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Re: FM Magneto no spark

R

ryanwheelock

Member
The magneto on the Wisconsin VF4 isnt working, at first the points werent opening because the breaker arm was worn and not opening the points when the cam turned. Adjusted the points so they open and adjusted the gap, still no spark. Checked the Impulse coupling and its snapping when turned over. Dont know how to test the Condenser or the coil windings, dont think I have the right equipment. Am I better off tring to repair this one or should I pick-up a used Magneto??
Any input would really help.
Thanks
Ryan in Northern Michigan.
 
Did you thoroughly clean the points as I suggested in a previous post?

MANY little DVM's have a capacitor test function.

Can you beg borrow or steal one?
 
I will add to Bob's good advice that the worn rubbing block can affect the timing of the opening. as a result it will fail to have enough energy at the point opening moment to fire. A condenser can be checked with a 6 or 12v battery and a volt meter. Hook the battery to the condenser (either polarity is fine), then after about a minute, remove it. Use the volt meter to check the condenser in the same polarity it was charged. The meter should start at battery volts, and then fall to zero as it discharges into the meter. Time is not an element here. If it will hold a charge for a second, it is neither open (bad) or shorted (bad). this test does not define the total worth of the condenser as it operates in the hundreds of volt range. But it weeds out the majority. The coil windings can be checked for continuity and improper short to ground, but you will need a diagram of the connections to do so. the points will need to be held open to test the coil components. JimN
 
One thing is rust or corrosion where the metal slats around the armature is. Take it apart and clean it good then try. also check for residual magnetism it may have lost what it had and will have to redone by someone who has the tools.
Walt
 
Or, perhaps improper grounding of the battery will let the smoke out. Got over that one yet, Walt?
 
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