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Discussion Starter #1
I've had my car parked for quite a while, just recently got it back out put something back together so I could drive it around.

When I hooked up the battery, the voltage regulator "clicked" and the "generator" warning lamp came on? This happened when the key wasn't even in the ignition!!

Somehow I'm powering the circuit with the generator warning light even when the key is out of the ignition?? This circuit should be cold unless key is in run position.

I found if I unhook any of the wires from the alternator, the relay "un-clicks" and the generator light goes out.

I have a remote ford solenoid wired up...if that was bad could it be energizing the ignition circuit??

I'm baffled. I also noticed the voltage regulator apperas to have failed allowing 14+ volts. I replaces this just before I put the car away..??

Any ideas? Would a bad voltage regulator cause the "run" circuit to be energized even when the car is "off"?
 

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Does the radio work with the key off? Is there power to the coil with the key off? It could be back at the ignition switch or something else that is wrong.
 

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Discussion Starter #3
Good point....I didn't notice anything else on...no other warning lamps for sure...but I didn't try the radio...

I'd say no, this is the only circuit energized....but I'm not positive.

If it is only generator circuit...does that point to the voltage regulator? I can't quite see how that would energize without energizing the rest of the things that would light up when the ignition was in the "run" position.
 

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My only thoughts were the ignition switch is defective, but if it is only the altenator, then I'm lost too. the idiot light goes through the ignition switch, so I'm not sure why it is comming on.
 

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Discussion Starter #5
I just checked this morning. Only the generator idiot light comes on...nothing else, no radio, no other idiot lights.

Here is another piece of the puzzle. When I noticed that the voltage seemed to be getting too high (14 volts) I diconnected the main positive wire from the back of the alternator for the rest of the drive home (just relied on the battery) and the generator light DID NOT come on!! Normally if I unhooked the alternator when the car was running the generator light would come on.

So it is almost like something is backwards? The generator light comes on when the car is off...and doesn't come on when it should when the car is on?

All I've done to this car is take off the front body panels and put them back on. The only part of the electrical system that was involved was unplugging the headlights turn signals etc...so not sure what happened.

Repeat of Main symptom...when the battery is hooked up there is a loud click from the voltage regulator and the generator light is activated...unhook the battery the voltage regulator "un-clicks" light goes off. This all happens with no key in the car?

:confused:
 

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Discussion Starter #6
My only thoughts were the ignition switch is defective, but if it is only the altenator, then I'm lost too. the idiot light goes through the ignition switch, so I'm not sure why it is comming on.
So this leads me to think it must be getting powered "backwards" through the voltage regulator...and grounding throught the ignition?
 

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Sounds like you have the old mechanical coil and points voltage regulator and one of the contacts is stuck. I have seen that happen before. You can get an all electronic voltage regulator for not much money. I bet that takes care of your problem or if you feel lucky, pull the cover off the voltage regulator and see if any of the contact points are fused together. Disconnect the battery before pulling the cover off the regulator or just unplug the harness going to the regulator.
 

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Discussion Starter #8
Thanks Kaiser..

That makes sense, my only place of confusion is why does diconnecting the alternator fix the problem. Even with the alternator diconnected, the voltage regulator still has power from the battery, so if it was the voltage regulator causing the problem, wouldn't the problem sill exist even with the alternator diconnected?

This is making me think that somehow the alternator (original from 71) has a problem and is shorting the main power wire on the back of the alternator to those two blue and white wires on the back of the alternator causing some sort of short circuit in the voltage regulator. The blue and white wires coming off the back of the alternator also run to the voltage regulator. What do those other two wires do anyway?

Is there a way to test the voltage regulator?
 

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Nate,

The idiot light under normal circumstances has 12V on both sides of it. When one side drops, then it illuminates. You wrote that you recently replaced your regulator....with an old mechanical version:confused: Also, my solid state regulator puts out about 14.6V max which apparently is normal for these. Your ignition may be feeding the lamp similar to the MSD run-on problem.

Even with the alternator diconnected, the voltage regulator still has power from the battery, so if it was the voltage regulator causing the problem, wouldn't the problem sill exist even with the alternator diconnected?
Not necessarily, because it's not regulating anything. Your set-up should be similar to below. I'll try to upload a service bulletin for the regulator if I can get my scanner to work.

