[braz28]

I am considering converting my 1969 3 wire external regulator to 3 wire internal regulator. I have a few questions :

1- can i re-use my stock 1969 alternator fan and pulley.
2- will the 3 wire internal regulator alternator re-use the stock 1969 mounting brackets.
3- Which year/ model of car/truck do i ask for at auto parts store for 3 wire internal alternator

4- where can i find the wiring instructions for converting to internal ( i would also want my in-dash light to function).

I have read the MAD electrical conversion kit, but i live in Canada and it would take a few weeks for me to receive the kit, so i would prefer to make wiring modifications myself and be able to enjoy my car sooner.

thanks

 

[Eric Kammerer]

If you do a search on "internal regulator", you will find all you need. Including this excellent tech article on how to do the wiring.

http://www.camaros.net/techref/ftecref14.html

Answers to 1 and 2 are yes with a 10SI alternator, answer to 3 is to see which clock position the plug is on the existing alternator, and go to a good parts store and ask for a 10SI with same clock. Can also go online to someplace like RockAuto.com and go through the catalog for some mid 70s GM application (I use mid 70s Corvettes) and look for an alternator with the correct clocking and highest amp output (63A for an OE replacement 10SI, can get higher amps with an aftermarket unit).

 

[Eric Kammerer]

More good info found by searching "10SI" here:

http://www.camaros.net/forums/showthread.php?t=111077&highlight=10si

 

[DOUG G]

I used the 89? Pontiac Safari 130CS 105Amp alternator... no pulley swap needed :noway:

 

[braz28]

thanks for all the info,

I got the 12si alternator installed.

Car will only turn and wont start.

The only way it will start is if i remove the 2 wire plug on the alternator, once car as started i can re-install the alternator plug and alternator starts charging and engine will remain running.

Following is how i wirred the new alternator.

+ from alt to + on Battery

#2 terminal to + on alternator

#1 terminal to brown wire that feeds the idiot light

 

[DOUG G]

http://www.camaros.net/techref/ftecref14.html

When you convert from the external regulator alternator, you no longer need the regulator that is mounted on the radiator support. You also don't need some of the wiring that is present in the loom.

The diagram below shows the original connection at the old regulator. (I'm sorry, but the wire that is colored yellow, is really white)

The next diagram shows how you modify the loom at this location.

Notice that the blue wire is jumpered to the brown wire. The white wire and the orange wire are just capped off so that they will not short out to anything.

This next diagram shows what you have to do at the new alternator.

The wire that goes from the "BATT" terminal to the #2 terminal is a new wire that you will have to add. You can use a 14 gauge wire.

The white wire (shown yellow) just gets capped off.

You will need a new connector to fit the new alternator and they can be purchased at almost any auto parts shop.

Due to my being bothered by the "extra" wire being in the loom, I totally removed the dead white and orange wires. I also wired the brown wire to the alternator directly. It just gets rid of some extra length of wire.

The prior paragraph has caused me a lot of e-mail feed back and hopefully the following information will clear it up. In my final wiring configuration, the "brown wire" comes from the alternator indicator light, through the firewall connector, and directly to the alternator. The result is electrically the same as the diagram at the top of the sheet, just cleaner. The diagram above would have the brown wire coming out of the connector at the firewall, going toward where the regulator was, connecting to the blue wire, then the blue wire goes to the alternator. As I said, I cleaned up the wiring (and in the process, dirtied up the wording).

In order to ensure good connections, I recommend that you always solder the connections and then use heat shrink tubing to seal it.

 

[braz28]

http://www.camaros.net/techref/ftecref14.html

When you convert from the external regulator alternator, you no longer need the regulator that is mounted on the radiator support. You also don't need some of the wiring that is present in the loom.

The diagram below shows the original connection at the old regulator. (I'm sorry, but the wire that is colored yellow, is really white)

The next diagram shows how you modify the loom at this location.

Notice that the blue wire is jumpered to the brown wire. The white wire and the orange wire are just capped off so that they will not short out to anything.

This next diagram shows what you have to do at the new alternator.

The wire that goes from the "BATT" terminal to the #2 terminal is a new wire that you will have to add. You can use a 14 gauge wire.

The white wire (shown yellow) just gets capped off.

You will need a new connector to fit the new alternator and they can be purchased at almost any auto parts shop.

Due to my being bothered by the "extra" wire being in the loom, I totally removed the dead white and orange wires. I also wired the brown wire to the alternator directly. It just gets rid of some extra length of wire.

The prior paragraph has caused me a lot of e-mail feed back and hopefully the following information will clear it up. In my final wiring configuration, the "brown wire" comes from the alternator indicator light, through the firewall connector, and directly to the alternator. The result is electrically the same as the diagram at the top of the sheet, just cleaner. The diagram above would have the brown wire coming out of the connector at the firewall, going toward where the regulator was, connecting to the blue wire, then the blue wire goes to the alternator. As I said, I cleaned up the wiring (and in the process, dirtied up the wording).

