Charging problem

In the past I had problems with my charging system. I've done a few posts on this problem and thought I had this problem solved until the other day. I put the gold plated battery terminals you get from the zone , a while back, and they seem to work fine . I drove somewhere Sunday and everything was fine until I started the car to leave , then all of a sudden I get a diagnostics signal. The car started fine and I made it home, but it did not seem to have any power, I guess I was running off the alternator. The next day I checked the battery cables and I noticed the allen set screws had come loose, so I figured this was the problem.

Anyway I decided to change out those terminals and go with post type terminals and adapters. I've got a dual post and side mounted type battery, so I decided to split up the cables. I took the starter cable and put it on the side with a post adapter, no problems, starts fine . I took the other two hot wires and put them on the top post. The other three ground cables , I put the big ground cable on the top post and the other two on the side post. I later put all three together on top after thinking that was the problem.

What the problem is that when I start the engine, the voltage is fine, around 14 or 13.8 until I rev the engine. If I hold the rpms at around 2000, the voltage drops to around 12 volts or less, then when I let up to idle, the battery light comes on temporarily and then the voltage goes back up to around 13.6. Something tells me I've got resistance somewhere. The only thing I've done different is solder some copper cable ends. I wonder if this could be the problem, I think the solder has silver in it. I don't have a crimper for the ends, that's why I soldered them. I've had this charging problem before and it ended up being the hot lead cable from the alternator to the battery. I over sized this wire which they said was okay to do. In the past I also over sized the smallest ground cable wire. There are three ground cable wires, the biggest is I think 2 ga. , then a 4 ga. then a smaller one which I change to a 4 ga., I wonder if I should have done this? Keep in mind I've gone through all the wiring and had the alternator rebuilt by some pros. Any thoughts, thanks.

If you have a voltage drop at the connection of the soldered wire to the terminal I think you would expect it to get warm, so do any of those connections get warm when the rpm is 2000 and the voltage drops to 12 volts or less?

I had a '71 estate wagon that did something similar. Changed the alternator. Did the same thing.

Touched the alternator pulley and about blistered my hand! The almost new belt was as tight as a fiddle string , but was slipping.New belt installed and all was well.

And it [belt] never squealed. Appeared to only slip at higher speed.

Ben

If you have a voltage drop at the connection of the soldered wire to the terminal I think you would expect it to get warm, so do any of those connections get warm when the rpm is 2000 and the voltage drops to 12 volts or less?

Now that you mentioned it, after warming up the car and revving the engine, I shut off the engine and checked the cables. They all were cold except the two ground cables on the side, that's why I switched them. I think I should do an ohm's test to see if I get any resistance, but I have tried this before on the previous problem with the hot lead and it showed no resistance, but the wire was still bad. Maybe it's the wrong solder. Thanks

I had a '71 estate wagon that did something similar. Changed the alternator. Did the same thing.

Touched the alternator pulley and about blistered my hand! The almost new belt was as tight as a fiddle string , but was slipping.New belt installed and all was well.

And it [belt] never squealed. Appeared to only slip at higher speed.

Ben

I'll check that belt out , it's a possibility.

Mike

Sounds like a voltage regulator issue. I have had issues with no AC Delco alternators. Now days I only use oem or high performance alternators. Currently I run a 250 amp at 14.5 volts from DB electric. Nice thing it did not cost much over a generic replacement.

I will usually rebuild my own alternators. , rockauto carries most of the oem parts to do our cars.

Sounds like a voltage regulator issue. I have had issues with no AC Delco alternators. Now days I only use oem or high performance alternators. Currently I run a 250 amp at 14.5 volts from DB electric. Nice thing it did not cost much over a generic replacement.

I will usually rebuild my own alternators. , rockauto carries most of the oem parts to do our cars.

This morning I started the engine and got the same results. While I was revving the engine I did hear a noise but I could not find out where it was coming from . I shut the engine down, the cables were cool to touch and the pulleys were all warm, I guess from the engine temperature. I fired the engine back up and let it warm up, then I noticed the voltage was starting to act normal, or what I think is normal, also the noise quit. The only thing I did different was last night, was that I sprayed some belt dressing on the fan belt, and the fact that the battery had been disconnected. I wonder if it was a combination of things , maybe a loose fan belt and the computer trying to relearn itself?

I took the car for a drive with the air conditioning on, the average voltage was between 13.3 to 13.6 , with a hot engine, it was near 100 degrees , the battery is new. Seemed to drive okay, it does not seem to have much pep, but from what I've heard these cars are a little under powered. The only time the voltage dropped was at stop lights, as the engine idled down it might drop to 12.1 but would pop back up to 13.3 or higher. Does this sound normal , I hope. Mike