Mystery Magneto

[jwilli43]

I have this big old magneto and I'm trying to figure out what is goes to. It has a lot of stamping on the front cover. It looks like an Aero #649. It has 6 lugs on the back for spark plug wires and a keyed shaft out the front. It weighs 10 pounds. Anyone know what vintage or what cars it would fit? Thanks.

[Craig Gillingham]

Definitely a Splitdorf Aero magneto, Splitdorf is the make and Aero is the model of magneto. I'm not sure why there are two terminals on the point cap, I'd guess one is to short the magneto out, don't know about the second one.

I've looked through some books, and possible 6 cylinder cars that used Splitdorf ignitions in the 18-24 period were the Ferris, National, Mercer, Roamer...

I also don't know if Splitdorf made just magnetos, or distributors as well, as the references only say Splitdorf ignition systems. And I don't know which cars used clockwise or anti-clockwise rotations, which could also narrow down what car this could be off.

Unless this is off a truck, then I've got no idea what it's off.

I think the Splitdorf Aeros were used from about 1919-1920 onwards, at least the Aero magnetos used on motorcycles were.

I hope this is off some help, and hopefully someone can add something else.

[Ivan Saxton]

The second connection though the points cover is for a wire from the starter switch, so that when the starter is cranking, the magneto is supposed to give a very hot spark for easy starting. A couple of old auto electricians have been less han enthusiastic about this feature, without giving me a plausibl explanation. The magneto design itself is at face value a high quality principle as far as I am concerned; because the power of the spark should not be altered or dependant on advance or retarding the timing. I have had the coils rewound for mine with modern materials. The magneto cannot seize because the insulation of the widing has perished, liquefied with engine heat, and set hard to prevent rotation when it cools. While my magneto has excellent spark on the bench, often it just will not fire on the motor. So it has an illigitimate Simms on it for now. These magnetos are also known as Dixie .