Alernators: Anybody Know what size resistor required from teh 10/12 to c144 swap?

[broncoman6524]

I got all my pulleys today, along with my A/c delete bracket.

Next up is the alternator, Obviously I can't just swap pulleys from my V-belt alt to the new one. So I'm going to have to buy a new one.

My boss was telling me about how the newer model alternators are wired differently than the older Non computer alternators. Something about having to wire is a certain way to trick it, enabling it to function correctly. And me be able to run my carburator without problems.

Anybody have insight into this?

 

[dremu]

I got all my pulleys today, along with my A/c delete bracket.

Next up is the alternator, Obviously I can't just swap pulleys from my V-belt alt to the new one. So I'm going to have to buy a new one.

It's not obvious, or at least not to me. See below.

My boss was telling me about how the newer model alternators are wired differently than the older Non computer alternators. Something about having to wire is a certain way to trick it, enabling it to function correctly. And me be able to run my carburator without problems.

Anybody have insight into this?

Umm, donno how "new" is new ... but the 1990's-era Pontiac Transport alternator I got for my '74 (which is what, a CS130?) had the same number of wires as the old one. The plug was different, sure, but hell, the wires were the same color ... eight bucks worth of plugs from the parts house and a little soldering and heatshrink and it's wired up.

All the alternators I've ever seen require a voltage to excite them or whatever it's called, but it's not like they have tachometers in them or something crazy.

Also, I was able to take the serp pulley off it and replace it with the V-belt style, so I imagine you could make it work the other way. Motormite or somebody makes replacement pulleys, so a good counterman at a local non-chain parts house oughta be able to fix you up.

Now, it might be *easier* to get a newer-style alternator, but if you have a working one that's wired up and mounted to your motor, seems to me like it'd be easier to change the pulley.

-- A

 

[broncoman6524]

Hmm...I'm going to have to find a fact serp alt and find out. I could have sworn they look different, I could be blind though...

Clocked at a different angle of something?

The truck is an 84, and the Serp set-up came from an 90. I was wondering if they were wired the same? I can't remember, and I'm not smart enough to look at those things before I take it apart. ha

 

[broncoman6524]

Just walked outside and looked again, unless I'm stupid my stock alternator will not fit in my serp brackets.

Bolt holes are too spaced apart for one, plus it's too "fat"

The only other alternator that is a Serpentine style is on my sisters 97 tahoe, which has like 4 or 5 wires into the back. Definetely not 2 haha.

I'm going to stop at Autozone tomorrow and compare a bunch of different ones.

 

[onetonbb74]

go to the parts house and tell them you have a 1990 and need an alternator w/ a serp. setup. Id bring in the bracket just to be sure it fits.

 

[sweetk30]

you need a cs 130 to fit stock. and this will get you a 105 amp max off the self.

or get a optional 125 amp for a 96-up vortec 350 and its a cs144 bigger better alt and the 1 8mm bolt hole nere center of brackets needs to be sloted on the alt only and a longer bolt used.

and same plug for cs130 or cs144 alts.

i got a bigger alt for mine. replaced the wimpy cs130 105 amp with a built up cs144 at 200 amps .

search my screen name and cs130 or cs144.

good pics and info here. http://coloradok5.com/forums/showthread.php?t=236217&highlight=cs130

 

[broncoman6524]

Okay, so from my recent information overload from that post. And the posts inside that post.

I'm going to get a Cs144 alt, go the the J/y and steal the connector. then solder it plus resistors into my factory harness.

Then cut the mount on the Alt and be done.

What size resistors?

Missing anything?

 

[dremu]

Okay, so from my recent information overload from that post. And the posts inside that post.

I'm going to get a Cs144 alt, go the the J/y and steal the connector. then solder it plus resistors into my factory harness.

Then cut the mount on the Alt and be done.

What size resistors?

Missing anything?

My understanding is that the resistor replaces the dash indicator light.

Should you have have said light, you can wire it straight up. If not, assuming a 50mA load, a ~250ohm resistor, 1W or so, would work.

You can also get the connectors at the parts house if desired. (Not exorbitantly expensive and maybe easier than cutting an old one out.) I got a female one to mate to my existing harness and a new one to plug into my new alternator, so I built a little pigtail to drop it in. I can swap it in and out of either truck as required.

-- A

 

[dyeager535]

MY preference is to get a wrecking yard connector. I paid way too much (IMO) for a connector that didn't work right. $25 for a connector end and a resistor, which I still had to cut and solder to make work right.

 

[dremu]

MY preference is to get a wrecking yard connector. I paid way too much (IMO) for a connector that didn't work right. $25 for a connector end and a resistor, which I still had to cut and solder to make work right.

Mine were maybe $5 a pop?

-- A

 

[sweetk30]

i have a factory gauge in dash no light. i hooked mine no resistor works just fine. and junk yard 1 day and a wire cutter got my plug.

 

[dyeager535]

Yeah, I was dumbfounded at the cost too. To get started with I thought it was going to be something special. Now I know better. Then again, $25 is about the going rate for most connector pigtails anymore (CTS for the ECM for instance) so I shouldn't have been surprised. Usually I don't even consider new an option because of this.

