VinMichael

I have a 1964 F-85 with a externally regulated alternator. I'm interested in converting it to internally regulated. Anyone done this?

jag1886

I would like to know this also to get a few more amps, did it years ago on a Chevy but don't remember how.

VinMichael

I'm wondering if it's the same thing as the Chevy..maybe with different color wires? I have no idea.
I found this regarding the conversion on a Chevy:
http://67-72chevytrucks.com/vboard/s...d.php?t=119379

oldcutlass

This works

11971four4two

american auto wire sells conversion plug in kits
best of luck. I called them on the phone to get my wiring issues fixed.
http://www.americanautowire.com/

joe_padavano

Whatever you do, do NOT use a one-wire alternator. You can get either a 12SI or CS130 style alternator that will bolt to your existing brackets. This thread shows two, one at 94 amps and one at 105 amps.

VinMichael

I picked up a 94 amp SI12 from the wrecking yard and it tested OK. I didn't get a CS130 from a 3800 motor because the bolt holes were further apart than the SI12 and didn't think it would fit.

Can anyone shed more light on prong 3 of the external regulator on the diagram posted? It is tied into the junction block. Do I leave it connected to the junction block? If so, the alternator will be getting two hot wires, right? (the other hot wire is coming from the horn relay).

Is the + Red power wire to the dash for the idiot light?

therobski

Here are some images of my set up on the 64. I had M@H Electric build a wiring harness for a alternator-built in regulator, HEI, no-wire for heater fan, tranny kick-down etc. I don't know if you can modify your existing harness for this application, Joe may know. Without checking my receipt, I'm almost certain my alternator is a 105 amp. I have my original harness if you need it.

VinMichael

Nice car. Your alternator is on the opposite side of mine. The alternator looks similar to the one that I bought - two prongs coming from it. As far as I know my harness is decent thank you for the offer.

therobski

I moved it over with brackets from a later 70"s A/C car, I installed a new Old Air Products A/C system on the passenger side. Glad I could help.

MDchanic

The diagram that Eric posted is pretty clear:
#2 goes to the red wire, which goes to the terminal block,
#1 goes to the brown wire, which goes to the ALT light.

- Eric

VinMichael

Do you know what the story is behind the "(+) Red power wire to the dash"? As of now, I have nothing hooked up to the prongs on the horn relay - been that way since I bought it.

MDchanic

The big red wire goes to the terminal block, and then to the battery, to charge the battery and provide power for the car.

The small red #2 wire needs to be a completely separate wire and also go to the terminal block. It is the voltage sensor for the regulator, and tells the regulator what the voltage is at the terminal block, which is the regulated point in the charging system.
It has to be a separate wire, so that the voltage that is sensed is not made artificially low by the amount of current flowing through the charging wire, and encountering resistance.

I'm not sure what kind of story you're looking for regarding the red wire to the dashboard, especially since there is no red power wire to the dashboard.
The red wire goes from the terminal block through the firewall to a splice, where it connects to other red wires that go to the headlight switch, the ignition switch, the always-on accessories, through the fuse block, the cigarette lighter, and one wire goes back through the firewall to the alternator and the regulator.

If I were you , I would run a 16ga wire from the #2 terminal to the terminal block on the horn relay, which is a different arrangement than the factory had when they were using an external regulator.

- Eric

cjsdad

Keep in mind that once the alternator is upgraded the factory charging wire becomes the limiting factor. The factory charging wire is terribly undersized and will not carry more than 30~40 amps continuously. You need to upgrade to at least 8 gauge to handle 90 amps or more. I can't seem to post the actual spreadsheet so the file below shows the amount of current a standard AWG wire will carry for a specific length.

Wire Gauge.xlsx

VinMichael

Lol nvm

VinMichael

I didn't know the gauge depends on length and vice versa - that's a logical way of thinking. I looked up another article that recommends 8 gauge for the charging wire. Thank you for sharing!

http://www.hotrod.com/how-to/engine/...rs-alternators

VinMichael

I think that I've got this figured out. For one, it turns out that my idiot light doesn't work so I ran my own wires from #1 on the alternator (the ground side) to the ignition switch (positive side) the opposite sides of a light bulb. This way the light turns on when the ignition switch at "ON" as it should. Though I've yet to test if the light goes off when running as it should.

To test the idiot light you ground out the brown wire (#4 wire of the old external regulator) with the ignition switch at "ON"

VinMichael

I got the car started and the idiot light does not go off when the car is running. It is really dim when it idles and get's really bright when I rev the engine. At the horn relay, it's at 18v when the car is at idle, but the battery is at 12.3v at idle.

Any ideas what is causing this?

