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- - Alternator (https://67-72chevytrucks.com/vboard/showthread.php?t=820608)

Quote:

Originally Posted by Minkota (Post 8914754)

Since installing the new alternator, i am experiencing a pretty bad battery drain. is it possible that it is from the way it is wired?

I connected the 2 outside blue and brown wires at the regulator.
I connected the 2 wires at the alternator plug (previous owner made them them the same color wires black) and connected both of them to the White wire on the ne 12si plug. I feel this might have been wrong.
I ran a new 10ga wire to the battery from the the big red bolt on the back.
I ran a new 10ga ground wire from the alternator housing to the ground on the battery.

Don't just assume the drain is caused by the new alternator.. Using good troubleshooting techniques, track it down.. There are numerous threads and posts explaining how to do this and how to modify the wiring for converting from an external voltage regulator to an internal one, so I won't go over that again..

I installed a 12SI alternator a few months ago. Initially, I had the wires swapped at the alternator, and this created a battery drain. Here's how I have the wires connected now. The original voltage regulator had the following four wires connected to it:

brown
red
white
blue

I purchased a jumper that plugs into the harness in place of the voltage regulator, and it connects the following wires together:

brown to blue
red to white

The blue and white wires then run to the alternator and connect, as follows:

blue - 1
white - 2

Another way to say this is:

regulator brown connects to alternator pin 1 (uses blue wire)
regulator red connects to alternator pin 2 (uses white wire)

I went with a 100amp one wire alt. This made things simple.

Quote:

Originally Posted by LNP (Post 8914847)

I went with a 100amp one wire alt. This made things simple.

Where did you hook up the one wire?

Quote:

Originally Posted by MARKDTN (Post 8907187)

I would do a couple of things in your situation. I would get rid of the factory ammeter and go to a voltmeter. I would change to a CS144 (I would not use a CS130 as a paperweight). Delco #8077 pigtail is used if you have a lamp on the dash and the #8078 has a load resistor for use with no lamp to go from SI wiring to CS so you will have to do some adapting(different plug at alternator, but can use the same sense wires). Application for a 140A CS144 is '95 Buick Roadmaster. Then I would add a bigger wire from the alternator output to the battery. I might also add a junction block near the battery to power the fans and amp, that way you don't add any high loads to the original harness. While I was wiring, I would add headlight relays as well (to get brighter headlights and take load off the original switches and wiring).

If you don't want a CS144, then a 12si in either 78A or 94A. Anything bigger may have cooling issues. The 84-85 Corvettes do have a 12si that is 120A, but I would go CS144 if I wanted over 100A. 94A 12si is Delco 321-269 application '85 Riviera with 305Y, HD cooling and a/c. 78A 12si is Delco 321-244 application '85 Cutlass Supreme with 305Y. Nothing wrong with a 10si, I would just get a 12si if I was making the change since they have improvements. Don't use a 10si fan on a 12si, you have to get the 12si fan so be sure what you buy has the fan on it.

I agree, the CS130 is an overheating pile of junk that is a ticking timebomb of a roadside breakdown waiting to happen. The CS144 is a whole different animal and is a great design. I retrofit them into everything I can make them fit into. For 180-degree ears a 1996 Impala SS application is 140-amp and for serpentine accessory drives with 90-degree ears a 1999 Tahoe has a 140-amp CS144 as an option. If you can't make a CS144 fit then the 12SI is a great upgrade from the externally regulated stock part. A 1984 Z/28 with the HO 305 has a 180-degree ear 94-amp 12SI that fits great into classic muscle car brackets.

Quote:

Originally Posted by xs-cash (Post 8914856)

Where did you hook up the one wire?

The only wire I use is the battery wire from alt to battery. This setup will not
have a place to hook up a warning light. I have a volt gauge in my dash instead
of a amp gauge