G'day Norm,
I've had too many mowers that run good them next time you get the mower out it wont run but has spark with the
plug out, then I replace the coil and it fixes the problem.
I have a lot of spares so I don't mind changing a coil even if it's just to rule out a coil problem,.
As we know. When the spark plug is removed, the ignition coil can sometimes generate a visible or audible spark across the spark plug gap without the load of the plug. This is known as a "no-load" spark test. Since there's no spark plug in the cylinder, the spark has less resistance and can appear more easily.
When the spark plug is in place, the ignition coil has to produce a spark strong enough to jump the gap between the center and side electrodes of the plug under compression. If the spark isn't strong enough or the coil is weak, the spark might be insufficient to jump the plug gap when under compression.
Back in the early nineties I had a new Stihl chainsaw (a few months old),it had spark with the plug out but wouldn't fire with plug in ,put a new coil in and it was running as new again.
Your Honda may not be a coil problem but if it's got compression and fuel I like to rule out a coil problem.
Cheers
Max.
