Classic/Antique Car Repair/Model A headlight


I have a 31 Coupe with the cowl lights. the headlights were flickering, so I purchased new ones. They only work with a ground wire attached to the reflector or bulb holder. I can't figure out the orientation for the bulbs. There are two filaments (32 & 50), and I know the orientation matters.

The longer filament goes on the top when the bulb is properly installed.
On the grounding issue, if the light tube is not tight to the reflector, and/or the connector tube to the shell is not a tight fit, you will have to install a separate ground wire from the light tube to the shell.  This involves the removal of the lamp and soldering a wire from the light tube to a new bolt attached to the shell.  There is a lot to this fix and it is explained on page 1-218 in the Model A mechanics handbook by Les Andrews.  You should have this book anyway, so get one.  About $35 from Snyders or any of the suppliers. Whatever you do, you must get a good ground to the light tube.  Make everything tight and test it with an ohm meter.  If you need more, let me know.  Good luck.  jack  

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jack bahm


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


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

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 and you will find them. Also, go to and search for "jackbahm" and you will find over a hundred videos. Many about the Model A and our outings. jack

"More than you need to know about cars." Just a small book for Car Nuts. "Model A Ford Tips and Hints" "Get A Horse" (What to do when Henry's Lady quits on you.) or Snyder's Antique Parts. "Engineering Stuff" (For the Kid who likes to take things apart and get them back together). Kids book for ages 10-16. 2012 Many Model A movies that can be found on

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. Go to this site for my Model A videos.

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