Removing External Regulated Alternator And Fixing Its Wire Harness On A 1971 Chevy C10

[@rogerveal1336]

Sensational video. Had everything except the brown wire. Testing with multimeter proved full 12 v with ignition on.

[@JR_406]

Funny this comes up as I'm chasing a draw issue on my Nova. Previous owner hacked the wiring for an internal regulated alternator with a physical switch to charge it. I removed that, put in a new alternator (like yours) used the one wire adapter that plugs into the regulator and screws to the bat terminal on the back of the alternator. It charges fine, but with the key off, it's powered and drains the battery. I've been trying to chase old wiring diagrams and figure out what i need to do to keep it from drawing power with the key off. Any ideas? I'm at my wits end.

[@RebeldryversGarage]

For some reason some people don't have any problem with battery drain with the jumper wire directly to the battery. Others do. See if the original brown wire is still under the hood. If so, double check it only has power with the key on. You can use it for the exciter wire.

[@JR_406]

@@RebeldryversGarage I'll have to do that tomorrow. I've been asking around and researching and some have said possible diode leak in the alternator. Even though it's new, we know what parts can be like these days. Thank you!

[@RebeldryversGarage]

@@JR_406 Ah yes. The good ole days when "brand new" actually meant it will work and work correctly.

[@JR_406]

@@RebeldryversGarage that's the truth. I think mine is a reman, but it's barely been used. I had a friend that told me he went through two alternators before he found a good one.

[@nursecuenca]

Great detail video. I tested my alternator on 65 c10 and it's not working properly. But from other videos they mention checking alternator fuse 1st prior to replacing alternator. Unfortunate I can't find fuse. My truck has 12v fuse box. Any suggestions would be appreciated. Thanks

[@RebeldryversGarage]

There is no fuse for the alternator, or the regulator on GM vehicles in the 60's. Start by seeing if there is power to the brown wire at the regulator when you turn the key on.

[@TheHiddenBooger47]

Could the brown wire, key on wire, be used for an electric water pump if also using with a relay ?

[@RebeldryversGarage]

Sure. using the brown wire to turn on a relay for electric fans or water pump would work fine.

[@RebeldryversGarage]

​@@davidcraft4909 I am not saying to power the water pump directly off the brown wire. It would be used to turn on a relay where the power wire to the water pump would be directly from the battery.

[@davidcraft4909]

@@RebeldryversGarage oh ok, I deleted the comment because I was wrong about that.

[@panchoperez8133]

Hi can't I do it on 1969 Chevy suburban C-10 let me know please

[@RebeldryversGarage]

Sure. I also did this on my 67 GMC as well.

[@TonyDechon]

So theres no ground wire hooked up on this?

[@RebeldryversGarage]

No. The alternator is grounded to the engine.

[@jairoquevedo5206]

I’m not sure what you did with the brown wire. didn’t see it in the video after u pushed it out the pigtail. I have a 1972 Chevy c20

[@RebeldryversGarage]

Sorry for the confusion. We used it to power the exciter wire R side on his alternator. His alternator was not a true 1 wire type. You can see it around the 9:32 mark. Thanks for watching.

[@isaaccervantes2462]

Does the alternator go screwed on to the original exhaust manifold?

[@RebeldryversGarage]

The alternator is mounted to the cylinder head in this application.

[@lbbass616]

What amp alternator did you use?

[@RebeldryversGarage]

I think it was an 80 amp. It was one I had sitting on the shelf from another project.

[@delljr2769]

Get American Autowire, full bumper to bumper harness with all new switches.

[@RebeldryversGarage]

Not everyone can afford the $575.00 for a complete wire harness. If the rest of the harness is still in good shape, rewiring the entire vehicle to solve something this simple is just silly.

[@adrianotso6443]

How does the alternator wire go in just red itself or with the wire connector

[@RebeldryversGarage]

The original red wire to the alternator is reused. It goes up the junction with the other 3 red wires, one went to the regulator (Which we cut out). One goes to the firewall where the backside of the fuse box to power it. The last wire runs across the radiator support to the battery that charges it. This is shown at 4.42.

[@elnoey]

Tkx

[@twmastert]

Tell me where the brown and red wires go

[@RebeldryversGarage]

The brown wire is powered with the key on, which means it is connected to the fuse block. I used it to connect to the exciter terminal on the alternator. The red wire goes from the alternator to the junction block next to the battery to charge the battery.

