[peabody67gto]

HI - I keep having problems with my original alternator in my 67 GTO blowing diodes and finding a new External Voltage regulator that I am having a Single wire Alternator built from my old case with my numbers from 67 so it still looks original. It just will not have a plug on the back for the 2 wires (blue-F & Black)

I just want to know has anybody used this type of alt on their car? And Also I think I will lose my Batt light because I think it had to do with one of the 4 wires going to the voltage regulator. I still have the original Delco Remy mounted and plugged in but it is not doing anything because it has no power going to it.

I am picking up the Alt tomorrow and just thought I would see if anybody used one. I hope I do not get any Alt noise in my factory underdash 8 track because the noise condenser will not be inline anymore. Now I am thinking I made a mistake converting it to a internal voltage regulator.

Only time will tell.

THANKS for any comments

[lust4speed]

The following are instructions I typed up because I kept forgetting what wire went where. Most of the information was obtained from Mad Electric's site. Your alternator is different because of using the old case, but since no one else responded I thought this might point you in the right direction.

The old alternator that required an external regulator had terminals marked F and R. The newer internal regulated alternator uses terminals marked 1 and 2. The other physical difference between the two alternators is that the older alternator had terminals that looked like || while the newer units the terminals were placed -- to keep someone from plugging the harness in to the wrong alternator. The 10-gauge wire hooks right up, but you have to change things on the other two wires. The old R wire will work if you disconnect the harness from the old regulator and bridge terminals 2 and 4 at the regulator harness. This should allow your idiot light to function properly. The Old F terminal wire goes to F on the harness (position 1, and you jumper this terminal to #3 terminal to allow the alternator to sense voltage.

[J_JAMNIK]

I am also converting from an external to internal voltage regulator. Somewhere in the threads, someone said to jump the number 2 and 3 regulator wires together and the F and 4 wires together. Lucky for me I used in-line fuses and avoided burning the regulator or any wires up. Can somebody that knows for sure help direct me in the right direction. I am not worried about the car looking stock. Just functional and clutter free. Terminal 1 is unknown to where the wire should go. I have connected a switched positive wire to terminal 2 through the ignition and the battery charges. Now to the guage: it is a charge/discharge guage. What is the wire scheme for this from the viewpoint of the original external voltage regulator and alternator to the internally regulated alternator?

[lust4speed]

The old alternator that required an external regulator had terminals marked F and R. The newer internal regulated alternator uses terminals marked 1 and 2. The other physical difference between the two alternators is that the older alternator had terminals that looked like || while the newer units the terminals were placed -- to keep someone from plugging the harness in to the wrong alternator. The 10-gauge wire hooks right up, but you have to change things on the other two wires. The old R wire will work if you disconnect the harness from the old regulator and bridge terminals 2 and 4 at the regulator harness. This should allow your idiot light to function properly. The Old F terminal wire goes to F on the harness (position 1, and you jumper this terminal to #3 terminal to allow the alternator to sense voltage.

Make sure you disconnect the harness from the regulator -- or gut the regulator and make the connections inside the empty regulator box.

Problem with the amp gauges is they only go up to 50 amps or less and the new one-wire alternators are going to peg the needle and possibly smoke the internals.

[J_JAMNIK]

Frying the gauge is what I'm afraid of! Non-functional gauges irritate me though. I'm not sure but can the charge/discharge gauge be wired one post from positive battery and the other from alternator output? Someone told me that this type of gauge just shows a relation between the charging voltage and the battery voltage, but I can't verify this. I have a spare dash that doesnt require lying on my back with my neck crooked to test the gauge. Anyone have experience with these gauges?

[george kujanski]

j_jamnik...what car is that on?

George

[J_JAMNIK]

68 Bonneville wagon. All gauge options on dash: fuel, temp, alt, and oil pressure.

[george kujanski]

First of all, the big cars did not use a 4 terminal regulator and harness so your conversion is a bit different than that of a "A" body.

Your regulator should have two wires; one goes to the old alt "f" terminal and the second wire comes from the ignition switch.

If you use a replacement 1-wire alt, all you need to do is connect the large output cable to the new alt.

