How do I switch to 1 wire alternator?

[BirdsThaWord]

I'm looking to go this route on my '68 Bird. My question is, what gets scrapped? I know there is an existing , external voltage regulator. Is it the silver box on the rad support, drivers side? Also, there looks to be a little resistor (?) beneath it. Can that go too? I dont want to start taking all the sheathing off for tracing the wires down if you guys expertise can make short work of it for me. Second question, where does the one wire go? Straight to the battery?

[rrunner68]

Nevermind, its a firebird.

[H2Ogbodies]

The 1-wire alts by design ar not a good choice. Stick with a 3 wire like a CS144 or CS130 and just convert to an internally regulated system. If I remember right, from the harness side of the regulator plug-in you have now, the yellow and orange leads get capped seperately while the blue and brown get spliced together. Then, you need to run a CS style alternator connector and splice your existing wires to it. I'm sure somebody has a wiring layout for it-I don't have one on file here on my laptop. You may need to install a diode if you are running a warning light-otherwise not. Curious though, what is the clocking on your alt. now? Are you running Poncho power underhood?

[67 455 Bird ragtop]

M&H fabrications sell a nice conversion kit that works with your stock harness. Very easy to install and not a lot of $$, around $20. Check them out at www.wiringharness.com

[BirdsThaWord]

The 1-wire alts by design ar not a good choice. Stick with a 3 wire like a CS144 or CS130 and just convert to an internally regulated system. If I remember right, from the harness side of the regulator plug-in you have now, the yellow and orange leads get capped seperately while the blue and brown get spliced together. Then, you need to run a CS style alternator connector and splice your existing wires to it. I'm sure somebody has a wiring layout for it-I don't have one on file here on my laptop. You may need to install a diode if you are running a warning light-otherwise not. Curious though, what is the clocking on your alt. now? Are you running Poncho power underhood?
Why do you say the 1 wires are not a good choice? What is a CS style alternator? If they are three wire, I'd still would not be cleaning up (reducing) the amount of wiring. If I run a diod for the "GEN" light, where would it go and where would I purchase it? Not even sure of what or where to buy one. What do you mean by "what is the clocking on your alt. now?". Yes, it is Poncho, a 350. Thanks and sorry for so many questions. I'm rather dumb about this stuff!

[BirdsThaWord]

M&H fabrications sell a nice conversion kit that works with your stock harness. Very easy to install and not a lot of $$, around $20. Check them out at www.wiringharness.com (http://www.wiringharness.com)
Thanks! I just looked at that. Appears to be the easiest route to take. Only concern is if the "Gen" light will still work. They didn't mention that. I guess a phone call to them is in order! Thanks again!

[AtomicFirebird]

I'm looking to go this route on my '68 Bird. My question is, what gets scrapped? I know there is an existing , external voltage regulator. Is it the silver box on the rad support, drivers side? Also, there looks to be a little resistor (?) beneath it. Can that go too? I dont want to start taking all the sheathing off for tracing the wires down if you guys expertise can make short work of it for me. Second question, where does the one wire go? Straight to the battery?

To answer your question, you have to be a little more clear.. If you are using a SI alternator you can keep the regulator and resister. If you are going to a one wire system with a CS style alternator, yes you can remove the regulator and resistor. An one wire alternator will work fine as long as you pick the right alternator. As for the Diode, unless you are running LEDs lights inside the car, you should be fine. From my understanding most new alternators have a diode inside. The CS is the last generation of alternators, sorta speak. There is SI and CS style. It all comes down to output and RPMs. Todays cars require more power and because of overdrive the old SI can't keep up with the demand like the new CS style. The CS style was created to replace the SI for the above reason. The CS style has a one wire that shows the Alternator or Gen light inside the car, you just got to know how to wire it. I have a CS style one wire alternator that lights up an LED inside the car and yes the LED has a diode. I ran my alternator wire to my starter just like the pick. I have an EFI distributor not a coil and distributor. This should help with the new wire connector you are going to buy..

[AtomicFirebird]

This is what I have, in CS style . The box with that all the wires going to it, represents the starter.

