Hooking Up Dwell Meter

Remember dwell is nothing more than another way of measuring point gap. Setting the correct gap will give you the correct dwell unless there is serious wear in the distributor.

The tach function probably also doesn't work correctly, as its expecting to see pulsing DC as the points open & close, and actually gets a short pulse just before the points open on a mag. An inductive tach that clamps onto a spark plug wire will work just fine regardless of the source of the spark (magneto, distributor, electronics, etc.)

Keith

Unfortunately most tach/dwells do NOT work on magneto ignitions - at least neither of mine do. ...Bob M

BTW I did double 8 cyl readings. JON

Incidentally it's been too long since I "dwelled" an mechanical ignition system - I honestly cannot recall what a good 4 cyl dwell reading is anymore.

So for a slow running tractor mag, I'd simply set the breaker points to 0.013" and take whatever dwell it gives you (remember you're not running NASCAR RPM's here!). Figure as long as you have a good spark when the impulse trips you can be certain you are getting a nice fat spark while the engine runs! ...Bob