MDchanic

Okay, I've been staying out of this, because in my book, considering the "unusual" way in which the factory wired the '64s, a number of wires need to be re-routed to have the circuit be "right" for an internally regulated alternator, and, frankly, I'm just not in the mood to go through that step-by-step.

I need to know exactly what you have connected to each alternator terminal, and what is going on with all of the other wires (regulator, battery, horn relay, etc.).

I'm not sure what you did with the ALT light. It sounds like you wired in a completely new bulb.
I don't know why you would have done that, so I guess I need to know what was wrong before that caused you to do that, as well.

Basically, I'm completely stumped, and have no idea what is going on, but I can say with confidence that there should be no circumstance under which a properly functioning internally regulated alternator should put out 18V.

- Eric

VinMichael

Thanks a lot for your help!. Your reasoning and also studying some other diagrams online was enough for me to figure it out so far without a step by step.

So far:
I have an 8 gauge wire going from the alternator power post to the horn relay. I have #1 on the alt going to a light bulb and then to the ignition switch. I have #2 on the alt going to the junction block.

I don't think the stock idiot light works anymore because the copper that runs on the circuit board for the light is lifting and cracking in quite a few places - though I'd need to pull the dash out to verify its affecting the idiot light circuit.

I think the horn relay is not working and isn't letting current pass through and that's why the reading is so high. Electricity is just building up with nowhere to go. It needs to pass through to the terminal post and then subsquently to the battery which I think isn't happening.

cjsdad

If you are not getting a connection from the alternator to the battery that could explain the high voltage out of the alternator. However, the alternator and the battery should be connected to the same terminal at the horn relay. The alternator should not be trying to charge through the relay.

VinMichael

Yes, I don't feel like the voltage is making it to the battery. I have the battery, and #2 sense wire going to the terminal lug. I heard it mentioned that the sense wire and alt power wire should be separate so the sense wire could get a reading of the batteries voltage; so the alt knows how much voltage to put-out; hence, the reason for running the the alt power wire to the horn relay.

However, the Caddy that I pulled the alt from had the sense wire looped straight back onto the alternator power lug.

BILL DEMMER

it sounds like that caddy was cobbled-disregard how the caddy was wired. the wiring diagram posted by oldcutlass is sort of the way to go. i skip the jumpering around of the original wires, it just creates more possible failure points. splice a 10si/12si connector on to the red and brown existing voltage regulator wires, matching color-for-color, and run them directly to the internally regulated alternator. as also mentioned above, upgrade your output terminal wiring(do not forget an appropriately-sized fusible link in that wiring). never, ever disconnect the output wire while the engine is running-it's the best way to fry the alternator, and the worst way to test(i don't care who disagrees with me on that, they're dead wrong). the horn relay/junction block is just that-a horn relay(nothing to do with the charging system) and a junction block(just a metal post to make wiring connections to, regardless of the relay). my thoughts on your excessive charging voltage: you have a bad connection in the sense line circuit, or, there is a problem with the 12si you got from the junkyard.


bill

joe_padavano

Huh? "Unusual"? I guess I'd better go look at the VC. I did this swap on my 62 years ago, replacing the generator, regulator, and melted wires with a 12SI (later a CS130). I just ran new wires since the old ones were toast. No issues whatsoever.

Yeah, that's just the lazy man's way of doing it. I will (sheepishly) admit that's how I wired my 62, since I was in a hurry.

Still works fine.

Have you verified that the alternator is working properly? Most auto parts stores can throw it on a tester for free.

MDchanic

Okay, I've simplified the '64 wiring schematic to illustrate what I would do if I were doing this job.

The '64 has a screwy setup where there are two main wires going into the firewall from opposite sides, and I would jump directly from the alternator output screw to the horn relay terminal post.

I would also keep the wire that originally went from the alternator to the main splice under the dashboard, and use it as my sensor wire, thus sensing the voltage at the actual main terminus of the wiring system. I have illustrated this setup, but there is nothing wrong with running a separate wire from the alternator #1 terminal to the horn relay instead.

You don't need the 10Ω resistance wire from the ACC terminal of the ignition switch to the firewall plug connector of the ALT light wire, but it shouldn't hurt anything to keep it either.

You need to be using a #168 bulb, or one of similar wattage - if the bulb draws too little, the alternator will not excite properly, if it draws too much... well, I'm not sure what would happen.

If you are doing the same basic thing that I am illustrating here, and you are getting 18V from the alternator, then the regulator inside the alternator is bad, and needs to be replaced.



Here is the schematic of the charging system as it was originally:




And here is the schematic of how I would hook it up:




- Eric

joe_padavano

Nice graphics.