If you want better battery voltage sensing, you can get a Delco 10SI or 12SI 3-wire alternator. Connect the two old regulator wires together and connect the old alt "F" wire to the new alt terminal 1. Connect the new alt terminal 2 directly to the battery (+) for battery voltage sensing. You can get matching connector plugs at practically any auto store.

A further improvement is to get a 12 indicator light bulb assembly and wire it in series with the old wire that came from the ignition switch to the reg. This will be your idiot light that indicates when the alt is not charging (in most cases).

The old charge/discharge gauge should work ok...if it ever goes full scale due to the new alt, it shouldn't be too much more than the old alt.

The gauge displays battery drain into the electrical loads of the car (discharge) or the charge current into the battery (charge). Since the only time the charge current into the battery will max out the alt is when the battery is very low, that situation will be infrequent.

Don't connect large loads like fans and fuel pumps to the ignition circuit from the ignition switch because that current will go thru the gauge and cause it to read high. Use relays with the power contacts wired to the battery thru fuses and the relay coil can easily be connected to the ignition circuit because the relay coil is low current.

George

[J_JAMNIK]

I'm going to try this in the morning George. The F wire from the regulator is the only wire I havent connected yet. It originally went to the right side of the old alt plug(looking at rear of alt with plug retainer at top). The regulator (Delco) was a four wire with two resistors on the back. I replaced it years ago with a Borg Warner that was also a four wire. The regulator harness only used the F, 3, and 4 wires. The 4 wire grounded to a capacitor. Someone had definitely messed with the wiring and put spliced a power wire to the 4 wire. What should I do with the other wire that plugged into the left side of the plug of the old alt? It runs directly into the fuse block. Is it just a switched wire? I don't run any electronics on the car except for an MSD box(relay activated) and the power windows/seats. Voltage drop at the rear wagon window is excessive, so more relays are needed(with car running, voltage at rear motor is about 9.5-10.00 when batt voltage is 13.3-13.5).

[george kujanski]

Your old alt is probably like the attached pic. The wire plugged into the "R" terminal is not used with the 10SI/12SI. Just disconnect it; I have no idea why someone would wire this into your fuse block.

In any case follow the above instructions and your internally regulated alt will work correctly.

George

[stellar]

peabody, sounds as if no one has dealt with the 10dn one wire (early style) did you get my e-mail last month? I gave you my phone #. If you still need help call me. did you get the oe reg #? it can be matched with an aftermarket, swap covers. # should be stamped on reg base. If reg isn't cause of diode failures, one wire 10dn won't solve problem. I've had very good results with 10dn one wire.

[devauxmidwest]

Originally Posted by george kujanski

First of all, the big cars did not use a 4 terminal regulator and harness so your conversion is a bit different than that of a "A" body.

Your regulator should have two wires; one goes to the old alt "f" terminal and the second wire comes from the ignition switch.

If you use a replacement 1-wire alt, all you need to do is connect the large output cable to the new alt.

If you want better battery voltage sensing, you can get a Delco 10SI or 12SI 3-wire alternator. Connect the two old regulator wires together and connect the old alt "F" wire to the new alt terminal 1. Connect the new alt terminal 2 directly to the battery (+) for battery voltage sensing. You can get matching connector plugs at practically any auto store.

A further improvement is to get a 12 indicator light bulb assembly and wire it in series with the old wire that came from the ignition switch to the reg. This will be your idiot light that indicates when the alt is not charging (in most cases).

The old charge/discharge gauge should work ok...if it ever goes full scale due to the new alt, it shouldn't be too much more than the old alt.

The gauge displays battery drain into the electrical loads of the car (discharge) or the charge current into the battery (charge). Since the only time the charge current into the battery will max out the alt is when the battery is very low, that situation will be infrequent.

Don't connect large loads like fans and fuel pumps to the ignition circuit from the ignition switch because that current will go thru the gauge and cause it to read high. Use relays with the power contacts wired to the battery thru fuses and the relay coil can easily be connected to the ignition circuit because the relay coil is low current.

