Reply To: Johnson 1949 HD 25 No Spark

[TiIngot]

I completely removed both sets of points and inserted a thin piece of cardboard between them.  Both sets had open circuits with cardboard inserted.  However, removing the cardboard and with the points each closed, one set still had an open circuit.  I used my points file and heavily cleaned the points and now both sets have continuity when closed and no continuity when opened with cardboard inserted. (Before I tried to clean them while installed.)

Went to O’Reilly’s and bought two new J8C plugs and a new plug spark tester.  They did not have a capacitor.  Point gaps set at .020.  Magneto gaps set at .012.  Using electric drill to spin the flywheel and still no spark in top or bottom plugs.

I am back to looking at the stop switch/circuit.  The underside of the stop switch is not easily assessable without taking the entire magneto assembly off the motor which I do not want to get into.  I have no clue what insulation is within or around the screw bolt that is in the so-called switch.    However, the nut on the top side of the stop switch is accessible.  Under this nut is two wires coming from each of the points and a waxy residue, like bees’ wax.  Both wires are unscrewed from their points to isolate them.

Both wires from the points to the switch have continuity, not broken.  With the magneto in the start position, both wires have open circuit to ground.  However, with the magneto at the stop position only the bottom short wire from the near points is grounded.  The longer wire going to the opposite points still has an open circuit.  Under the stop switch nut it looks like there may be an insulator between the two points ground wire and it looks like it may be the bees’ wax like stuff.

Anyone know what the stop switch assembly looks like or know of a reference on the internet that may describe the switch?

For testing, if I totally remove the stop switch from the ignition circuit would it change the operation or just prevent the ability to ground the points to stop the engine if running?

Still puzzled.

 

Retired titanium melt shop manager. (Think about me next time you fly in a window seat and look at the engines spinning below the wings!)