Before bothering with the rest of the system, first check the spark plug gap. Set for .030in, or actually .028-.032in to be exact.

The reason I say this is because it's often wet wires and high resistance (big gap) at the plugs that cause the problem. Plust the fact that the wires are arcing somewhere along the line, very easy to see if it is totally dark, but almost impossible in the daylight, or with a flashlight.

Replace the plugs if they're out of spec. You can regap plugs if you're in a bind, but at a couple of bucks apiece, there's no compelling reason to do so. I never personally reuse plugs, since they seem to have a reasonable life without adjusting the gap. Just dump a set of new plugs in at correct gap, use antiseize blah blah blah, and go from there.

If the plugs are NEW and the correct gap, suspect other problems elsewhere. The crank sensor can go weird in wet conditions. Another cheap fix, and more of a routine maintenance piece in my opinion. They can go bad either all at once--100%--or they can have off and on times. Neither is good, and for $35 it is well worth the money to just put a new one in and forget about that problem for the next five years or maybe ten. Don't bust the bracket it sits in!!! Easy to do, believe me.

The coil wire might be arcing also, and that REALLY makes a mess of starting. Again, path of least resistance, etc.

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Chris Herbst, in Wisconsin.