[6'9"Witha69]

Why = http://madelectrical.com/electrical-tech.shtml

What = http://madelectrical.com/catalog.shtml

[BirdsThaWord]

Atomic: Where are you getting those diagrams from?
6'9: Thanks for the links. Someone else ended up sending me to MAD's site before. Very informative and I'm saving that to my favorites this time!!!

Excellent! Thanks so much guys. I think this is something I can accomplish now. Also, here's a response that I've copied and pasted from another forum. The guy said he got this info from PowerMaster:
How do I hook up a one wire alternator?

Simply run a charge wire from the battery terminal on the alternator to the positive terminal on the battery. The onw-wire regulator is a self-exciting regulator, meaning that it has sensing ciruitry for alternator rotation. As the alternator starts to spin, this circuitry connects the internal voltage regulator to the battery and turns the alternator on. When the alternator comes to a complete stop, this same circuitry turns the alternator off.

When to use a one wire alternator?

Powermaster early style Delco alternators will work either way - as a one wire or OEM style. The main difference between a one wire and an OEM is the method used to energize or turn on the alternator. An alternator using the OEM style is turned on with the ignition switch. The one wire design is energized with a special sensing cicuit built into the internal voltage regulator. This circuit senses the rotation of the alternators rotor. The rotor must turn at sufficient speed to trip the circuit, starting the charging process. This turn-on speed is affected by several things and is typically higher with certain high amperage alternators. Once this circuit is tripped, the alternator will charge at all speeds, even very low ones, until the alternators rotor comes to a complete stop. At that point, the circuit will shut off and wait for the process to be repeated. What this means for the consumer is that in some applications the engine must be revved to 1200 or 1400 RPMs to turn the one wire alternator on. If the wiring harness is available and this characteristic is annoying, then Powermaster alternators can be plugged in like the stock unit and operated with the ignition switch.

I noticed that my Powermaster one wire alternator has to be "revved up" to get the alternator to come on. Why?

A one wire alternator has a turn on point (sometimes called cut in, which is typically 1200 engine RPMs). This is the speed where the internal sense circuitry connects the battery to the voltage regulator, thereby turning the alternator on. Once the voltage regulator turns on, the alternator will remain on and charging until the engine comes to a complete stop. If the engine idle speed and pulley ratio combination do not allow the alternator to come up to this point during starting, the engine will have to be revved up to turn the one wire alternator on. The sense circuitry in the one-wire regulator can be bypassed to excite the alternator as soon as the ignition switch is turned on. This is called three-wire operation. This means the alternator will not be dependent on reaching a certain turn on RPM.

<A name=3>Will aftermarket underdrive pulleys (power pulleys) affect the output of the alternator?

YES, especially when using a one-wire alternator. Changing the pulley ratio of the alternator by slowing it down will generally keep the one wire regulator from cutting on. This may also produce a low voltage problem at engine idle speed, depending on the amount of reduction. Powermaster alternators are tested with a 3:1 pulley ratio in mind. This is the recommended street pulley ratio, and the ratio used in most OE applications.

How do I hookup a one wire alternator if my stock alternator was an externally regulated alternator? What do I do with the regulator and wiring harness?

The only thing required to electronically hookup a one wire alternator is to run a charge wire from the battery terminal on the alternator to the positive terminal on the battery (or any positive battery source). The external regulator can be either totally removed from the firewall or left in place. If left in place, be sure to disconnect the wiring harness from the regulator. The wiring harness has to be disconnected from the regulator or the indicator light on the dash will remain on. NOTE: If the vehicle is equipped with an indicator light, the light will no longer be operative. Please see the following question.
My dash light does not work after I installed my one wire alternator. How do I get my dash light to work?

Some Powermaster alternators have an indicator light drive. The indicator light wire from the stock wiring harness has to be connected to this terminal of the one wire alternator. If the you had an OE externally regulated alternator, then use a conversion wiring harness (part # 150). If you had an internally regulated alternator with the two spade wiring harness connector, simply remove the black rubber cover on the side of the Powermaster alternator and plug the harness in. (PLEASE NOTE: This applies only to part #s 17294, 37294, etc. and not to part # 178021, etc.)

