MY v-8/manual tranny swap is coming along good. (started as a v-6 auto) I have all my accessorys bolted on, but I'm having truble with the alternators.

My alternator for the v-6 is a 3 wire. One big red one that goes to the battery, and one little clip in harness that has a fat red wire and a brownish wire. I DO NOT have the v-6 alternator anymore. I only have the v-8 alternator, which has 4 wires. The power wire to the battery, and the little harness has 3, one fat red one, one brownish, one whiteish.

I tried just hooking the red and brownish together, but this doesn't seem to be holding charge, however I've only ran the car for maybe 3 minutes tops. Anybody know If the way i have it wired will work?

 

If you wire it up like u had it and leave the white wire hangin or cut it, you should be fine

 

The rear lug stays the same, it goes directly to the battery. On the plug, the heavy red wire also ties directly to the batt and should have 12 volts even with the key off. The brown wire gets tied to 12 volts and is key operated and usually has some resistance in it for what they call "sense". If you leave that tied to the red wire the gen will always be turned on draining the battery. You may need a resistor in that line, what year is the engine or gen from. You may be going from a CS to an Si unit, more info helps.

 

It's just a carbed 350 I think the car I pulled the alternator from was an 86 w/ a 305 orignally. I did notice on the v-6 car that the battery red wire goes to a little black thing with other wires going to it. then it goes to the alternator. I was thinking maybe this was a regulator. SO I may be going from CS to SI. Could I just get a v-6 alternator for it? MY z28 has the right alternator, and it has a 350, Would one of those work? I'd like to use the one I have on it, but if I have to buy the right one that's fine.

 

The little black thing is either a tie point or a molded connection with wires with fuse link coming off for things like the fan or other electrical feeds for the car, that can stay the same. Or if it's down by the engine thats the starter solenoid and that still can stay the same. The plugs are different from the Si to the CS as I remember, however either unit will work. I doubt you have a gen that had an external regulator unless it's really old.

 

I checked today, and the little black thing is just a tie in area, I noticed it the other day, but i didn't pay any attention. I also finally took it for a drive. It has NO frontend stuff at all, so I just cruised down the road a few miles and came home. I let it run for agood 15 minutes or longer and the voltage seemed to be holding steady, maybe droping a little, but that'd be froma somewhat old battery starting the car 12 times in half an hour.

If the alternator is not charging how fast would the ignition system run the battery dead? Stock H.E.I.

 

Depends on a few things, if the battery is fully charged and you don't run the accessories possibly several hours or more. Measure the voltage across the battery terminals with it running, it should be 13.5-14.8 or so. If it's below 13 then the gen is probably not charging. It normal for the battery to read high after you shut down, then it will settle down to terminal voltage which ideally is 12.6 volts. If a battery sits for a while a good 16hr trickle charge should bring it back, in fact a good trickle once a month is good maintenance anyway. It's often neglected but I have had lead/acid batteries last in excess of 10 yrs by doing just that. 12.4 or lower indicates a battery in need of a charge. Don't depend on the gen to do that, it's not the same thing as a battery charger.

 

I don't have a voltmeter, except the stock one in the car, so I can't measure volts.

So will/should the way i have it wired work?

Fat red wire to battery, red plug in wire to other red plug in wire, brown plug in wire to other brown plug in wire, White wire hanging there.

 

Most likely it will. Does the voltmeter go above 13 volts with the car running, normally after a cold start the guage will sit between the 13 line and the red zone. If it does you should be OK. If the gen doesn't charge when you start it it will be below the 13 mark and it will go way down if you turn on the lights.