I just bought this 83 Camaro and it had a problem in the charging system. The altenator has a two prong connector and a wire going from the alt to the battery. One of the wires from the connector goes to the alt output and the other was connected to the wrong wire and the alt. was not coming on. So I connected the wire to a brown wire that was (I assume) the correct one, because the alt. came on. So I drove the car around a little and it seemed to be working. When I turn on the lights and use the wipers and turn signals the voltage drops and the turn signals slow down to the point of blinking about once every 10 seconds. I just put in a new alt. from the parts store. I have an a/c delco battery and the eye is still green. So my question is what is going on? Is it the battery, the alt., or should I re-route where the voltage regulator reads the voltage from?

 

I also forgot to mention that right next to the post where the positive cable connects to the starter, there is another post that has a wire connected to it and the wire is hot, but it is not connected to anything! Where does this wire go?

 

Anyone!! PLEASE help!!

 

Please say that you disconnected the battery before you connected the brown wire to the harness.....

Once the car is running, the battery no longer has any say.... it just gets re-charged, while the alternator does all the work. Double check you're grounds, battery cables and terminals, and if the voltage drops that low when you put on an accessory, then you're alternator is definitely fried.

The brown wire leads to the Electric Choke Relay. The other wire you mentioned, is it Red, or Black/red? This wire to comes from the alternator, and connects to the starter...

In what way is it not connected, on which side (the alt, or the starter side)? Either way, if it's not connected, it's gotta be it.... cuz that'll cause voltage drop.

 

Yes I did disconnect the battery before I connected the brown wire. When I went to the parts store and told the guy at the counter I had an 83 camaro and I told him the original 305 had been swapped for a 350 from a pickup truck. He told me that the alt would be the same as for the original 305. Is he full of it? Should I bring back the alt? I just bought it about a week ago, so I wouldn't think it would be toast. The wire is red and it is connected at the starter right next to the post where the + cable is connected to the starter. It runs up twords the alt. Where on the alt. should it be connected, the voltage regulator or the output post? This is how it is now. + bat cable to starter and alt output, brown wire to volt reg, volt reg to output post, red wire from starter to ????

 

I re-edited my post above, take a look

The alternator should be fine, but if you drove around with it.... especially with that wire down by the starter disconnected, make sure that it's not blown or fried.

 

I edited mine too! Please help

 

The thicker red one (with the connector already IN the alternator), is on the outer side (passenger side).... with the thinner brown one on the inner side (towards driver side).

 

right now the brown wire is in the bottom and the thicker red is on the top and is connected on the other side to the output of the alt. Where does the thick red wire from the starter connect on the alt? the alt. output, or the thick wire in the two prong connector?

 

The output comes directly from the battery, but the wire you're talking about, that comes FROM THE STARTER, this connects to the alternator two prong connector....

After all this is finished, make sure you check you're fusible links down by the starter.... to make sure they didn't fry up (you'll know if they did, if the car suddenly won't turn over)....

 

So it should be wierd like this: from the alt. there should be one wire from the output to the battery. From the alt. plug one brown wire and one red wire connecting to the starter. And if the voltage still goes down when the lights go on, or flutters when I use the turn signals than the alt. is fried.

 

Also, does it matter that the alt. I got at the parts store was for the 305 that was originaly in the car. Not for the 350 pickup engine that is there now

 

The Brown wire does not go to the starter, it goes to the electric choke relay that is found underneath you're dashboard (it follows the harness, through the firewall).

Everything else is correct....

 

The alternator is fine, as the only difference is when you run TPI.... more amps is needed. But since you're running a Carb, you can drop in a 454, and that alternator will still do just fine.

 

So my new alt. is fried and I should return it then?

 

If all the wiring is hooked up, and you're grounds (including straps), cables and terminals are good. Have the alternator checked out by the store you bought it from..... and if it's bad (and you have the receipt), tell them that THEY must have had a bad batch.

Most auto parts stores (especially the biggies), almost always comply....

 

I've checked the terminals, but excuse my ignorance, what are straps?

 

You'll see a strap that's connected to the firewall, to the engine (on the left side of the distributor). It's a 'flexible' strap.... make sure it's secure, and bolted down good on both ends.

 

Ok thanks for your help, I really appreciate it! I'l check the straps and the wiring again. And come back here tomorrow and post my results. Thanks again for the help!

 

Well I returned the alt. and checked the grounds again. All look good, but the voltage stil goes up and down when the turn signal is on, and there is a noticeable drop when the lights are on. Wiring is correct. Any ideas on what could cause this?

 

If you are positive that the wiring is all hooked up right (grounds, etc...), and the alternator is good, you must have something else taking away from the alternator.

