This is on my carbed motor swap 91 Lincoln. Put a 1 wire alternator on it. Bolted it in and ran a brand new cable and connectors to the battery positive. I tested the alternator at the parts store and it was fine. Its only making 11.8 volts at the alternator no matter the rpm...... Not sure of this will help but this is the wire layout for the battery. Two positive cables go to the starter and the other to the starter relay right next to the battery. Negative goes to an engine ground and another from the negative terminal to the chassis. Can't figure it out. Any help appreciated.
Try running a ground directly from the chassis on the alternator to the firewall and not tying it into anything else. 10AWG wire at least.
Just attempted that and no change still 11.7-11.8 volts at the alternator. Stupid question but is an alternator multi directional......like could it actually be turning the wrong way or does it not matter.
I'm at a total loss now. I think I've tried everything short of ripping everything out and starting everything from scratch.
make sure you start and rev the engine , some alternators need to be up in rpm before they excite and start generating. alternators are omnidirectional, sense its ac and dc rectified. if its a true 1 wire alt it sounds like its bad. if its an alt that has an exciter wire, then you tie that to your output post and it should come backup to 14ish volts. post pic.
Had a new one once that would test at 13+ volts when I would first start it cold, but after it would run a few minutes and warm up, the voltage would slowly drop down below 12volts without running any accessories. Never figured out why. Exchanged it and all was good.
Will start and give it some rpm today If that doesn't work I will take it back and try another one. It is a true 1 wire no Excitor post. Thanks
Well for whatever reason it worked yesterday after making no changes. Maybe it was the rev...... either way I appreciate the help guys.
remember ,if your going to run fuel injection , get a newer style alternator, fuel injection requires an alternator that runs higher voltage at lower rpm.. most efi's require a minimum voltage to operate correctly.
Maybe on aftermarket systems but a old OBD-I Ford system will run happily on 12v... My '86 Grand Marquis & 5.0 Stang both had 65A 2G alt from factory and ran fine(even when alt was dead)... The 2G is nothing more than a 1G with internal regulator...
