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Ignition Question

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Ignition Question


Post by King » Mon Jan 21, 2008 7:16 pm

Hi All
My 51FL is not starting. It is getting gas and the spark looks right but when I kick it over all I get is backfiring through the carb like a dragon. I think that the timing is off and too far advanced. Is that right?

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Post by Skip » Mon Jan 21, 2008 7:36 pm

is your battery up and good?....what carb.....sounds flooded to me....have you done anything to it since last start up?....may not be timing at all....but it could be.....Skip

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Post by FlatHeadSix » Mon Jan 21, 2008 8:40 pm


Too much advance usually results in kickback if everything else is ok. Too much retard will cause backfire through the carb.

How is your valve adjustment?


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Post by Cotten » Tue Jan 22, 2008 1:01 am

Evil manifold leak strikes again.

Time to bubbletest:

Good luck,


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Post by PanPal » Tue Jan 22, 2008 4:47 pm

Perhaps the manifold leak or..............
if you have a spare coil, wire it in and hang it beside yours and give it a try. This sounds like the same symptoms I had last year when I found one of the spark plug wire ends going into the coil had started to turn green inside.

Depending on you circuit breaker style. Make sure you are getting a good ground through it to the motor.

My spark looked good as well.

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