I took this picture before I dug further into it, for reference when I went to put it back together. It looks like a dirt dauber got into the thing while it was in storage but other than the buildup on the condenser I didn't see any signs of insect trouble elsewhere and don't think that should have hurt anything. I noticed some blue-colored corrosion/build up around one of the holes through the regulator body but didn't get a picture and am now back at home without the parts in hand for a picture. Otherwise, everything in the case looks shiny new.
This is probably going to be of no use to you, but it is just my last experience with a one wire alt. I installed the alt. Started engine and revved it up per directions. ....Nothing just 12 volts. I repeated this several times with the same result. Then I took it for a drive keeping an eye on the gauge. And just like that as I was driving the gauge jumped up to 14.5 volts and the alt has been working great ever since. I don't understand but, it's all good now.
On the contrary... I learned I can take it apart and put it back together no problem. I was never gonna send it back, it was going to a local auto electric guy no matter what, I just really can't be bothered to wait 3 weeks to save $30 after shipping on a warranty repair. If I can crack the case open and replace the bum part myself, why not? What I'd really like to come away with is deeper knowledge on how to test these things so I can know exactly what to do next time. No dice here...
The insides look like a typical rebuilt alternator, with a mix of new and used parts. Everything appears to be where it should.
@trevorsworth It's apart, you are learning, you have the main culprit on order. You are doing fine. The toothpick or pin holding the brushes in place is the main trick to get it back together, so you've got that covered too. You now know more and if it works, you will have fixed it. If not, we can guide you.
If it doesn't work, you can buy an alternator for a 70s Chevy at the local parts store, and swap your special pulley onto it, and wire it up as a 3 wire alternator, and it'll work fine...and have a local warranty...and be something you can replace easily wherever you go, which means that it'll never fail.
If it's a true 1 wire it shouldn't need the jumper from batt. terminal to excite it. That picture is what someone might do to make a 10SI self exciting.
My take is that one wire alternators are a mail order item. Three wire 10SI alternators are available at all the local parts stores everywhere. It is not that difficult to wire a regular alternator one time and be done with the difficulty.
I recently went round and round on my 1wire falling to charge. After the 2nd rebuild kit I took it to at least 4 parts stores to test it. Only 1 store was able to run out on their machine, and it failed for everything that had been replaced twice. Found a local Alt & starter shop. He tested it and said the rotor was bad, which is rare. Long story short, forget about the parts stores and see if there is an alt shop in your area.
I followed “mad electricals” diagram for a 10si, I jumped two wires together, ran one to a bulb. Let the engine warm up (221 FH Ford) then blip the throttle, maybe 1200-1300 rpms, light went off, indicating charge, ammeter showed it as well.
What would happen if you jumped a one wire alt like a 2 wire? Would it hurt it? I ask because it is possible that the OP got a 2 wire by accident and he could test it by jumping the wires.
Shouldn't hurt If the #2 sensor terminal is accessible. That's how a one-wire is jumped internally --- jumper wire (red wire in pix) is hidden inside the case. Doesn't care if red jumper wire is outside the case.
10SI 12SI Delco Alternator 1 Wire Self Excited Regulator Rebuild Kit Chevy GM | eBay I used something like this to fix one years ago . The ground is really important also . Summit Racing SUM-1667 Summit Racing™ One-Wire Alternator Conversion Kits | Summit Racing you can convert a normal one to single wire also PREMIUM 1 WIRE CONVERSION KIT fits DELCO 10SI,12SI ALTERNATORS | eBay
Got my one wire from the local parts store. Ordered it for a forklift I think. I’ve never seen one in stock at the chain places. Exception would probably be NAPA Not 100a though. We did a one wire rebuild/convtsion from an e-bay kit in another project. Did well. It’s getting hard to find a 10si at the boneyards. A few years back I started not turning em in for cores just to have a couple on hand.
Not that hard to find a one wire alternator either if you ask for one for a tractor. I agree 100 % that it isn't that hard to wire a standard 3 wire alternator that you can find everywhere for as little as 35 bucks rebuilt. The street rod magazines screwed with guys minds back a few years ago with the Clean no wire showing NOT TRADITIONAL engine compartment thing and got the one wire nonsense started. You could walk into most farm equipment dealers or farm country parts houses and buy a one wire alternator to put on your 9 N Ford tractor or Farmall , older diesel or Oliver tractor that ran a magneto ignition long before STREET RODDERS decided that they could get out of hiding two wires on the engine if the alternator only had one wire to begin with. That is the only frigging value of a one wire alternator on a gas powered non magneto ignition car or truck that is street driven. Mag ignition tractors don't have ignition systems except the kill switch. When you buy a one wire alternator you are not buying a hot lick street rod item you are buying something designed to be used on a farm tractor that does not have an ignition system to run an exciter wire from clear and frigging simple.
So ? Hotrodders use things from all sorts of sources , it's part of the deal,, if it doesn't suit your sensebilities , that's fine .
I save every applicable alternator wiring diagram I find (including some posted on the Hamb) here https://photobucket.com/bucket/c5e8...74/album/694af3ea-994a-4ac7-af37-2e4f6ad7da37 for reference. Several are just different ways to hook up a 10 or 12 Si alternator or different looks at the same way that some might understand either than others. Still for me there is only one legit and viable reason to stick a one wire alternator on a traditional rod or custom and that reason is that you are on a road trip to or from something fun with cars and your generator craps out and there is no generator available without a big expense for getting one delivered by the brown truck with a red label on the package the next morning at an exorbitant cost but that farm equipment dealer or the parts house in that little town has a one wire alternator that you can stick on in it's place and with not much more than a length of wire and a couple of wire terminals, a roll of tape and a different belt if needed you can be on the road again and deal with the generator when you get home.
I went with it because it was available and tied straight into the stock A wire harness... not because of any street rod mumbo jumbo. I have 3 generators in my possession, one of which is on my rod and two of which are dead 6v gennies. For this work truck I'm ok with an alternator - I want to be able to run accessories, charge my phone, etc. The new regulator did not fix the problem so I'm taking it to my auto electric guy and he can tell me what's wrong with it.
Sort of. A normal 3 wire hookup wont use the jumper from battery output terminal. Usually use a switched 12v. off the ignition switch so that terminal isn't always hot. The drawing is the shortcut guys do.
This picture isn't new, but installing a temporary charging light circuit as Budget36 points out may help troubleshooting. Have you checked belt tension, and if all connections have good continuity? Rusty/oxidized ground connections on old cars always cause issues.
I’ve been using this one for 5 years including the I-did-it light. I believe it’s a PowerMaster instruction sheet!
Not always a "short cut guys do"; couple '80s GM cars I had were factory wired with the battery to terminal 2 jumper.
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