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One Wire Alternator Info

Thanks to Wayne Petty for most of this info.

If you have a 1 wire alternator in you street rod, custom or daily driver are you aware that parts for these are not stocked in most parts houses? I found this out last year when mine quit in Prescott, Arizona while I was on a trip and couldn't find the parts I needed in a town with over 10 parts houses.


The 1 wire is basically a 3 wire GM alternator (Delco) with a self-energizing voltage regulator. Herein lies the problem. Most parts houses don't stock the self-energizing voltage regulator. I would strongly recommend getting one and carrying it with you. They only cost about $6-$8 and take up almost no space. If you have one you can put it in a 3 wire alternator that you can buy almost anywhere and convert it into a 1 wire or if yours goes bad in your 1 wire alternator you can replace it.


If you want to get the parts that will probably fix 90% of your problems then have your parts house order the following parts if they don't stock them.


For the following parts check: Transpo Electronics


the d10se 12 will convert a 7127 alternator to a one wire alternator
you might also change out the lower parts... as these are better...
that what most rebuilders put in... I usually tell my customers to
buy a cheap rebuilt 7127 and tear it apart and install the new
componants.,..
d10se12 is a internal one wire regulator...

dr5042 is a heavyduty rectifier bridge...

d528 is a quality diode trio...


the d713L will convert your alternator to a one wire alternator...
the D7014 will also convert your alternator.... but it uses a box that must be attached to the back of the alternator...the 713 just plugs in and stays there...


The Following are all ACE part numbers -- Salt Lake City warehouse (801) 972-3796 & (800)451-1396 -- Phoenix warehouse (602)272-3800 & (800)742-8400. The one to get if you only get one is the VR1770SE:

VR1770SE (alternate part number is D10SE12)--Self energizing 14.1 volt regulator ($4 to $6). Works best with average battery.

S1390--Diode Trios for most normal size Alts. ($2)

S1375L--Rectifier Bridge with 200v 50 Amp diodes ($6 to $8)

Second Choice for the volt regulator is:

VR1786SE--Self energizing 14.8 to 15.3 volt regulator. If you run a Delco sealed top battery it will accept the higher voltage and you headlights will be brighter, but may not last as long


If you get a 7127 10si alternator these are the parts that you will need to built it to a one wire alt..

ace VR1770SE voltage regulator (try to get the ace version )
ace S-1375L rectifier bridge long life. with 50amp @200volt diodes instead of 25A@100volters only a buck more .
ace S-1390 diode trio

the VR-1770SE regulators are self energizing and will control the alt light. by just hooking up the correct wire .

I do recommend that you use 10 gauge or larger wire (10,8,6,4 gauge,) from the back of the alt to the battery..


The above information came from Wayne Petty. Thanks Wayne.

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