Sudden battery drain

[Sebringcharlie]

Just got my 72 satellite back from the engine shop. Had rockers, rods, lifters changed. Drove it home Friday. About a block from home, the gas gauge went squirrelly, then pinned to full.
Drove it to get iced cream Saturday night. Gas gauge flopped around, seemed to normalize again. Went to start it tonight, battery dead. Interior light barely lit, so a small charge present, but not nearly enough. No lights were left on, and doors were all closed tight.
Could these two issues be related?
Charging the battery now to see if it drains again tomorrow. Battery maybe 4 months old, so it shouldn't be a battery issue.
Any suggestions on where else to look for issues? ~for the mechanically challenged?~ (want to avoid another trip to the shop, lost 4 weeks of driving already)

 

[Dibbons]

My 1972 Satellite Sebring Plus has a four month old battery and it has been going dead, too. Yesterday, my neighbor told me he noticed my instrument panel lights had been on all night. I disconnected the negative battery cable until I can investigate further. Probably not your problem, but I thought I would throw it out there. My fuel gauge was working alright until recently, now it reads empty all the time.

 

[aldal]

One thing you can do is disconnect the negative battery cable and connect a test light between the disconnected cable and the battery and if it lights up you have something drawing power. If it does light up then pull one fuse at a time until the test light goes out and you will have the circuit that is causing the problem. Hopefully you can determine that root cause from there....good luck.

 

[black64]

Might want to check if the body to engine ground is there or loose. If there was engine work it is possible the strap was not put back on or loose. what Aldal said is also a good ideal in trouble shooting as well.

 

[Shorthorse]

It's hard to imagine how these two issues are related if the gas gauge was the only visual indication of a malfunction you could see.
The gas gauge wire (dark blue) runs from the sending unit in the rear, through the rear harness to the printed circuit connector (pin 9, I think) of the dash. For that to work properly the gauge has to be grounded and the dash has to be grounded. None of that circuit extends into the engine area where the work was done. If your ammeter works, did it show charging? Check alternator connections on the output and field wires.
And like everyone else has said, always check for proper ground integrity.

 

[Sebringcharlie]

You guys are fantastic. Thank you for all the suggestions. Charged the battery last night, took it for a 20 minute drive. Parked it for the night. Made sure interior lights were off, nothing left on. Went to pull it out today to check for the ground wire and the negative terminal test, dead battery. I'll push it out I guess and start looking at things.
Short horse, thank you for the info on the gauge, it's plugged solidly into the sending unit, which is new as is the tank. I'll look for the printed circuit connector, and look for a ground.
Ammeter currently pins to the right, needs charge. Which seems right under the circumstances lol
Off to root around hubby's garage for the tools and test light...

 

[VTCoronet]

I had a similar problem with a good battery dieing and found the trunk light was not shutting off!

 

[Sebringcharlie]

Just looked, no trunk light at all. Thank you! Also, cannot find engine ground strap. O.o

 

[furyus]

When the voltage regulator goes bad, the car will take a charge, and show charge, but as soon as you shut it off, it won't restart. At least this is what my 64 would do. Not sure if this applies to the newer style regulator.
Just something to check.

 

[Sebringcharlie]

Can the regulator go at any time? Pretty sure I still have the receipt, it will be less than 6 months old. Almost everything under the hood is brand new. I just got the car from restoration in may, and it spent June 15-July 10 at the engine shop for repairs. How can I tell if it's shot?

 

[Lionized]

Ensure that both mounting post nuts are attached solidly to the back of your ammeter gauge. My battery continually went dead until another member noted the same thing happened to his Charger. When I restored my instrument cluster I used lock-tite on the mounting nuts to prevent this from recurring. Make sure you disconnect your battery before checking the tightness of these nuts!

 

[Shorthorse]

Sebringcharlie, you said, "Ammeter currently pins to the right, needs charge"

I'm curious about that statement. Are you saying the amp gauge is pegged to the right even when the ignition and all lights are off or when the car is running? Does the amp gauge have any movement at all?

 

[Sebringcharlie]

When everything is off, the ammeter is in the central position. When key is on, it's pegged to the right, where the gauge says "C+".
I charged the battery for several hours today, voltmeter on battery terminals said 12.2 in key off position. After I installed new engine to ground wire and turned it on, volts went up to 13. Even fully charged, ammeter pinned to right.
Looks like I may have separate issues going on, but I won't know for sure until I try it again tomorrow.

 

[Shorthorse]

Your onto something. I can't imagine how an ammeter could peg + with the ignition on without a power generating source but if the ammeter pegs to the + side with just the key on, something is wrong. If anything, it should go to the discharge side. I'd check with the key off, battery charged and turn on the lights. Then try it with the key on. The ammeter should go discharge. That just lets you know the ammeter has some correct functionality. I agree with Furyus, it's starting to look like a voltage regulator issue or even the alternator. The voltage regulator housing should have a good ground itself. That's done via the mounting screws. Most Mopar regulators have a thick coat of paint. You may need to scrape some off at the mounting holes.

 

[Sebringcharlie]

While I wasn't able to take the beast out today, I did start it up. I tested the resting voltage 11.8, and compared to yesterday 12.2. Turned lights on, no ammeter change. Put key in, turned it to acc, and ammeter didn't move. Started it up, and it went right away. Ammeter not pinned to C+, but is still not resting at centre. Fuel gauge locked at full, but it may very well be full! After running the car, the voltage was back to 12
All I did yesterday was to install the engine ground, and I actually cleaned out my cigarette lighter. I was using it for a little air compressor I run to top up my air shocks, and thought maybe it was making a constant connection.
When the rain stops, I'll take it out for a toot and see if anything else changes.

 

[Sebringcharlie]

Today's resting voltage before start up was 10.7. So clearly there is a small draw somewhere...

 

[Shorthorse]

Need to start eliminating things. A good place to start is the battery. I know it's new but they do go bad for various reasons. Do you have a battery tester? If not, disconnect the battery completely, charge it, measure the voltage, and check it again later.
That ammeter gauge going to positive when the key is "on" is an good visual indication that something is wrong. I just can't imagine what it is. Hopefully someone can chime in. Until then, one step at a time.

 

[fuely62]

Curious, did all this start after they did the engine work? They don't have a wire pinched under the valve cover or somewhere else from the work they did?

 

[Sebringcharlie]

Yes. Never had an issue prior to the work being done. I cannot find any pinched wires, valve covers all appear sealed, and no unplugged wires that I could find. I did replace voltage regulator just in case. I will know this afternoon if it was the regulator.

 

[gyxffyg]

I had a similar problem with a good battery dieing and found the trunk light was not shutting off!

Well all of a sudden last week, my battery started getting drained. At first I thought I may have left a light on, but it happened again so I started trouble shooting this morning. So I disconnected the negative battery cable and using a test light I could see the drain. I finally read the above and even though nothing had been done in the trunk I took the trunk lamp out and the drain on the batter stopped. The funny thing was that I was expecting to see a plunger switch on the trunk lid that would activate and deactivate the trunk lamp, and did not find any type of switch to turn the lamp off/on. It is like it was designed to stay on, but that can't be right. Does anyone know what switch controls the trunk lamp?
So anyway, thanks to this thread I may have found the drain on my battery but won't know for sure until I leave it hooked up over night and check it tomorrow.
Thanks
:VB toast: