Wobble WILL change dwell. Consider a shaft bent slight towards one lobe
and away from the other. The lobe the shaft is bent towards will open the
points sooner (which is what changes the timing), open them wider, and
keep them open longer, thus you'll have less dwell (the number of degrees
that the points are closed--usually expressed as half the degrees for some
strange reason). You won't necessarily see it on some dwell meters because
they show the average, but with a good dwell meter and a four cylinder
motor at low RPM you'll see twitchiness in the needle--which is a good
indication of a worn or bent shaft. It's real easy to see on a 'scope.
|