10si alternator

[67c10-355]

I have a 72 c10 that now has a 10si alternator and i need to know how to wire it to bypass the factory external voltage regulator. If someone can provide me with a wiring diagram it would be a huge help.

[fixit-p]

Here's a diagramon the 12SI same as 10SI. Do you have ammeter or dummy light?? If you have an ammeter verify voltage on the brown wire at the regulator connection there needs to be rsistance on that circuit IIRC the original wiring light or meter has this resistance built in (just to verify).

[67c10-355]

Is there an easier way to run the wires? Like the number 2 wire from the alternator straight to the the battery terminal on the back of the alternator. and then the number 1 straight to the warning light

[ERASER5]

Is your harness factory or is it already hacked up? If it is hacked up, read the thread Alternator upgrade 3 wire. read and follow the linc for diagrams.

If your harness is factory, the switch from external to internal regulator is extremely simple. Look at the diagram on this thread. Make two jumpers with female spade connectors. At the old regulator plug jump 1 to 3 and 2 to 4. Start at either end, it will be the same. For the alternator end, the ground is not needed. Clip it off neatly. The large red wire is reused as it is. Fro the plug, you need a flat plug to replace the square plug. The neat way to do this is to go to AutoZone (or any other box store) and get a flat alt plug. Using a small screw driver, depress the retention tab on the connectors and slide them out of the plastic. Do the same for the original square plug. Now slide the original connectors into the new flat plug. Now here is the tricky part. Did you get the correct wire to the correct alt connection. The check is simple. Your neg battery terminal is off right? Just slide it on. Do not tighten. Not start your car. Now shut it off. Did it keep running? If so, pull the loose neg terminal off again. Pull out the flat alt plug and swap wires. If the car shut off, then you got it right. It took way longer to write this than it does to do it. I did mine in like 5 minutes.

[54blackhornet]

MAAD Electrical has a great explanation on how to convert from original to internal regulator.

[RustyPile]

Originally Posted by 67c10-355

Is there an easier way to run the wires? Like the number 2 wire from the alternator straight to the the battery terminal on the back of the alternator. and then the number 1 straight to the warning light

Installing those two jumpers per that diagram IS the easiest way to do it.. Takes all of 5 minutes.. Yes you can remove the original voltage regulator plug and route the brown wire directly to the alternator. BUT.... The blue wire in the diagram is the voltage sensing wire for the internal regulator.. it needs to terminate some distance from the alternator.. The voltage falls off a small amount as the distance increases from the alternator output post, so by sensing at a distance allows the alternator to raise the voltage detected at that point.. Sensing the voltage directly at the alternator is not the optimum location.

[tdangle]

the above diagram is what I did last week. Worked perfect and very easy. I soldered the wires and used heat shrink, Although you could use crimp connectors also