The more I think about it, is the resistor what "tells" the alternator to shut off? I'm trying to understand how that would work, but since the "charge" bulb (if present) is only operational when there is a fault in the alternator OR when the vehicle is off with the key on, it sort of makes sense to me. The other two wires into the alternator are constant hot, leaving the resistor wire as the only one that can indicate whether the vehicle is on or off.

I guarantee the resistance is built into the circuit for a purpose solely regarding the alternator, or GM wouldn't have done it, and clearly state such in the manuals.

Stole this from http://oljeep.com/gw/alt/Alternator_Theory.html#Section_3


Removing CS-Series Alternators…
Always disconnect the Negative Battery Cable before doing anything
Disconnect the PLI/FS voltage regulator connector before disconnecting the BAT terminal
Disconnect the BAT terminal last
The alternator is now ready to be removed

Installing CS-Series Alternators… Always disconnect the Negative Battery Cable before doing anything!
Install and secure the alternator with the mounting hardware
Attach the BAT terminal before connecting the PLI/FS voltage regulator connector
Attach the PLI/FS voltage regulator connector
Insure belts are tensioned properly and there is no interference with the alternators terminals
Connect the Negative Battery Cable.

"L-Terminal: This terminal is connected to the “Low” side of the warning lamp, with the lamp’s “High” side being fed by the ignition circuit. Some regulators require a 35-ohm resistance inline with this circuit if no lamp is used otherwise alternator damage may ensue. Some applications have a resistor connected in parallel to the lamp in case the lamp bulb opens up and burns out. The resistor will be there to provide a path for current and voltage. Some vehicles supply a 5Vdc reference to this terminal from their ECU or Computer; other vehicles don’t, so be aware of the various models of regulators. Other regulators may be tested by application of a 50-Ohm pull-up resistor to connect the L-Terminal to the 12Vdc source, I believe that any resistance between 35 Ohms (5-Watt resistor) and 500 Ohms (1/2 Watt resistor) can be used safely."

"A RESISTOR is included, which is calibrated to protect voltage regulator electronics (the regulator is within in the alternator)." (http://www.madelectrical.com/catalog/cs-130.shtml)

Again, I'd like to see WHY they require a resistor.

 

[broncoman6524]

I do have a gauge, NO light.

So, I will be needing the resistor, and according to what dyeager posted a 35-ohm will work?

 

[dremu]

I do have a gauge, NO light.

So, I will be needing the resistor, and according to what dyeager posted a 35-ohm will work?

Takes over 300mA to make the alternator happy? Dayum. Have to be a 5W or higher at that low a resistance.

I'm still thinking a 250 ohm, 1W or better should do. Plus 35 ohms is a weird value, so unless you have an NTE dealer or a good TV repair place in town, it'll be hard to find. Heck, even Radio Shack doesn't carry so much in that stuff, though they do have a 10W 100 ohm that would prolly do:

http://www.radioshack.com/product/index.jsp?productId=2062293

-- A

 

[dyeager535]

The quoted text above says 1/2-5W, can you deduce from a 194 bulb what kind of resistance value it would have?

I'm out of my league when we start talking this stuff. Can you explain why the resistor is "required" when some are obviously running without them?

 

[dremu]

The quoted text above says 1/2-5W, can you deduce from a 194 bulb what kind of resistance value it would have?

I'm out of my league when we start talking this stuff. Can you explain why the resistor is "required" when some are obviously running without them?

The latter, no clue.

Your normal 194 apparently takes 250mA, which is more than I woulda figured.

That means it's about 50 ohms and consumes about 3W.

It's all ohms law, man ... V=IR, P=VI.

-- A

 

[dyeager535]

I did see that in some cases the regulator didn't need a resistor, but there are apparently multitudes of different regulators, so you may or may not have a problem without it apparently.

 

[broncoman6524]

Reason I said 35ohm was the post quote above from dyeager says that

Some regulators require a 35-ohm resistance inline with this circuit if no lamp is used otherwise alternator damage may ensue.

 

[dyeager535]

I'd run with what Dremu says. I've seen it said elsewhere that the resistance value isn't particularly important, and judging by the range given, 1.5-5W, to me seems that it's probably not critically important that you nail a specific value, as long as it's not above or below that range.

My thread shows the value I got with the range settings on the multimeter, just not sure how to deceipher it.

 

[dremu]

I'd run with what Dremu says. I've seen it said elsewhere that the resistance value isn't particularly important, and judging by the range given, 1.5-5W, to me seems that it's probably not critically important that you nail a specific value, as long as it's not above or below that range.

My thread shows the value I got with the range settings on the multimeter, just not sure how to deceipher it.

I would agree that the value isn't critical... but, umm, the wattage of the resistor isn't what determines its behavior in the circuit. The *resistance* (ohms) does that. The power rating (watts) just determines how much heat it can dissipate before the Magic Smoke comes out

-- A