Educate me on Alternators

[n33k0]

Greetings, gentlemen.

I'd appreciate some help trying to figure out what alternator I need for my truck. I took the old alternator to the local autoparts store to test it and they confirmed it was dead. I figured I'd just get a replacement of the same alternator while at the store but we couldn't find any part number on the unit, just "Delphi Automotive Systems" on the side with the pulley. The guy behind the counter asked for the truck info to look up the part number I needed, but the alternator that came up in the results didn't look like the one I have now, it had a V belt pulley while my truck has a serpentine belt. It's a 350 SBC, not many accessories other than an aftermarket radio powering two small speakers behind the seat. The alternator has two connections: a plastic clip with 3 or 4 metal pins (but only one wire coming out of it) on the side, and one heavier gauge wire attached to a threaded rod on the back of the alternator. I'm not sure where the wires are going, tracing them would require pulling apart all the wire looms the previous owner used to organize the engine bay. I don't know much about alternators, and I'm a bit overwhelmed trying to pick the right one for my truck. I'd appreciate any help you guys can offer.

[LongBox]

It seems that your truck is not stock, and this makes it tough to help. I'd just find a GM alternator with the same electrical connections, and swap the pulleys.

[WarMonger]

Do you have any pics of it. Lots of us are visual guys. Send a pic and maybe someone can point you in the right direction

[n33k0]

Originally Posted by LongBox

It seems that your truck is not stock, and this makes it tough to help. I'd just find a GM alternator with the same electrical connections, and swap the pulleys.

It's definitely not stock, I was hoping that maybe this alternator was found on a newer truck so I could just tell the guy at the store to look up an alternator for a certain year or model GM truck and buy that.

Originally Posted by WarMonger

Do you have any pics of it. Lots of us are visual guys. Send a pic and maybe someone can point you in the right direction

I attached some pictures to my original post, did they not go through? Posting from my phone, is it different than posting pics from a computer?

[VetteVet]

Probably a CS 130, Just ask for a CS 144 and you'll be good to go. They are a better unit than the 130 but are plug and play.
It's a conversion, and if the PO didn't add a resistor in that brown wire then a new alternator won't last long. The stock alternator was a 12 DN with an external regulator and a V-belt pulley. The CS and newer alternators used the serpentine pulleys.
The pulleys are interchangeable. You should be able to google the part number for the 144, I think they came out in 1994 with the single brown wire plug.





If you need any more help, post in the electrical forum and I'll see it.

[JimmyFloyd]

Looks like a Vortec alternator from a 96-99 Chevy truck. Probably swapped the front brackets/accessories, or the motor was swapped at some point.:

http://www.partsgeek.com/gbproducts/...ad=47584901292

[boostedc10]

Plug is wrong for a CS alternator, CS alternator had the squared off 4 pin. The plug on that one looks the same as an LS alternator plug. If I had to be on where it came from I would say 99-04 s10 or blazer with a 4.3L.

[n33k0]

Thanks for the replies, guys. From the looks alone, it seems like the 96-99 and 99-04 alternators posted above resemble the one I have most, the squared plug from the cs130 and 144 looks a bit different. Either way, that's three solid starting points for comparing at the store. Is a 100 amp alt. enough for the truck?

[RichardJ]

The CS-130 has 1 internal and 1 external fan so that easily identifies it as a different animal. The CS-130D has 2 internal fans.
The CS-130 and CS-130D are very different.
The CS-130D looks much closer to the AD230 and larger AD244.

The CS-130D, which I believe is the one pictured above, has fewer holes on the rear plastic cover than the AD series.

[leftybass209]

Originally Posted by VetteVet

Probably a CS 130, Just ask for a CS 144 and you'll be good to go. They are a better unit than the 130 but are plug and play.
It's a conversion, and if the PO didn't add a resistor in that brown wire then a new alternator won't last long. The stock alternator was a 12 DN with an external regulator and a V-belt pulley. The CS and newer alternators used the serpentine pulleys.
The pulleys are interchangeable. You should be able to google the part number for the 144, I think they came out in 1994 with the single brown wire plug.

If you need any more help, post in the electrical forum and I'll see it.

VetteVet, while I smell what you're stepping in, I think for clarity it should be restated searching for a CS 130 or CS 144, or any alternator type, not to step on your toes.

OP, those numbers CS 130, CS 144, or other alternators like 10 SI 12 SI, are alternator design types. You can't go into a parts store and ask for a CS 144, as they won't understand what you're saying. They'll type CS 144 into the computer and return 0 results.

You have to do the legwork yourself, by finding the model number (as VetteVet suggested). Match up the model number to what you have, then take the model number to the parts store and verify.

[RichardJ]

CS130 and CS144




Check out this video for CS130D and AD244

https://youtu.be/rNI926urErE

[1969c10joe]

i cant help mentioning i am impressed with the information here on all the threads I finally found a use for this internet

[n33k0]

There's a lot more to alternators than I thought, still going through videos and articles learning all I can. In the mean while, I went back to the parts store and bought an alternator for a 2000 Chevy 1500 and it looked identical to mine, bolted up without any trouble, and I ran the truck for a little bit without any issues. I still need to hook a multimeter up to the battery to confirm that it is charging, I might find time for that in the coming days. As far as what alternator amperage my truck needed, I figured if 100 amps was enough for a 16 year old truck with modern accessories, it would be fine for my 44 year old truck with very modest accessories. We'll see.

Thanks again for all the information and suggestions.

[franken]

You're pretty much right on the current needs, but be careful with the output voltage. Early systems liked ~14.5V but that went up and up as vehicles used more Watts. The Voltmeter on my late model reads ~18V.
People look at current output ratings of alternators, but that's max output. A source only provides waht's needed, so actual output is lower. Liken this to water flow--if you don't use water, no flow.
Voltage is pressure, like water pressure. Even if you don't use the water, the pressure is always there.
Watch the battery Voltage...

[RichardJ]

>>Early systems liked ~14.5V but that went up and up as vehicles used more Watts. The Voltmeter on my late model reads ~18V.<<

Flawed conclusion. You have a bad voltage regulator or bad ground somewhere. If you're looking at a "late model" dash volt meter and seeing 18V, it could be a bad volt meter. Check voltage at battery before you cook it to death.

[YBNORML]

Do you have anyone local that rebuilds electrical components? I haven't bought a "new" alternator or starter, ever. Ive always just had the original parts rebuilt, it typically costs a fraction of the price of a store bought rebuilt and this way you know its the right one.