Capacitor On Alternator

[stan5686]

There is a Capacitor, John Deere part #AL30423 on the back of the alternator on my 2950. Does anyone know what this is actually for? I am having a problem getting one and I'm not sure if it affects charging. I read one place that it is for the Tach. another that it would be for cutting down on noise in the radio of cab tractors which mine is not. Thanks for any help!

 

[mmancuso13]

It helps maintain current in the secondary winding...

How does a capacitor-assisted alternator work? - Worldpowerfaqs