Farmall cub won't stay running after you disconnect battery

[Farmer Steve]

I thought the engine would stay running if you disconnected the battery. Mine dies. Is that what it is suppose to do???? If not what is wrong?
Thanks in advance Steve

[Donny M]

Welcome Farmer Steve,

The tractor will only stay running with the battery disconnected if you have a magneto ignition. Except if the mag coil is bypassed. If you have a battery ignition (distributor) the tractor will die when you disconnect the battery.
Which type do you have?
If magneto, check to see if there's an external coil mounted. If so the mag coil has been bypassed and the coil is connected to the battery.

Good Luck

[Farmer Steve]

It has a distributor and coil.

[Donny M]

That should answer your question.

[John *.?-!.* cub owner]

Most engines equipped with alternators will keep running, but not generators. Also disconnecting your battery while running is risking damage to the generater.

[Donny M]

Thanks, John I forgot about that.

[Merlin]

If the generator is putting out, it will run a short time after unhooking the battery. Thats the way we always check the generator to see if it is putting out. If it died, the first thing I check is the brushes. If it stayed running and was still discharging, I replace the regulator.