Need electrical help (1 Viewer)

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If it is hooked up incorrectly it will always read wrong.

What does it do when the engine is not running, and you turn a load on... does it go positive or negative?

Is your alternator hooked up the correct way?
 
Its at 0 when the ignition is off. If I turn on the lights it will deflect to negative. I'm assuming the alternator is hooked up the right way. The B+ lug is connected to a white and blue wire, the plug is connected with wires into the F and E terminals.

I'm wondering if there is some wiring elsewhere in the cruiser that is not hooked up right. There is no wire going to the N terminal on the alternator. Is there supposed to be? It looks stock, though. I don't know...
 
Just checking out the schematics...

Your ammeter should have one side connected to battery + through a fuseable link & the other side should be connected to alternator output AND ignition switch & lighting circutis. This causes the ammeter to deflect to the + side IF more power is flowing through it FROM the alternator TO the battery (battery is low). If the system (Ignition switch etc) is drawing more power than the alternator can put out it draws off the battery and the ammeter deflects to the negative side, as power flows through it FROM the battery TO the system.

That confuse you more?
 
Yeah, I understand the concept (now), I just never thought about it before. Granted, until recently I never drove at night. It was mostly just short daytime trips. Once I got it built up more, I started driving at night. That's when I realized something was wrong.

So, back to my original question, what is drawing the power? Why will my alternator try to charge an already charged battery? And why will it not keep up with the headlights? Am I right to AssUme that there is a grounding problem somewhere?

You guys have given me lots to check so far and I really appreciate it. Unfortunately, nothing has worked. So, any other ideas?

Thanks!
 
It sounds like the voltage regulator is on its way out.... Here in Australia it is of the fire wall on the passengers side. If you get the wrong one it will not charge properly, as there are two available. The voltage at the battery when running at 2200 rpm should be around 14.4volts, if it is only 13, it is working as hard as a dole bludging bum. When you unplug the regulator, the alternator should charge at about 17 volts, tested at the back of the alt.
 
Somethin ain't right... Where did pinhead go?

Perhaps there is something tied to your ignition that has a partial short to ground, and is drawing aproximately 15A. When your ignition is off, there is no draw.

What does your meter read with the ignition on, but without the engine running?

Do you have ANY accessories attached to the + post of your battery? If you do, whenever they are turned on they would cause the ammeter to deflect to the + side, as it would appear to the ammeter that the battery is being charged when it is actually just powering loads through the battery... As you run more loads off the alternator side of the ammeter, more power is drawn off the battery, which would cause the reading to drop closer to 0 (i.e. headlights on) Then you add more loads and the meter goes into the - side more... did I just confuse you or myself?

If you are reading 0 with ignition off we know that there is no load on the system with the ignition off. If it drops to -15 with the ignition on but engine not running then there is a 15A load on your system all the time the ignition is on, so your alternator would always be putting out 15A.
 
So, why is my ammeter always deflecting to positive when no load is on the battery? Likewise, why is it deflecting to negative when I do put a load on the battery. .

I wasn't sure what you meant by reading + 15A after starting it, but if it never drops to zero amps, then it indicates 2 possibilities:

1) the battery is bad and never fully accepts a charge.
2) Somebody installed an electrical circuit on the battery side of the amp meter. In the stock wiring the battery is the only thing on the + side of the amp meter, so that it only reads current in and out of the battery.

It deflects negative current when you turn the lights on because either the alternator isn't putting our power ( which is why I asked you to test it in the truck) or it is wired incorrectly directly to the battery or wrong side of the amp meter.
 
Okay, here goes:

What does your meter read with the ignition on, but without the engine running?

It deflects just to the negative without the engine running and the ignition turned on.

Do you have ANY accessories attached to the + post of your battery?