In order to ensure good connections, I recommend that you always solder the connections and then use heat shrink tubing to seal it.

thanks these are exactly the instructions i followed from the tech archives.

For some reason, when the alternator connector is installed i do not have 12v to the coil, if i unplug the alternator connector, the car will crank and start, i can proceed to re-install the alternator connector and engine runs perfectly with the alternator charging.

I had same problem a few years ago, if i left the radio on while tring to crank, i had to turn off the radio to get 12v to the coil. i replaced the radio and problem went away.

any ideas

 

[braz28]

update!!!! i reversed the #1 and #2 wires and the engine starts, idles and charges.

What i find curious is my ignition 12v is now wirred to #2 and batt is wirred to #1.

 

[DOUG G]

Glad its all working now... I hate electrical gremlins

 

[Greg O]

Doug, I believe the diagram you showed is for a CS130 conversion? He has a 12 SI.

Braz28, Wiring a 12SI is very easy. Don't run the bat+ wire direct to the battery. It should go to the horn relay buss bar. Upgrading it to an 8 awg is a good idea.

At the voltage regulator connector you can run a jumper like this.

Here is a complete wiring diagram.

At the alternator connect the factory blue wire to terminal 1 and the white to terminal 2.

 

[DOUG G]

Greg, I was told the wiring is the same except the plug at the alternator.

 

[Greg O]

If you have a 12 SI you can put the sense wire (2) on the bat terminal but it will significantly decrease the system performance. The output will be set to deliver 14.2 volts at the bat terminal on the alternator, but over at the horn relay it will be less due to voltage drop in the wiring. Any electrical accesory you add to the system will be "invisible" to the alternator as it is down stream of the sense wire. Therefore you could get greatly reduced power to the accessory and certainly to your battery.

If you wire an SI like the diagram I posted you will have voltage sensing at the splice. The result is 14.2 volts at the horn relay and maybe 14.7 or more at the back of the alternator. When you power that 25 amp fan to the horn relay, you maintain 14.2 volts at the relay because the sense wire detects the extra drain and increases alternator output.

Probably splitting hairs if you don't have a lot of electrical accessories but my thoughts when I did the 12SI conversion were might as well do it optimally while I am at it.

 

[68problemchild]

1. Can someone identify what the blue, white, red, brown, wires on the relay each go to?

I am trying to remove the relay and incorporate a new alternator. My L92 engine is already wired so its non standard set up.

2. Also, my sensing wire appears to be on the alternator stock. I take it this is bad?

Thanks.

 

[Everett#2390]

From ext reg connector:
Blue was field voltage to ext alt , #2 terminal.
White wire, #2 on ext reg, went to #1 terminal on ext reg alt.
Brown wire comes from GEN light and other side of GEN from ign switch.
Red wire from ign switch, resistive wire, providing a parallel path from ign switch if GEN light bulb burned out.

Voltage sense wire should go to, I would think, to BAT spade on OE fusebox to monitor electrical load. You should have sense wire at the end of the power buss line/bar as accessories between alt BAT stud and the end of buss line draws power, lower voltage sensed at the end of the buss line, thus alt generates more power to make up for the demand. Make sense?

 

[68problemchild]

So:
1. I cap off orange and white.
2. Connect brown to blue.
3. Run jumper from batt junction box to horn relay?

Voltage sense wire down stream of load. Makes sense.

Harness designer said wire on Alt was to power the fusebox.

I am getting there....

Thanks!!!!

 

[Everett#2390]

So:
1. I cap off orange and white.

I'd try it with these two connected to each other, the two inside wires of the ext reg connector.

 

[GAU8A]

So, I am digging this thread up before I start wiring my internally-regulated three-wire alternator...

Sounds like I use the same red connection, and jumper the inside and outside wires of the alternator regulator connector? Does this eliminate the need to jumper between the battery post and terminal 2?

Thanks!

 

[Everett#2390]

Yes.

 

[Nyntyproof]

I used this wiring diagram today to convert my 69 Camaro to internal regulator. Works like a champ, 14 volts at the bus bar on the horn relay.
THANK YOU

http://www.chevelles.com/techref/tr14b.gif

 

[BPOS]

Old thread I know...

...but here is a foolproof solution to the wiring for a 10si or 12si

Alternator Conversion Kit We Make Wiring THAT Easy!

The short harness is a plug and play adapter for the 2 wire plug on the alt

Unplug the harness connector from the external regulator and plug it into the rectangular deal and tuck it out of the way. This does the proper jumpering of the wires.