I have a 1972 100HP V4 Evinrude. I notice that the 100HP and 125HP (as well as the 85, 55 and 60HP) models between 68 and 72 seem to use one of two specific power pak models available for that series motor. For example the 1972 100HP uses Sierra 18-5748 where as the 1971 uses 18-5749.
Similarly between 1968-1972 other motor sizes (55, 60, 85, 100, 115 and 125) in those years use one or the other of these two models. A similar split is seen in the CDI and other after market brand replacemet power paks.
All of these motors seem very similar, what is so different in thier ignition systems that required two slightly different power paks during the 68-72 years? They all seem to use CD amps where the ignition and charging systems are independent of each other. Are these two power pak models compatible with each other- or will the power pak fry or not work if you put for example one made for the 1971 series in the 1972 or vice versa?
If I'm ever looking for a used power pak in the future I wanted to know this so I know what units I could put on my motor.
Similarly between 1968-1972 other motor sizes (55, 60, 85, 100, 115 and 125) in those years use one or the other of these two models. A similar split is seen in the CDI and other after market brand replacemet power paks.
All of these motors seem very similar, what is so different in thier ignition systems that required two slightly different power paks during the 68-72 years? They all seem to use CD amps where the ignition and charging systems are independent of each other. Are these two power pak models compatible with each other- or will the power pak fry or not work if you put for example one made for the 1971 series in the 1972 or vice versa?
If I'm ever looking for a used power pak in the future I wanted to know this so I know what units I could put on my motor.