Not on the battery itself, but as Pin Head pointed out, there could be something attached on the battery side of the ammeter. A long time ago (20 + years ago, long before it was mine) there was a radio and a CB installed in this rig. Maybe they were attached on the battery side. Or, maybe when they took these out, they screwed something up. I'll go through the wiring and find where they attached them.

I wasn't sure what you meant by reading + 15A after starting it, but if it never drops to zero amps, then it indicates 2 possibilities:

1) the battery is bad and never fully accepts a charge.
2) Somebody installed an electrical circuit on the battery side of the amp meter. In the stock wiring the battery is the only thing on the + side of the amp meter, so that it only reads current in and out of the battery.

1. The battery was bad, so I installed a new one a few days ago. I think Mr MoMo hit it when he said that it would burn up a battery if it was always charging. That battery was only about a year old. But, after putting in a new battery it still does the same thing.

2. As I said above, there used to be a radio and a cb in this rig. They could have been installed on the + side of the ammeter. If so, when they were taken out, they could have messed something up. Thanks for bringing it up, because it was somthing that I had forgotten about. I'll definitely look into it.

It deflects negative current when you turn the lights on because either the alternator isn't putting our power ( which is why I asked you to test it in the truck) or it is wired incorrectly directly to the battery or wrong side of the amp meter.

The alternator is new, so it should be working. I should have listened to you before. But, it was a 35 year old alternator, and for $50 I got a new one. The wiring looks stock going to the alternator. However, as I said before, there is no wire going to the N terminal. Is there supposed to be? The ammeter is hooked up properly since with the engine off, if I turn on the lights, the ammeter deflects to negative.

I'll look into the old radio and cb wiring and see if there is something causing problems. Thanks again for the suggestions.
 
1. The battery was bad, so I installed a new one a few days ago. I think Mr MoMo hit it when he said that it would burn up a battery if it was always charging. That battery was only about a year old. But, after putting in a new battery it still does the same thing.

2. As I said above, there used to be a radio and a cb in this rig. They could have been installed on the + side of the ammeter. .


1. Is the white wire with black stripe attached to the E (ground) terminal of the anternator connected to the base of the voltage regulator? If not and the VR has a bad ground it could cause over charging.


2. A radio or CB isn't going to draw 15 A, so (1) above seems more likely.
 
Yes, the white and black wire is attached to the VR from the E terminal.
 
SUCCESS!!!

Thanks everybody for all your help! Here's the story. I went to have the charging system tested today. The guy hooks up the machine and says that my volts are fine, but I'm only putting out 5-10 amps. He scratches his head and says, hmmm. I told him I have a new alternator, VR and battery. He said if the volts were high, he would figure it would be the regulator, but it was only the amps that were low. At about that time, the volts shot up to between 16 and 17. He suggested a new regulator.

So I went to Napa to get a new aftermarket regulator (again). Mind you, the old one was only about 2 weeks old. I got another points style regulator and slapped it on. The ammeter did the same thing it was doing before. I took it back to where I had it tested and it did the same thing. The guy still said it was probably the regulator. I said how can that be? But, I remembered a thread on here from bsevans having trouble with VRs. I decided to try a solid stated regulator.

Back to Napa, and then cross referenced VRs. Unfortunately, I have the old school style of voltage regulator where the wires screw onto a plate on the VR. All SS VRs are the plug style. I ordered one for a 73-76(?). I also bought some quality waterproof connectors. I got home and cut off all the ends and put on the connectors. I had to drill out the mounting holes slightly to get it to line up to the stock holes on my 71. Put it all together and went for a test drive. It worked!!

So, all told, I had a bad battery and 3 bad voltage regulators causing my problems. 2 of the VRs were new from Napa. It took the solid state VR to finally fix my problem. I am now done with point style regulators.

On the bright side, at least now I know my electrical system much better. I also know that all my connections are clean.

Once again, a HUGE thanks for everyones help. Mud rocks!! Now, I'm going to have a frosty cold beverage to celebrate. :cheers:
 

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