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Weak Spark

Ok, you have a spark at the spark plug, but it’s not a sharp, white spark.  I had a 102 one time that had what looked like a fuzzy, blue spark.  That turned out to be a condenser problem.  The condenser is in the circuit to prevent the points arcing across as they open.  (The condenser “absorbs” some of the current as the points open reducing the potential for arcing.)    If the condenser is not working, the points will arc preventing the magnetic field to collapse fast enough to create a high voltage in the secondary side of the coil.  The lower voltage will result in a weak, fuzzy spark instead of the sharp, crisp spark that’s needed.  A bad condenser also will cause premature failure of the points as a result of pitting.  Use your voltmeter to check the condenser.

Still under construction!!


A bad coil can also cause a spark failure or a weak spark.


{coil schematic}

Last Modified On: 2014-03-09 17:54:26