Reply To: 1973 6Hp Evinrude Fisherman hard starting cold

[Tom Bertulli]

Hi Phil,
Iv’e got about 5 hrs on the Nova type modules ( mine are Laser, house brand knock offs from Princess Auto – kind of a Canadian Harbour Freight store) and so far there is no problem. My electronics friends tell me that the burn out problem likely comes from old coils. The same older coils that will / may power point & condenser ignitions reliably, will cause these universal electronic modules to burn out. The explanation was this. Electronic modules watch the current rise as the magnet passes the coil shoes. The micro second that the current shows a drop, the modules interpret this as peak current and fire the spark. Modules like to see a rapid current spike cleanly without harmonics or fluctuations to the preset point when the spark will fire. Old coils which are beginning to breakdown internally produce a ripply current spike which points & condensers can tolerate well but electronics don’t like. With brand new modern coils the current spike is clean & rapid and the electronics work well. Both my coils had been replaced with new and had almost no hours on them. So far so good. Spark is hot, blue at about 3/8″ with a good pull on the starter rope. Now, if a coil is breaking down at higher RPM and causing a high speed miss – I’ll have to do a wire off test with the motor on the boat, to see if RPM drop is equal on each cylinder. Lakes are freezing here so that’s for next spring.