The Ford Barn

daveymc29 · 05-31-2018, 04:24 PM

I have a 29 coupe pretty much stock with 6V pos. ground electrical system. I got it running and noticed that the amp meter showed hardly any charge at all when I drove it so I tried with the moveable brush and got it to register a couple of lines on the plus side. Not so sure as it sits at about two lines neg. when everything is off. I had a couple of 6V neg. gr. alternators and installed one. If I wound the engine up a bit it would eventually put out some pos. reading. Not so much without spinning it to get it excited. Today, after having not been driven for a couple of weeks I went for a test drive after some brake adjusting and when I started the car it fired right off. Not into the plus side without revving it a bit, then it seemed happy and I drove a few miles and noticed the ammeter was back at its normal spot about 2 lines down. Turned on the lights and it went down several more lines and no amount of revving would bring it back up. It appears the alternator has quit functioning. I'm no electrical guru but have two other A's with the same set up and when I start them up they immediately begin to charge for a few minutes and then rest a line or two + after the battery has regained what it spent cranking. Where do I start to look? Don't want to put another alt. on there and have it die also. All are using the same size two inch pulley.

05-31-2018, 04:24 PM	#1
daveymc29 Senior Member Join Date: Sep 2010 Location: Danville, CA Posts: 1,566	puzzled I have a 29 coupe pretty much stock with 6V pos. ground electrical system. I got it running and noticed that the amp meter showed hardly any charge at all when I drove it so I tried with the moveable brush and got it to register a couple of lines on the plus side. Not so sure as it sits at about two lines neg. when everything is off. I had a couple of 6V neg. gr. alternators and installed one. If I wound the engine up a bit it would eventually put out some pos. reading. Not so much without spinning it to get it excited. Today, after having not been driven for a couple of weeks I went for a test drive after some brake adjusting and when I started the car it fired right off. Not into the plus side without revving it a bit, then it seemed happy and I drove a few miles and noticed the ammeter was back at its normal spot about 2 lines down. Turned on the lights and it went down several more lines and no amount of revving would bring it back up. It appears the alternator has quit functioning. I'm no electrical guru but have two other A's with the same set up and when I start them up they immediately begin to charge for a few minutes and then rest a line or two + after the battery has regained what it spent cranking. Where do I start to look? Don't want to put another alt. on there and have it die also. All are using the same size two inch pulley.