Electrical issues

[Coronet 14]

I'm trying to find a vampire draw on my 72 Coronet. It started with the AMP meter going from half to discharge to past charge to discharge. Replaced Voltage regulator. The guage now reads closer to the C on meter. I still have a vampire draw. battery will discharge if hooked up to car. I have gone through the car even disconected the fuse for clock still battery draw. Instrument fuse reads 5 volts when headlight switch is on and switch is turned to light up dashlights even with battery at 12 volts. I've taken battery to Walmart twice. The battery will only discharge on the car. When car is running Alt is running at 15 volts battery at 14 volts. When the car isn't running battery is 12 volts but will discharge to 2 to 4 volts. Is it possible that the Headlight switch is causing the low voltage at the fuse panel and causing the instrument panel lights to stay on even thought the lights are not lit up. Thanks

 

[Mopars & Missiles]

Just a hunch, but disconnect the HOT lead on the alternator and see if your current draw goes away? I've had a bad alternator that draws when the car is off, but will still charge close to normal when running. Shorted diode in the rectifier.

Its worth checking anyway.

 

[Hemi Rebel]

You need to measure current flow. Is your volt meter capable of reading amperage? Connect it at the battery and aee how much current flow there is. Start pulling fuses 1 at a time and see while watching amperage reading.

 

[Glenwood]

yep, sounds like the rectifiers in the alternator. Something is completing a circuit that isn't a dead short to ground; otherwise you might have fuses blowing, melting wiring etc. The ammeter connected to the battery should indicate how much current is flowing and will change when the offending component is disconnected.

 

[Coronet 14]

Thanks Guys will check that draw on wire on Alt tomorrow. I will disconnect it tomorrow to see if the battery still draws down

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Does it just backfeed through the hot wire when the car is not running and key is off Thanks

 

[Glenwood]

I got looking at schematics this morning and I think the alternator 'Batt' wire may connect to a lot of things. I'll scan and attach the schematic I have for a 1972 Plymouth which should be similar.
How long before the battery is drained to the levels mentioned? If it's a slow drain, the in dash ammeter might not tell you much compared to a digital meter.
Check solenoids, relays even ground connections. A stuck relay or solenoid won't draw power itself, but could permit current flow to whatever it's controlling.
Corroded ground connections can cause all kinds of weird stuff making it difficult to troubleshoot.

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[Coronet 14]

I disconnected the power wire to the ALT and left it off for a couple of days. Hooked it up and the battery maintained 12.5 volts for a couple of days. I turned the key on and off and it drew the battery voltage down to 11.2 volts. Key is off voltage is still dropping in battery. Will remove ALT tomorrow and take it to the electrical repair shop.

 

[Coronet 14]

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Heard from the electric repair shop today Rectifiers are bad A couple of other things were no good also. When I get It back I will try out my new tool.

 

[Coronet 14]

Got Alt back from the electrical shop. Seams to work good now. Drove it around the neighborhood needle stayed between the half line and charge. Tomorrow I will take it out for a longer ride. See if battery maintains charge over night. Thanks guys for the help on this.

 

[mopar 3 B]

What is the tool for? Over tightened belts are hard on bearings.

 

[Coronet 14]

When I would change the belts or have to tighten them up I didn't like prying on the fins. Trying to turn by the alt by hand while tightening the bolts was a pain. The tool just makes it easier.

 

[BudW]

Granted, you can overtighten the belt very easily with that tool - but I use one every time, myself.
It makes the job of working with fan belts, almost, a joy.

It is one of the best 10$ I’ve spent. My tool looks cruder than his, but will work exactly the same.

BudW

 

[rrTor-Red]

Granted, you can overtighten the belt very easily with that tool - but I use one every time, myself.
It makes the job of working with fan belts, almost, a joy.

It is one of the best 10$ I’ve spent. My tool looks cruder than his, but will work exactly the same.

BudW

Where can I pick one up? Does anyone know?

Thanks

 

[Coronet 14]

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