Does your mag look like this one?
It should and removing the gas tank first will make it easier to work on the mag. You can check the coils with an ohmmeter and the primary side, the two loose wires, should read really low, around one ohm. Connecting the meter to the secondary winding, the spark plug terminal and one of the wires, should give a reading around 3.5 thousand ohms. The secondaries can read a bit higher or lower and still work fine. While the ohmmeter is out, take a reading of each spark plug wire from the plugs terminal to the terminal on the coil. Again, the reading should be really low.
In this batch of coils, only half of them were any good. That is uncommon.
As stated, work on one set of points at a time so you don’t get the parts mixed up. All of the brass parts should be degreased and polished to remove any tarnish. They have to have continuity between them and if they aren’t clean, chances are they wont work. The points can be cleaned and polished with wet n dry paper. 400 – 600 grit will remove any pitting or oxidation and finishing with finer grades up to 1500 or 2000 will put a mirror finish on them. The original condensers were rated at 0.16 – 0.24 uF so they should be tested or replaced if in doubt.
When installing the points, make sure the rounded end of the plunger rod goes towards the points with the square end towards the crankshaft.
If you remove the coils, they will have to be gapped to the rotor magnet using these instructions.
