John Deere B Magneto

[hrbburn]

I got an old John Deer B that hasn't ran in about 3 years. It was running when parked, or at least thats what they always say. Anyway don't know anything about a magneto and thought that might be the place to start. It cranks over but has no spark at the spark plugs. The mag spins and the points open and close but no spark there either. Should there be any power going to the magneto? I see a wire attached but wqs told that is just to kill it. Any help to a rookie would be great appreciated. Would love to get this old girl running.

 

[ken44520978]

Very likely the points have some corrosion on them. Try to clean them up with some fine sand paper or emery cloth.

 

[Rich'sToys]

There should be no power going to the magneto.
As was mentioned, try cleaning the points first.
The wire you mentioned is indeed intended to kill it, or shut the tractor down. Trace it back to see where it goes. It's probably connected to a switch of some kind. That switch should be in the off, or open position. Turning it on completes a circuit from the mag to ground, causing it to kill the tractor. If in doubt, disconnect the wire from the mag and try starting the tractor.

 

[vvfarms]

May be Wico distributor, needs current

 

[NoDakInMN]

Assuming it is a mag and not a Wico distributor, ( they look a lot alike on the outside) does the impulse trip with an audible click as you turn it over? No impulse=no spark.

 

[jd2cyl1943]

What is the model of mag? If you have to disassemble I could offer advice because I just tore done mine. If I were you I would just replace the points. They don't cost much. Another thing is that I advise you get Roberts Carb Repair's video on rebuilding mags.
https://robertscarbrepair.com/dvd-how-to-rebuild-wico-series-magnetos/[/i]

 

[Rich'sToys]

The original poster has not checked back in. Curious as to what he found.