Owen Dyneto 40300

[pughs]

Here are some pictures of the the Owen Dyneto 40300 that is currently on my car (and doesn’t work) with the Autolite 21732 sitting next to it. Although they look identical to me could there be less than obvious differences that would make them not interchangable?

 

 

[edinmass]

The Autolite will work fine, has a different shunt. I have used the identical unit on many cars. They were reproduced until fairly recently. Some were made of Chineesium. Those seems to work well. The original units are just about impossible to find. There is one good guy who can service them in Massachuetts.......AJ knows and lives near him. As you know, EVERYTHING about that unit is IMPOSSIBLE to find, and difficult to service. Use caution when servicing it......or it will bite you in the ass. 

[pughs]

Ed,

What is a shunt and how do the shunts differ between the two regulators?

[edinmass]

The shunt is the external resistor with the wire wrapped around it. Basically it controls charging rate using the temperature of the wire to increase resistance and cut back battery charge. Ultimately the cut back is somewhere between 25 and 40 percent. For 99 percent of people driving today it won’t make any difference. The cut out portion is basically identical across them all. The unit is used on four cylinder Indian Motorcycles to Packard, Pierce, Lincoln, Cord, and countless others. 
 

Think of a shunt as a faucet that self controls itself from wide open to 60 percent. Thus at cold engine start up, your generator will charge 22 amps, as the shunt gets to engine operating temperature the increased electrical resistance cuts back power to the field coils, and the generator puts out less power. Probably not the correct engineering nomenclature or explanation, but it’s how it works. Orin.....please chime in.😝

 

 

Edited July 31, 2021 by edinmass (see edit history)