Classic/Antique Car Repair/Ammeter readings

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Expert: - 7/28/2010


Question
Should the ammeter ALWAYS show a charge ? or does it only show charge according to draw ?

Answer
The ammeter should show a charge when it can overcome the draw and the engine is reving.  If you have no load on it, it will show a high charge rate, but as you load it up, the rate goes down and if you put too much of a load on it then it will show a discharge.
We run alternators on our cars and we don't have a problem with keeping the batt up.  There is no regulator on the old generator.  It puts out what it can, depending what you have it set for, and it will show a positive charge until the load exceeds the output.

jack

Classic/Antique Car Repair

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jack bahm

Expertise

Only repair type questions on the 1928-1931 Ford Model A.

Experience

Owned one when I was 15 yrs old, and now have owned 5. Still own and play with 2 of them.

Organizations
Oakleaf region of MARC. Model A Restorers Club. I have put several Model A videos on the Oakleaf site that may be of help. Things like how to start the A, how to Time it, how to troubleshoot it.. Go to oakleafregion.org and you will find them. jack

Publications
"More than you need to know about cars." Just a small book for Car Nuts. Blurb.com "Model A Ford Tips and Hints" Blurb.com 2010 Many Model A movies that can be found on youtube.com/jackbahm

Education/Credentials
BSME LSU, 1958, Masters of automotive engineering from the Chrysler Institute of engineering, 1960, MBA Mich State, 1976. Worked as an engineer at Chrysler from 1958 to the end of 1991.

Awards and Honors
Two patents while working in auto industry.

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