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kenparker0703 · 12-18-2020, 01:10 PM

Not all alternators perform the same way. Lets assumeyou have a GM -1 wire, which is probably the most common adaption. Some will not even kick in and produce electricity until your engine reaches about 1000 rpm. Some kick in at idle (about 600 rpm). Others cycle in and out.
The igniton circuit of the Model A (6 or 12 volt) only uses 1 to 2, maybe 3 amps. The needle will barely wiggle, which is hard to read on the amp gauges.
Check it this way. Start engine. Rev up to 1000 rpm or more - momentary. Watch needle - see if it wiggles.= when the alternator engages. If it does not move turn on the headlights and watch needle. It should move to discharge- about 10 amps and them move slowly back to 0 amps.

If it stays at 10 discharge, alternator is prolly not working. If it moves back to 0 then alternator is recharging the battery.

Clear as mud?????

12-18-2020, 01:10 PM	#2
kenparker0703 Member Join Date: Sep 2018 Posts: 88	Re: Alternator Hasn't Kick In Not all alternators perform the same way. Lets assumeyou have a GM -1 wire, which is probably the most common adaption. Some will not even kick in and produce electricity until your engine reaches about 1000 rpm. Some kick in at idle (about 600 rpm). Others cycle in and out. The igniton circuit of the Model A (6 or 12 volt) only uses 1 to 2, maybe 3 amps. The needle will barely wiggle, which is hard to read on the amp gauges. Check it this way. Start engine. Rev up to 1000 rpm or more - momentary. Watch needle - see if it wiggles.= when the alternator engages. If it does not move turn on the headlights and watch needle. It should move to discharge- about 10 amps and them move slowly back to 0 amps. If it stays at 10 discharge, alternator is prolly not working. If it moves back to 0 then alternator is recharging the battery. Clear as mud?????