George

George,

I've got a 67 Grand Prix with a factory ammeter in the dash. I'd like to upgrade my system from an external voltage regulator to a 12SI 3 wire system. The current voltage regulator has two wires connected to it per the attached drawing.
Should the voltage sensing wire go from the new alternator #2 terminal to a connection between the ammeter and the battery or should the voltage sensing wire be connected to the junction block?
I'm planning on installing relays for the headlights. Should the new headlight voltage source come from a connection between the battery and the ammeter?

Thanks very much

Rick

[george kujanski]

First, the schematic you show is a simplified version of the actual, which I attached from the '67 manual. For a 12SI or 10SI, for that matter, remove both wires from the existing regulator and connect the two together. At the alt, connect the blue wire to terminal #1 on the back of the alt. Connect alt terminal #2 to the red wire at the horn relay, (preferable and a convenient spot), or to the alt output stud, (easier) for regulator voltage sensing.

IF you connect the headlite relays to the red wire of the horn relay, that should be a good spot to tie in, Use a fuse from that point to the relays.

On the full size cars, the ammeter used is not quite what the simplified schematic shows. That schematic shows battery current going thru the ammeter, which is not quite correct. On the service manual schematic, a shunt wire is used in the under hood harness which is then connected to the ammeter. Full battery current does not go directly thru the ammeter.

George

[george kujanski]

Made a mistake....wrong pix here is the proper one

[devauxmidwest]

Originally Posted by george kujanski

First, the schematic you show is a simplified version of the actual, which I attached from the '67 manual. For a 12SI or 10SI, for that matter, remove both wires from the existing regulator and connect the two together. At the alt, connect the blue wire to terminal #1 on the back of the alt. Connect alt terminal #2 to the red wire at the horn relay, (preferable and a convenient spot), or to the alt output stud, (easier) for regulator voltage sensing.

IF you connect the headlite relays to the red wire of the horn relay, that should be a good spot to tie in, Use a fuse from that point to the relays.

On the full size cars, the ammeter used is not quite what the simplified schematic shows. That schematic shows battery current going thru the ammeter, which is not quite correct. On the service manual schematic, a shunt wire is used in the under hood harness which is then connected to the ammeter. Full battery current does not go directly thru the ammeter.

George

Thanks very much. The drawing I had made the ammeter look like a single point of failure.

Rick

[johnta1]

Here's a page on converting external to internal alternator.

Alternator Conversion

On the 1 wire alternators, it would be easy to wire up.
(they probably have instructions with it)

I wired my dragster to a '1' wire using the regular internal alternators. (3 wire)

Basically the number '2' terminal is connected to the Positive cable or wire at alternator.
The other is the switch side.

[devauxmidwest]

Originally Posted by johnta1

Here's a page on converting external to internal alternator.

Alternator Conversion

On the 1 wire alternators, it would be easy to wire up.
(they probably have instructions with it)

I wired my dragster to a '1' wire using the regular internal alternators. (3 wire)

Basically the number '2' terminal is connected to the Positive cable or wire at alternator.
The other is the switch side.

I'm wanting to do the 3 wire set up. I want to make sure I put the R/#2 wire at the best sensing spot on the system.

[johnta1]

In the original wiring loom for 70 Firebirds, (probably all 2nd Gen Birds), the #2 wire connects to the wiring loom at a crimped joint with other 'hot' wires. About half way back on the valve cover. (8-9 inches from alternator).

At that joint it would be 'sensing' the load from the car.
(most of the load goes to that junction, except starter power)

[devauxmidwest]

Originally Posted by johnta1

In the original wiring loom for 70 Firebirds, (probably all 2nd Gen Birds), the #2 wire connects to the wiring loom at a crimped joint with other 'hot' wires. About half way back on the valve cover. (8-9 inches from alternator).

At that joint it would be 'sensing' the load from the car.
(most of the load goes to that junction, except starter power)

Thanks!

I'll try to locate the similar junction on the Grand Prix.

[devauxmidwest]

Finally getting back to my 67 Grand Prix. Getting engine rebuilt, and will change the factory alternator with a 12Si 3 wire alternator. The car has factory gauges that include an operating ammeter gauge.

I understand that the B body cars have a shunt that is part of the ammeter circuit. Can I maintain my ammeter gauge function with the 12Si 3 wire upgrade?

Thanks