Do you have a test light? If you do, diconnect the positive cable on the battery, and position the test light in between (the side with the clamp, clamps to the terminal on the cable.... the side with the 'pointer', will be pressed down on the battery's post)....

If the light goes on, with the car OFF, then you current leakage. If this is the case, you'll have to, one by one, remove the fuses in the fuse box (one by one, so you don't forget where they go back), and each time you remove one, try the test light again. Once the light refuses to go back on, whichever fuse you pulled last will prolly be the culrpit....

If the light doesn't go on at all from the very start, it HAS to be somewhere in the charging system.

I know you said you had a good battery, but make sure it's good (that green light means little), cuz a bad battery will drain the alternator. That's why it's always a good idea to remove the battery with the car idling, then check the volt gauge....

 

It is NORMAL for the guage to swing with the turn signal, and it is NORMAL for the charging rate to drop with accessories on e.g., headlights, heater blower etc. Never unhook the battery while the car is ideling, it is a stupid way to test. The resultant voltage spike generated can cause all sorts of problems with the auto electronics. Yes, always start with a fully charged good battery when testing. Fact is that at idle alt output is low and most of the current to run things is off the battery. It is normal for a voltage drop to be seen under those conditions. If the guage swings up off idle above the 13 volt mark the charging system should be fine. If you have a voltmeter with the car running and accessories off at idle you should see about 13.5-14.5 volts on average. If you do the charging system is OK. I have a 140 amp alt and it pretty much acts the same way as the 105 did at idle with heavy accessory load. Sound to me like you are OK.

 

No arguement intended, I'd just like for you to delve deeper in what you were explaining....

To quote strand's first post, "When I turn on the lights and use the wipers and turn signals the voltage drops and the turn signals slow down to the point of blinking about once every 10 seconds". This doesn't sound normal to me.....

Why is this a 'stupid' way of testing for a bad alternator, through a possible draining battery? He's not running TPI, nor an ECM.... and people have been doing this for years, as a quick test (for those without the proper tools), having great results.....


To run what things? The battery merely charges during idle, unless the car is just in the 'key on' position, and not started.... then it could be used as a direct source. I've ran state to state with only an alternator (because of a bad battery, which was removed prior), and had no problem of any voltage drop....

I don't think he has a 105 amp, as the LG4's in 83 (I think) came with a much lower alternator....

 

in 83 it was a 63 Amp for No A/C and 78 Amp w/ A/C

 

I was responding to this post. You will see a drop anytime the turn signals or lights are turned on. 83 models used an ECM, unless I missed it somewhere in the posts. The brown wire is the "sense" wire. The plug will normally have a hot with ign on, usually a heavier wire than the other one. If you tie the brown or tan(sometimes hard to tell) directly to 12 volts either to the other wire in the plug or to the back lug you can wind up with a condition like you say. The alt sense wire usually has a resistor in series with it to provide a slight drop in voltage to the sense line. Reason is this, the alt only senses voltage so if you tie the sense to a direct 12 volt source it will not charge at full output. Usually they run the sense wire to a point inside at the point of max voltage drop so it will keep everything around 13 volts or so. Go to a Radio Shack and get a 1N5401 or similiar 3-5 amp rectifier at around 100 volts. It will have a band at one end, the band goes towards the alt plug. Hook the other end to where you now have the brown wire going. The diode will provide about a half volt or so drop to the sense wire and will bring up alt output. As far as running without a battery, no expert or alt manufacturer suggests doing this. I did it once on my old 65 Impala but on any modern vehicle I would not recommend it. As far as amps are concerned it's all relative. Fact is that with any charging system a good part of the time depending on load the battery supplies a lot of the current for lights etc.

 

Ok so let me make sure I'm clear, one end of the rectifier to the brown wire, and the other end to the wire going into the alt plug. Or are you saying to put the rectifier on the thicker red wire that goes into the alt. plug? Right now there is one thick red wire from alt. out put running to the battery. One thick red wire from alt. plug running to the starter. And one brown wire running from alt. plug to wiring harness.

 

The brown wire is the sense wire. If it is tied directly to 12 volts the alt will have low output. There is usually a resistor somewhere in the harness in the brown lead. If it is stock leave it alone, my assumption was that it was attached by you to 12 volts. I suggested a diode because it will give you a half volt or so drop to tell the alt to throttle up more. Leave the red wire alone, that is simply the main power in to the alt for the field. The sense wire controls how much charging output you get. Follow the brown wire a few inches from the alt and cut it, the band end of the diode goes to the plug end and the other end attaches to the end that goes to the harness. Then see if you get more output. You can use a resistor but the diode has heavy leads and you can put heat shrink right over it and leave it in line.

 

Yeah, that's right. So long as the car came equipped with the LG4 originally, the Brown wire from the alternator leads to the Electric Choke Relay through the harness, found under the dash...