Easy swapping GM alternator?

tclark · 11-02-09, 06:16 PM

Anybody know of a GM alternator that is a direct(or close) replacement for the original? I don't mind a little modifying but would rather not have to anything drastic(no welder, torch, etc)I've searched but can't seem to find any info; surely there's one out there that swaps pretty easy. Mine is going out and I'd like some more juice without paying $400 for a Mean Green.

Elbert · 11-02-09, 08:36 PM

I've seen a few threads here that have dealt with minor modifications to get a GM alternator to work. Most involeved with shimming the bracket and installing a different pulley. Check out the FAQ area at the top of the general 60 section and the ever dreaded search tool.

I'm about to start looking into the correct wiring setup to adapt the CS130 ALt to the yota wiring harness or the next larger CS140 (I thnk those are the right model numbers for the GM alternators).

tclark · 11-03-09, 07:17 AM

Thanks, there's more stuff in the FAQ section that the last time I looked there. Need to check it out more often!

lehiguy · 11-04-09, 03:27 PM

The older GM alternators had a needle bearing in the rear if I recall. The newer ones are ball bearing front and rear. I have been running one with a self-exciting regulator for years. These are sometimes reffered to as a one-wire alternator as it does not need any source of electricity from the vehicle for the exciter coil. The later GMs required a 5-volt exciter coil source. There is no such thing on a Land Cruiser without using a series of resistors on a 12-volt line, which is what Land Cruisers use for the exciter coil. The one-wire solves all of that.

tclark · 11-04-09, 03:32 PM

Mind me asking what part # or model vehicle it came off of?

tclark · 11-04-09, 03:33 PM

Ah, nevermind, just noticed you were running a sbc.
I keep meaning to just take mine off and go find a match but just can't seem to get to it.

Elbert · 11-04-09, 07:02 PM

one wire alt is an aftermarket modification ... I too run a single wire GM alternator. I bought mine online but I would imagaine that an alternator shop can setup one for you. That would solve your wiring questions about the GM alt on a Yota vehicle. There are a couple of threads where guys installed GM alternators on their truck... probally used the old school alternator that came on mid-70s GM vehicles.

tclark · 11-04-09, 09:56 PM

I'm not really worried about the wiring, the one wire thing seems like a no brainer. I'm more concerned about mounting the thing up, pulleys, etc. From what I've read a lot of the GM stuff has the same diameter shaft as the stock one so that should be an easy swap.
Should I just take my factory one to a alternator shop and have it worked over? I really don't need anything crazy, but I'd like a little more than stock, and I'd like it to work well at low rpms. Don't even know where an alternator shop is come to think of it, reckon I'll have to find one and pay them a visit to see what they can do.

lehiguy · 11-04-09, 11:09 PM

Quote:

Originally Posted by tclark

I'm not really worried about the wiring, the one wire thing seems like a no brainer. I'm more concerned about mounting the thing up, pulleys, etc. From what I've read a lot of the GM stuff has the same diameter shaft as the stock one so that should be an easy swap.
Should I just take my factory one to a alternator shop and have it worked over? I really don't need anything crazy, but I'd like a little more than stock, and I'd like it to work well at low rpms. Don't even know where an alternator shop is come to think of it, reckon I'll have to find one and pay them a visit to see what they can do.

I bought the self-exciting regulator, a set of brushes and two new bearings and built one. It really is easy to do and these alternators are virtually lying at the sides of the highways, they are everywhere. Do not use Chinese bearings, they suck. I had one die in just a few months.

ntsqd · 11-05-09, 07:48 PM

I converted my externally regulated Mini to a Delco CS-130. There are only three wires total and two of them are nearly the same thing. The third is the excite wire that all non 1-wire alts need. I cut the pigtail off of an old regulator and plugged it into the truck's harness. Turned the key on and tested with a light to find the live one. Confirmed what I found with the FSM's diagram and made the adapter harness. Works great. I went with the std 3 wire version so that I can replace it with one from any parts store in BFE. Specific application alt that I used is for a '91 1/2t 4WD 5.7L Suburban (104A is the nominal rating).

The bracketry to put a CS-130 on a 22R is not trival. I hope putting one on a 2F-3FE is simpler.