Fifth Avenue Internet Garage

Tech Tip Archives

Just like with anything...if you spend enough time doing it you tend to get good at it, and you learn a few shortcuts to make your life easier. Having spent twenty plus years solving electrical, cooling, and fuel related problems on all types of antique and classic vehicles, I have "earned" a few tech tips that I want to share with you. Check back often, as I will keep adding to the list as time allows. For more tech tips, check out the Tech Tip Archives.

Randy

Early 1950'S Buicks With Brush Protected Generator

This was a protection device designed by Buick engineers to protect the armature inside of the generator from excessive brush wear. When the generator brushes were 80% or more used up the car would fail to start. Buick simply ran the ignition circuit thru the charging system. The Field circuit was used to ground out the ignition circuit preventing the car from starting if the brushes were worn to a point the wire inside of the brush itself could make the contact. Some Buick car owners carried a jumper wire in the glove box to by-pass this circuit in order to drive the car to the dealership for service.

When installing an alternator on a Buick with this "feature" you simply need to find the field wire that is grounded...(found next to the regulator, and is grounded using a sheet metal screw... ground to the body). and connect it to the yellow "exciter" wire coming from the alternator, thus making it a hot wire to complete the ignition circuit.