MTFCA Forum

Number 1 coil-cylinder not firing. Changed plug , coil. Found 1 wire loose at timer. No positive change. Coil fires if engine not running.
Appreciate help on my situation. Thanks.

Swap #1 coil with another & see if problem follows coil or stays at #1, when having coils rebuilt always have 5 done. George

The coil fires, but does the plug fire? Do you have a coilbox with original style wood in it? If so, and the coil fires, and the plug fires in the open air but not in the engine, and since the trouble is with #1, what you probably have is a carbon track in the coil box wood. It's allowing some of the current to bleed off to ground (the metal side of the coilbox, which the #1 coil is closest to). Like an iceberg, most of it is under the surface where you can't see it. To find it, you'll have to disassemble the coilbox and look at the wood panel under a bright light. Look for what appears to be a pencil stroke between the spark plug wire terminal and the end of the panel where it meets the metal. Use a knife blade or a small chisel to dig out all the charred wood you find there. You can fill the resulting channel with wood filler, or, best solution of all, replace the wood with one of John Regan's coil box plastic "wood" kits. Birdhaven now sells them. This is a permanent fix and will make your coilbox moisture/carbon issues go away for good. Experience speaking here.