Usually if there is a no-spark condition on one cylinder and changing the coils doesn’t change the result, look for something grounded that shouldn’t be. Wires touching that shouldn’t be, insulator(s) missing or installed in the wrong spot, etc. Check the spark plug lead on the cylinder that isn’t working, the insulation might be worn through and the bare wire grounds out on the magneto plate.
I’ve had it where some joker drove a tiny nail through the centre of the spark plug wire so that it was grounding out against the plate, but that’s another story….
PM T2
He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...
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