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Battery Drain Problem

LurkinLimey

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Apologies if this topic hs been covered before, but think I have a battery drain problem and could do with some help as a newbie.
Took my '68 383 stroker Sport Satellite out for a 30 mile drive last week, and startup all OK as per usual.
Next morning totally dead electrics, no dome light, nada.
Changed out old battery (10 years old and looking a bit bulgy at the bottom) for brand spanking new and replaced all battery connectors with new as one was pretty broken up.
Car cranked and started better than ever before and took it for a short trip - alternator running fine.
Fri morning went to start up ready for first long run up to the Mopar Euro Nats at Santa Pod, and back to start of story with dead electrics, not even dome light.
So, suspect car has developed a battery drain - checked all no brainer stuff like no lights / switches left on.
Any idea how to start diagnosing / tracing this?
Can get access to a mutimeter, but though I'm mechanically pretty good am totally ignorant of all things electrical so could do with some pointers on how to proceed to get the old girl purring again.
Also, while at the show noticed that most other 68-70 B bodies (road Runners etc.) in stock configuration had a single Negative cable bolted directly to the engine block, while on mine it bolts to the intake manifold with a second smaller cable bolting to the radiator support.
Is this correct?
Any help appreciated,
Limey
 
OK, I will talk you through this and I'm sure others will add more info.
a. Your original battery was junk (typically only good for about 4 yrs) but you have another problem too.
b. 40+ yr old Mopars commonly have "some" electrical drain "somewhere" but usually not enough to drain a new battery overnight.
c. You are most likely not charging your battery while driving, even though you said "alternator is running fine".

Most likely causes, fixes & what to do:
1. To test your charging system "as a whole"...(all parts at once), put a multimeter directly on the battery posts with the car off. It should read right about 12.2 volts. Now start the car & repeat the battery test. It should read right about 14.5 volts. Use a multimeter for these tests.
a. not running - if less than 12 volts, your battery is low on power, so put a trickle charger on it (or have charged free at Autozone) & repeat the test.
b. running - if you have less than 14.5 volts, (such as same voltage running/not running of about 12 volts) then your charging system has a problem.

2. For a charging system problem (see 1b) do the following:
a. replace voltage regulator - you can run some tests to see if it's bad, but why? They're cheap, easy to replace & commonly go out, so I'd just replace it if it were me.
b. clean all the grounds on your negative battery cable connections. The negative going to your intake manifold & radiator support is "stock", so that's good, but those connections often collect rust under them, so scrape them to shiny metal. Clean the battery terminals too while you're at it.
c. Depending upon your year/alternator model, you will have either 1 or 2 "field wires" going to the alternator. These are the "small wires" that clip on. With the car running, make sure that one/both of those wires have right about 12 volts (multimeter).
d. Check the alternator "big wire" that connects with a small nut. There's a couple ways to test it, but I like to disconnect the positive battery cable (do this first), then disconnect the big wire on the alternator. Use your multimeter set on "resistance" (aka ohms - aka the upside down horseshoe symbol). Touch your meter wires (either +/- on either end) with one side at the loop on the "big wire" on the alternator & the other on the disconnected positive battery cable. The "ohms" should read pretty close to "zero"...maybe just a tiny number. Clean the big alternator wire loop while you're at it (sandpaper).

Report back what you find & we will lead you through this my Mopar brother!
 
yes negetive battery cable connected to the block and rad support is correct. Make sure all lights are off, doors closed, trunk closed and all elecricial item are off. If you have an aftermarket radio make sure the power to it is disconnected because it will draw power to keep the memory. Disconnect the negetive battery cable and connect a multimeter between the neg cable and neg battery post. Set multimeter to 10 amps DC and you shoud get a reading showing that you have a draw or you can just connect a test light between the neg cable and neg battery post (it will stay on if you have a drain on the batery), next start to remove fuses (one by one till you notice there is no draw on the multimeter or the light goes off) then you can check the circuit that you removed the fuse from and correct the problem in that circuit.
 
Moes makes a good point....some stuff (like dome light on all night) can drain a new battery.
 