[@pnuts1649]

You have the exciter wire on the alternator (brown to red) and the charge wire (red original) ......... what are you using for the sense wire????? The way you have it wired your not really telling the alternator how much to charge. Don't thing that is going to work too well. Also, when using these old wire harnesses you should put in a circut breaker or fusible link between the battery and the junction block. Something GM should have done, when new. That charge wire in these old vehicles is pretty minimum and now you have increased the amps going to/from the battery and load with all the new devices being added to these old trucks. You should have increase the size of the wire from the alternator to the horn relay also with a higher amp alternator. I think you cut some corners doing it the way you've shown. Or am I totally wrong?

[@RebeldryversGarage]

It doesn't need a sense wire. Everybody does wiring their own way. And, everyone claims they are experts. This truck doesn't have AC, electric fans, power accessories, or a big sound system. The original wire works just fine.

[@pnuts1649]

​@@RebeldryversGarage Due to resistance in the charging wire caused by environmental factors etc., the voltage from the alternator drops by the time it reaches the battery. Just because the alternator is sending 14 volts doesn’t mean that the battery is receiving 14 volts. With Remote Sense, a second wire reads the actual voltage at the battery and signals the alternator to increase its voltage output to compensate for the voltage drop, ensuring a constant 14 volts at the battery. To say it doesn't need it, doesn't make it right to not use it. I can't comment on what everyone claims.

[@zx600e93]

I agree with Rebeldryver's Garage reply to this, and some of P Nuts too for good measure I'd recommend to the customer a fuse be installed between the battery cable to the junction block. Also, good question "..am I totally wrong? "and you bring up a good "spark" haha worth noting when upgrading the Alt w/higher Amps and important reason to ask & answer properly: Why do I need more amp. My soon to be installed (at design phase now) power hungry audio system prompted me here, and since the original electrical system was in fact over engineered to handle (way way back then) a wopping 50-65Amps on my oldy moldy, yes "cut some corners" (no ~A/C-20-21amp, non-OG sound sys, and others listed, and etc...) or removing the unneeded Amp mongers from this original design should not effect the existing devices. Awesome tutorial Rebeldryver's Garage, and very much appreciate your guidance & suggestions. One point though the VR connector is a brown wire not black as noted & corrected in 3:34 & 6:16. I've subscribed & liked this vid, can't wait to get my ride banging and determine what I'm going to do with that brown wire after upgrading to a 150Amp Alt. Thank you Sir, keep them vids coming, and to reciprocate I'd be glad to volunteer my Ed Tech background before final video production. Otherwise, I promise to pay it forward ;-) God Bless.

[@user-ge2qn6gp4o]

I have a question for you since I am getting conflicting information on different videos. I had heard that the brown wire was a sensor wire for the factory gauge. If that's not true do you know which wire is and how it would need to be hooked up for the factory gauge to continue operating? I am doing a very similar project on my 68 GMC. I purchased an 80 amp one wire from tuff stuff. A previous owner has already hacked a lot of stuff so I would like to remove most of the old systems wiring. I'd rather not run an exciter wire to the alternator if I don't need to. Can't I run the charge wire to an aftermarket distribution block on the core support, run one wire to the battery, then run the other wires (that need power such as main power, whichever wire is needed for the gauges etc)? This way I don't run a bunch of unnecessary wires everywhere while I am trying to clean up the engine bay.

[@RebeldryversGarage]

I am not sure how anyone could surmise the brown wire was the sensor wire for the Amp gauge. A wire sensing the voltage coming from the charging system would not have power with the key in the run position as it comes from the fuse box. Looking at my wiring diagram, the dash cluster harness has no brown wire for gauge equipped trucks. The brown wire to regulator is what powers it when the engine is running. Most of these aftermarket 1 wire alternators do not need an exciter wire to operate. Your idea to run a charge wire to the new junction block, then on to the battery, and back to power the fuse box will work. Since you are replacing the charge wire, I would suggest a 10 gauge sized wire to the battery.

[@SweatyFatGuy]

Good info, going internal regulated cleans up the wiring and makes thins so much easier. Hey man, here's a tip for making videos. When you're talking and explaining things, do it like you're talking to someone you know, like me for instance since you know me. When we talk you're natural and not self conscious, thats what I do. I think of someone I know that I am going to share information with that wants to know it. Still working on that, but it makes things a lot easier. I'll be moving cars from the farm all summer, so hit me up on FB messenger and I'll stop by. Maybe take the Cuda for a drive around Kearney. I need to do some work on it before I drive it up here, unless I trailer it. Depends on if I can find a driver or not.

[@RebeldryversGarage]

That can happen. But this truck is getting 14 volts at the battery. If the owner of this truck was making a bunch upgrades that were taxing the charging system, I would up the size of the charge wire to 10 or even 8 gauge. But, his set up is as simple as it gets.