Small Engines (Lawn Mowers, etc.): CD Ignition module, spark plug wire, air gap

Question
Hi Eric -
I have a Ryan 275 single cylinder 2-cycle trimmer and I suspect the igniton module is bad. The part number I found is 683390. I think I properly set the air gap. It just has the spark plug wire and a small lead to the on/off switch.  The switch's on position interrupts the continuity from the lead terminal on the switch to the block. With the wire from the module to the switch disconnected there is continuity between that terminal on the module and the block. Am I correct in assuming that this means the module is shot? Or is there something else I should do? If it is bad, do you have any idea where I might be able to get a replacement?
Any help would be appreciated.
Thanks,
Jim

Answer
If you dis-connect the small wire connected to the coil, the shut-off wire, and check for spark and do not have any spark with the small wire dis-connect the the coil is 99.9% defective.  An air gap of .012-015 of an inch should be fine.

I Googled "Ryan 683390" and found modules from several places.  You can also try your local small engine shop and see if they have any used ones.  I've known a couple of shops that would sell used coils and guarantee them for 30 days.  It's a used part but that's a bettery warranty than you get with most new coils and the shops usually only charged about $20.00 for the used ones.  Odds are a used one that works will work for a long time.

Let me know if this helps.
Eric