 

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Discussion Starter #10
Wow, thanks Jack, great knowledge.

I'm not sure about the mechanical vs solid state, I replaced the original 71 regulator with one that looks exactly like it. I'm sure I just asked the parts guy for a voltage regulator for a 71 Nova. It must be mechanical becuase something is definitly moving inside causing the "click".

Does the solid state regulator hook up the same? Is this a part number from a modern vehicle or...?
 

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Wow, thanks Jack, great knowledge.

I'm not sure about the mechanical vs solid state, I replaced the original 71 regulator with one that looks exactly like it. I'm sure I just asked the parts guy for a voltage regulator for a 71 Nova. It must be mechanical becuase something is definitly moving inside causing the "click".

Does the solid state regulator hook up the same? Is this a part number from a modern vehicle or...?
Another thing to keep in mind is that a fully charged battery has about 13.6 volts across it. So, you need a regulated voltage higher than that in order to charge. I think your safe up to around 15 volts.

The solid state regulator hooks up exactly the same. The standard Delco-Remy replacement is #1119515, which you should have no trouble finding. I believe there are other after-market versions which are cheaper, but why bother. I don't think anyone makes a a mechanical version anymore, it's just not worth the hassle.

Then again, you may want to consider switching to a modern system (CS or SI). The only reason I kept mine "old" is because I had a spare regulator and I was able to get a remanufactured Delcotron alternator for $37 which is something the Paddock or Classic Ind would want $100 for. You should get your alternator tested a couple times. If you want to troubleshoot the system, here you go (your symptom is on the 4th page):
http://s861.photobucket.com/albums/ab175/JackBurton_bucket/

 

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Sounds like the Alternator is bad. A bad rectifier bridge and or diode trio bad. Replace ALTERNATOR. I would check to see if you have bad grounds, from your front end cleaning. [run a ground wire from the reg ground bolt to the Alternator ground stud]
 

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Discussion Starter #13
thanks guys for the insight, hope to look this weekend.

I did have a chance to pop the top on my "new" voltage regulator I put on a couple summers ago...definitly the mechanical type.

I'm leaning towards alternator thought too...something bad allowing full battery voltage to just flow through the alternator as if the alternator is actuall producing the voltage. The alternator is on the same positive circuit as the battery pos terminal and the voltage regulator...Only when i hook up the alternator does the gen light come on when car is off.

I'll be sure to post what I come up with . Alternator is original from 71 but only has 64,000 miles on it.:eek:
 

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Discussion Starter #14
Ok now that I"m looking at Jack's diagrams more closely (my boss is going to kill me!) I'm really confused. It doesn't appear the the generator indicator lamp could EVER light up unless the key is in the ignition and at least turned to accessory.

My generator light comes on even when my key isn't in the ignition at all! How culd this be possible, without the ignition switch being closed, according to the diagram, the light is on an open ended circuit......:confused:
 

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Discussion Starter #15 (Edited)
According to jack's diagnostic book...

Ignition off - Lamp On - engine off = bad generator

Looks like Plowman might be right, off to the alternator testing station I go!

I still don't see how the indicator light can be illuminated with the key out of the ignition. Even with a bad diode in the alternator allowing the indicator light relay to energize, that would simply ground the indicator light, it wouldn't provide any positive voltage too it? According to the diagram, the positive voltage has to come through the ignition switch and with that open (no key)....I don't see how. But...I'm not an electrical engineer, so I'll follow the diagnostic and get the alternator tested.

(Sorry for all the posts, I like thinking 'out loud')
 

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Discussion Starter #16
It was the alternator. The test stand failed it right away, didn't even have to spin it up. The guys at the parts store were baffled, they said it was pretty rare failure. Of course it is from '71.
 

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If you have had parts off check all the ground wires for good conection a bad ground backfeed will do all kinds of crazy thingsThe voltage reg and battery both have body grounds
 

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I would lean towards a bad diode in the alternator. The diode is basically a one-way switch. If it is bad/blown it will back feed when the ignition is turned off.
 

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Sounds like the Alternator is bad. A bad rectifier bridge and or diode trio bad. Replace ALTERNATOR. I would check to see if you have bad grounds, from your front end cleaning. [run a ground wire from the reg ground bolt to the Alternator ground stud]
This is what i suspect!

Bad diodes!

The first thing that came to my mind as i read the heading.
 
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