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Charging System Question

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60Bugeyefan

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I have changed out the battery and voltage regulator (pre-adjusted from Moss) this weekend. I get a consistent 12V w/ no lights but this drops to 11.5V or less with turn signal or headlamps. I tested the generator per the manual and am able to generate at least 18V at 3000 RPM. While driving on the open road I do not see the voltage ever higher than 12V and never see the ammeter above 0 but it will drop with turn signal or headlamps on. Based on what I have read online, I believe I should see the voltage of 12.6V-13.5V while driving and the ammeter slightly above 0. My next thought is to change out the brushes on the generator. I have checked continuity between the generator and regulator and it tests out fine. Any thoughts?
 
Look in the manual and learn how to correctly adjust the regulator- Moss is good but not always perfect.
BillM
 
Keep in mind--the generator won't put out much until you're up to about 1800 RPM, plus or minus. It probably won't provide enough current to run the car at idle; that is, the ammeter will not be in the "charge" range. But, yes, at higher speeds you should see a system voltage of 13V or so, and unless you have a lot of electrical stuff turned on, the ammeter should show at least a small charging current.

By testing the generator, do you mean that you jumpered the output to the field coil terminal and disconnected it from the rest of the electrical system? If so, I'd expect something higher than 18V at 3000 RPM. If the generator was still connected to the electrical system, though, that might be OK.

Did you check belt tightness, and make sure it's not slipping?

If you check the regulator per the manual, be sure to use a decent-quality analog voltmeter. A digital meter won't work. Oh, and on the subject of meters--if you're using one of the simple automotive voltmeters from you local auto store, it might not be working right.
 
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