1970-1979 Ski-Doo Snowmobiles Service Manual, Page 120Get this manual
ELECTRICAL SYSTEM
bConnect ohmmeter between ground and red wire in junction block (not on electronic box)Ohmmeter should indicate 325-365 ohmscIf resistance is not as specified, remove armature plate as outlined in Chapter Four and have an authorized dealer replace ignition generator coildIf resistance is within tolerance, replace electronic boxeReconnect all junction blocks
MAGNETO IGNITION