I don't get many of the smaller engines to work on as consumers here opting for handheld trimmers and ZTR, current fad.
IF it is the later type it more likely poor solder joints on the SMD circuit board contained with the coil. Or at least that what was wrong with the one I took apart. I also was curious what what in there too. Most SMD components except one D13003 transistor. No diode protecting the coil if a positive voltage is connected to the kill tab which would destroy the electronics.
Usually the coil problems I have on walk behind mowers are where the dog or mice have chewed the hi tension lead (plug wire) so I just replace the lead.
