Posted by Denis on Wednesday, August 06, 2003 at 2:36PM :
In Reply to: coil question on M-37 that won't start..con't saga posted by George on Tuesday, August 05, 2003 at 11:30AM :
You should read +24 volts on the + connection of the coil when the ignition switch is on. The - terminal on the coil is grounded each time the points close to set up a current flow in the primary windings of the coil and hence set up a magnetic field. When the points open the current drops and the field collapses; this induces a current in the secondary winding and also because of the ratio of the number of turns between the 2 windings in the coil, a very large voltage which jumps across the spark plug gap.
To trouble shoot; if you're getting a +24 volts at the + terminal of the coil, the filter and supply voltage are OK. Next I would check your points (correctly gapped), plugs, rotor and dist cap terminals to make sure they are clean and replace the condenser inside the distributor.