Posted by ScottyHOMEy on November 01, 2009 at 12:26:06 from (70.105.226.144):
In Reply to: Re: C magneto posted by jim from az on November 01, 2009 at 11:50:44:
Nope, it can't make the spark if any one of the points, condenser or coil aren't working.
The magneto concept is only slightly different from that of the battery ignition. The only difference is the source of the armature rotating inside a field to generate the juice. It's internal to the mag, which has a permanent magnet in its shaft. On a battery ignition with the external coil, the permanent magnet of the mag is replaced by an electrically induced magnetic field, an electromagnet, instead of a permanent magnet within a coil.
All of this is overly simplistic, but is, I think, close enough to address your question.
Basic misconception is that the spark happens when the points close to complete a circuit.
The way it actually happens is that while the points are closed, completing a circuit to ground giving the generated electricity a path to flow, the coil is building a charge in the field between the magnet and the coil. The spark occurs when the points OPEN, causing that field tocollapse, releasing its energy to the coil wire to be distributed through the rotor and cap to your plug wires. The condenser is there as a kind of electrical shock absorber, so that the energy doesn't flow back through your points, which would keep the charge from building up or, once it's released, flowing back through the points instead of the coil wire, which would smoke the points in VERY short order.
So . . . 1) dirty/corroded points will deny the whole works a path to ground to build a charge in the first place. There will be no field there to collapse when the points open. 2) a faulty condenser will keep the charge from building by not dampening the flow back to the points, or will fry the points. 3) a faulty coil will not respond to the stimulus of the magnet spinning inside it and will not be generating a charge in the first place, rendering the points and the condenser irrelevant. By that same token, going back to my earlier post, a too-weak magnet wont be enough to stimulate the field within the coil, either, but the magnet might be the last thing to look at.
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