wire is probably connect the coil's frame as grounding point.
     
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    Davisd2
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    Re: FS66 WEEDWACKER - NO SPARK 2021/06/14 12:39:02 (permalink)
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    Sorry, by leg I mean the metal core that hugs the flywheel where you have to have the right gap. There are 2 on mine in the shape of a 'C' but the replacements all only have 1...guessing it saves on cost but works as well as 2?
     
    Doug
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