[H2Ogbodies]

Once tripped, does the voltage sensing circuit charge the system according to amp/voltage demand and vary constantly or is the amperage and/or voltage a fixed number? That is what you need to ask Powermaster. If they say no, then don't do it. Oem's don't use a 1-wire...must be a reason.

[BirdsThaWord]

Once tripped, does the voltage sensing circuit charge the system according to amp/voltage demand and vary constantly or is the amperage and/or voltage a fixed number? That is what you need to ask Powermaster. If they say no, then don't do it. Oem's don't use a 1-wire...must be a reason.
If no, what would go wrong? Again, I'm a dummy and am just asking so as to learn. If damage would occur, why would they be selling it that way?

[fordsbyjay]

Once tripped, does the voltage sensing circuit charge the system according to amp/voltage demand and vary constantly or is the amperage and/or voltage a fixed number? That is what you need to ask Powermaster. If they say no, then don't do it. Oem's don't use a 1-wire...must be a reason.

Once the alternator turns on it puts out 14.5 volts. The current level it puts out should increase with RPM just like any other alternator. I thought they used to have a graph in their ads but I couldn't find it on their website.

One thing to note is you CAN wire up their 1 wire alt to turn via the ignition switch like a regular alternator. Some models will run on 1 wire or 2/3 wire configuration.


How can I hook my one-wire alternator up as a three-wire alternator?

Some Powermaster one wire alternators (i.e., pn/n's 17127, 17294, 37294, 47294, 8002, 58005) can be hooked up as a three wire ...IF the vehicle is equipped with the two spade GM or aftermarket wiring harness. The Powermaster one-wire alternators have a black plug cover on the side of the alternator. This can be removed and the GM or aftermarket two-spade wiring harness can be plugged in for three-wire operation. See your alternator instruction sheet for further details.

[68Formula]

I converted to SI using the M&H kit. Plug and play.

http://www.wiringharness.com/PDFS/CAM_2010_Camaro.pdf

[speED]

Also interested in the 3 wire alternator. Local auto parts store does not understand what that really means. What should I actually ask for???

[Josh69]

I think the single most important difference between a 1 one and 3 wire alternator, that is often ignored, is that the 1 wire is primarily a battery charger. If you want your system to regulate itself and maintain 14.7v at the primary power junction, it needs to be regulated at that junction. A one wire alternator does a fine job of keeping the battery charged, and essentially functioning where it's supposed to...but it can't adjust to higher or lower loads, because it can't sense the change. You may only be seeing 13.8 volts at your power distribution (buss bar or distribution block, etc.) and that means you're headlights will be dimmer, your stereo output may suffer, etc. For an AM radio that is never used and now power accessories, you may never realize the difference.....and that accounts for about 98% of hot rodders. The one wire deal was mainly sought after to sanitize the install, clean up some wiring. Sure it works, but not ideally.

I'm running one wire now, works fine. I'm switching to 3-wire since I need a new alternator to keep up with my upgrades, A/C, wipers, stereo, etc. So I'll likely end up with a CS144.

[6'9"Witha69]

Also interested in the 3 wire alternator. Local auto parts store does not understand what that really means. What should I actually ask for???
Check the madelectrical.com links, in the 3 wire guide, it says what type of car to reference for eiher 10SI, 12SI, CS130, etc. If you don't see it there, call Mark. Just be ready to try callingseveral times, but when you reach him have a minute cause he LOVES to talk and is very knowledgable.

[MonzaRacer]

I do not even install CSI alternators as a one wire. On a CSI alternator wire the L terminal through your idiot light, the F terminal through a 10 am p fuse to a key on battery source, and I recommend looping the S terminal over to the Battery post as this take some load off the internal shunt for it.
also as with any car I recommend upgrading the charge wire to 8ga and remember t ocrimp, solder and shrink tube all connections.
Ihave a diagram if you need one for CSI type alternators. The older SI style alts only need the R terminal looped to the battery post and the F terminal ran to the idiot light.

[XLexusTech]

I have a nice chrome 1 wire alt if your interested