What would happen if you had a one wire alt and wired it like a three wire. I "ordered" a three wire alt from moon awhile back and wired it accordingly. I am having issues with the battery not charging but the alt is not bad, and I am wondering if I could have a one wire instead. If it was would it not work if wired like a 3 wire?
If it is the older Gm style,it should have a rubber or plastic plug covering the field terminal. All you would have to do is run a 12v. wire to the stud(preferably 10-12ga.wire). When you fire the engine,take it up to about 1400 rpms to excite it and it should charge.
the exciter wire should be a "hot, ignition on" only or it will drain your battery in short order. other than the wire back to the battery (mine runs to the battery terminal on the starter relay) the exciter wire is the only one needed for a "three wire" alt
I have a Chiltons from 62-68. It's a later one with an internal regulator. I nwas jsut thinking it was a one wire sent by mistake, and I am wring it like a three wire, if that made a difference. Maybe I have it to the wrong post on the ign switch.
What kind of alternator? Is is a GM SI10 or 15 or the like? If the alternator tests OK, it should be a simple wiring fix.
Is the battery in good conditon Dooley?Also,is the Alt rated at enough amps to charge the size of battery you got there?Just trying to cover all the bases.Let us know how you get on.Cheers.Kol.
The battery is new and at it is taking a full charge. Each time I run the motor it loses it's charge, and it shows discharge on my ammeter, esp when I click the electric fan on. I have it wired with a 10ga wire to the ammeter through and to the starter. The pin furthest away is jumped back to the batt port on the alt, the other goes to a (hot when the key in on) source on the ign switch. It's a late 70's 80's model. Not sure what number it is. Supposed to have been rated at 61 amps. The only electric I have wired is the fan, and a fuel pump.
You got it wired wrong. You should have a wire from the regulator plug through the ammeter to a hot with key on. Main battery connection to the battery or preferably a junction block or the solenoid and the other regulator plug to your main power junction block for remote voltage sensing so the alternator will charge properly. Check out this link for a good drawing. http://alanhorvath.com/54chevy/mad_electrical.php
This sounds like you've got a GM SI10. It should charge at very low RPMs. I used one on a 12V conversion on a 52 8N Ford tractor. So you shouldn't have to rev it much for it to charge. The SI12s take a bit higher revs before they kick in. First, I'd recommend losing the ammeter and using a voltmeter instead. It gives you a much better indication of how your electrical system is operating. I'd also try running that 10-gauge charge wire straight to the battery's positive terminal, just to be sure. Usually on the two-pin connector on the alternator, terminal 1 is field connection and the 2 is the voltage sensor. The field connection lets you use an idiot light. But you don't need the idiot light if you use a voltmeter. I don't know exactly what you mean by "The pin furthest away is jumped back to the batt port on the alt." Maybe 1 & 2 got flipped, and the voltage sensor wire ISN'T the one that's run to the hot terminal on the ignition switch. Hope this helps.
According to all information I have it is wired correct. However there is not a lamp or resister in the wire that goes to the ign swich(hot whne on) Do I need some draw to start the alt to charge?
Have you measured the voltage at the battery yet with it running? If not, go do that now. If you are not seeing at _least_ 13 volts, your alternator is not putting out, or you have a wiring problem. I'll add, lose the ammeter. One less variable to contend with, and a voltmeter will serve you better overall on the diagnostic front. Alex.
Not hyjacking, but I guess I have never thought about it, but why is there the term "FIELD"??? I understand one heavy wire goes to the batt. for charging, one crosses over to excite the alt, (and why didn't the manufacturer just do that inside the alt).??? and one goes to the guage (amp/volt meter). what is the FIELD for??? maybe a ignorant quest. but I don't know the answer...Ken
In the case of a '3-wire' there is no field wire. You have a BAT (output) a Sense (#2, jumpered to the BAT) and Lamp (#1, for you guessed it, the lamp, not required for alternator operation incidently). As for field, it relates to how the alternator creates electricity. The rotor is powered to create a magnetic field (hence field current; the juice going to the rotor to create the magnetic field) which in turn creates electrical power in the stator as the rotor rotates. Alex.
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