Author Topic: Yellow spark  (Read 827 times)

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Offline jacquesleclochard

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Yellow spark
« on: May 18, 2011, 07:44:05 AM »
Hello! After a traffic accident, my engine turns over, tries to fire up, but isn't igniting. I took out the fourth plug, and saw a yellow spark. Rather strong and very consistent. But this is supposed to be blue, right? What could it be?

Offline tlbranth

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Re: Yellow spark
« Reply #1 on: May 18, 2011, 07:49:53 AM »
pull that plug, pour a SMALL amount of fuel in the cylinder - preferably with 2-stroke oil in it, replace plug and try starting. If it fires, you have a fuel problem. That's a start.
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Offline jacquesleclochard

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Re: Yellow spark
« Reply #2 on: May 18, 2011, 11:51:36 PM »
I'll do that, but the plug, sparks a yellow spark. That would indicate a gremlin in my plugs, coils or ignition, right? Anyone has had this problem?

Offline trueblue

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Re: Yellow spark
« Reply #3 on: May 19, 2011, 12:18:54 AM »
if the spark can jump a gap of about 3/8 inch in the open air it should still run the engine, fuel doesn't care what colour the spark is as long as it is there. 
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Offline TwoTired

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Re: Yellow spark
« Reply #4 on: May 19, 2011, 02:21:14 AM »
The spark is a plasma channel made in the atmosphere (if out in the open).  Similar to neon signs, they can take on a different color by using different impurities in the gas.

Anyway, color has more to do with the atmosphere than with the voltage.

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Offline Toxic

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Re: Yellow spark
« Reply #5 on: May 19, 2011, 03:44:35 AM »
Geez, I learn something everytime TT posts.  Thanks

The spark is a plasma channel made in the atmosphere (if out in the open).  Similar to neon signs, they can take on a different color by using different impurities in the gas.

Anyway, color has more to do with the atmosphere than with the voltage.

Cheers,