The reality is that while your second schematic will work, none of those mods are necessary for a 12SI to function properly on a 64. All Olds did was run the sense wire directly to the BATT terminal, exactly how thousands of conversions have done it (and exactly how my 62 was wired). The reality is that all one needs to do is connect the large red wire to the BATT terminal on the 12SI, connect the purple sense wire to the #2 terminal, the light blue field wire to the #1 terminal, and install the jumpers in the old regulator plug as you have shown. If the alternator is functioning properly (not a given with a wrecking yard alternator) and the original car wiring is not screwed up, this simplified wiring will work just fine. If the original harness has been messed with, all bets are off.

MDchanic

Agreed, it would work without extra wiring, but leaving the old alternator BAT wire as the sense wire requires no extra work, so it actually saves a step.

Also, note that the original alternator BAT wire, and the original hot wire from the horn relay, are both 12ga, which, depending on the current that the new alternator actually puts out, may be inadequate. (I am ASSuming that newfangled high-current accessories, such as amplifiers, would be connected to the horn relay post, and not spliced in to the existing wiring under the dash).

- Eric

joe_padavano

Yup. This is the problem with most alternator conversions. People put in a new 100A alternator using the wiring sized for the old 37A alternator.

stellar

I just glanced over this thread, and it looks like there is an open circuit between the alt post and the battery. It would explain 18 volts at alt wire and 12 volts at battery. Cadillac came wired stock from the factory with the sense wire from the reg sense to the alt post using a short wire with an eyelet. I don't think it is as good, but that is the way they did it. You may try adding a temporary jumper wire from the alt post to the battery + terminal to see if the alt post wire is open. Leave all wires connected as is and add the jumper and then take a volt reading at the alt and battery. Things will even out a bit if the wire is open.

VinMichael

Thank you guys for sharing you knowledge, experiences, and anecdotes! I wired it as the Caddy was, and stuck the 8 gauge directly from the alternator power lug to the terminal lug; and looped the sense wire to the alternator power lug. I am getting 14v at the battery now at idle.

The idiot light is working as it should - off when running, and on with the key's at "ON". I need to check if I have a #168 bulb thanks for pointing that out, MD.


I did have the alternator tested on my way back from the wrecking yard and it tested OK.

VinMichael

I have another problem. I believe the alternator is drawing power when the key is off. When I disconnect the negative lead and measure with a multimeter from the negative battery post to the negative lead I am getting a reading of 12.4v. When I disconnect the sense and excite plug from the alternator the reading goes to 0v. I replaced the bridge rectifier, diode trio, regulator, and brushes and still have this problem. The original bridge rectifier had some bad diodes so that is why I ordered a rebuild kit.

I switched the multimeter to mA and it seems that I'm drawing 3.4mA.

Could there be something else causing the alternator to draw power besides the parts that I replaced?

stellar

3.4 milliamps is not a problem.

joe_padavano

I'm guessing you are using a low-impedance voltmeter. You need to use either a high-impedance meter or a test light. The low-impedance meter will read 12V even with a meaningless amperage. The high-impedance meter will filter these stray voltages out.

stellar

X2 It is probably actually 2 volts. A normal draw for an internal regulator of SI series.

lemoldsnut

So, I was reading another thread and this one was used as a reference. It is amazing how much knowledge many of you have. And appreciated as well.
I "upgraded" my 67 to have an external regulated alternator. To be honest not sure I needed to do that. But, I did. I used info from one of these threads to route the wires on the regulator plug and it works. Has for several years. However, when I put separate gauges on a few years ago I noticed that the alternator does not seem to charge until I bring the engine RPM's up to about 1500 and then it works even on lower RPM's except during long periods of idling like when in a parade or in line to get into a car show or something like that.

I have lots of external regulated alternators and regulators so going back would be about a 45 min change.

Any ideas on why? The only options my car has are being a convertible the power top, power windows, and it has a upgraded stereo to one of those autosound units which has no extra amp or anything.

Thoughts?

Larry

oldcutlass

I don't understand the question Larry, your car is already an externally regulated charging system. Are you saying you converted to an internally regulated, and then added a voltmeter?

MDchanic

Did you change to a "one-wire" alternator?

Where is your voltage sensor wire connected?

- Eric

Lee_A

For well thought out conversion "kits" along with some excellent electrical tech, check out Mark Hamilton's page:


http://www.madelectrical.com/catalog.shtml


I think it was back in the late 80's, when I bought my first kit from him. He has some "books" (self published, not a bunch of pages, but succinct and helpful) if you want to learn more about electrical systems in our cars.

lemoldsnut

I did swap it to an internal regulated alternator and not a one wire. Noticed the issue when I installed a volt meter.

MDchanic

What's your charging voltage?

Is your battery in good condition (does it hold a charge well? what's its resting voltage after the car hasn't run for a day?)?

Is the voltage to the Battery (-) terminal different from the output post on the alternator and from the terminal on the horn relay?

- Eric