Remove negative battery terminal. Take your volt meter and clamp one lead on the battery post and the other lead to the terminal end (battery cable end that you removed). Unless you have a clock in the dash it should be reading "0" volts. If you are showing voltage, start pulling fuses until the voltage drops to 0 volts. That will be the "zone" in which you need to investigate. Pull the interior light fuse first so you can leave the doors open. Check your meter with doors closed first before removing the fuse.
 
Since you do not have a multimeter I would lift the positive at the battery, if there is an arc you have something drawing power.
Pull 1 or more fuses at a time and lift the cable until off the battery until you don't have an arc. When no arc is present you know you have removed the fuse on the for hit that is drawing power...go from there.
Some of the old in dash ignition switches wear out and we think we have turned it to off but actually is in the accessory position when the key comes out...which can be easily identified with a test lite as half of your fuse block will be hot, or your radio will work...
I would invest in a cheap digital meter, maybe $20 @ AutoZone/Harbor Freight/Northern Tools.
 
After you find your short and since you say you are a newbie anyway, and this info is good for everybody else in Mopar land. Electrical Gremlins are one of the most common and frustrating problems that you will encounter on any Classic Mopar. So here is some info to read when you have time and file away in your saved folder or wherever you want to put it. Worth its weight in gold. DO the amp gauge conversion asap. Good luck
https://www.allpar.com/history/mopar/electrical.html
http://www.allpar.com/fix/alternator.html
http://www.madelectrical.com/electricaltech/amp-gauges.shtml
http://www.mymopar.com/downloads/1968/68BelvedereGTXSatelliteRoadRunneFull.pdf
 
IMG_1682.JPG
Not a fix, but I have found this multi socket for all my electronics to be helpful for output. Also not a fix, but I use the battery cut out marine grade from West Marine to ensure no parasitic draw overnight.
 
+1 on all the above. Go slow & think thru everything you’re doing. 1st thing is pull the dome fuse because you’re going to have the door/s open. Usually the 1st thing is dome light,trunk,hood, glovebox light staying on.
 
Make sure brake lights are not sticking on. Brake light switch may be hanging on all the time?
 
the bulging of the old battery suggests it may have been overcharging and could be killing the new battery. Can only speculate without running some tests using a meter.
 
Thanks for all the excellent advice all - Especially the comprehensive process from you PurpleBeeper!
Lots to think about and work through.
Will let you all know how I get on.....
All the Best, and Thanks again.
Limey
 
OK - Got myself a Multi Meter and findings as follows:
  • Battery Voltage after 24 hour bench recharge = 12.4v-12.6v
  • Battery Voltage after installing in car and posts connected = 12.33v
  • Battery Voltage with engine / alternator running at (usual lumpy) idle = 14.45v
  • Battery Voltage when engine cut = 13.04v and steady
Sooo - Based on guidance from PurpleBeeper I guess I don't have a charging issue, so next step is to start pulling fuses to localise the drain issue.
Also fitted a battery isolator / kill switch on the negative side so at least I have a fighting chance of using the car while I try and track down the drain issue.
Got a feeling in my water that it might be the dash wiper switch where the heavy chrome is peeling off and curling behind the switch.
Thanks once again for your patience and kind advice - couldn't have got this far without you!
Limey
 
Your charging system could be still failing when components are under certain load and/or heated up. It would help if you had a voltmeter gauge in the car while in use.
 
Now set your new multimeter to an ammeter setting, disconnect the negative battery cable, connect meter in series between the cable and battery post, or connect the ammeter across the battery switch connections, turn the switch off, measure the actual current draw with the vehicle shut down. Remove fuses one at a time to isolate the circuit drawing current. Caution, don’t try to start the car in this configuration, most multimeters can’t handle more than 10 amps of current.
 
Does the horn work? If it does not then it's possible the horn switch in the steering wheel is pulling in the horn relay constantly which will drain the battery, not sure it would do it overnight. But it is something to check.
 
Now set your new multimeter to an ammeter setting, disconnect the negative battery cable, connect meter in series between the cable and battery post, or connect the ammeter across the battery switch connections, turn the switch off, measure the actual current draw with the vehicle shut down. Remove fuses one at a time to isolate the circuit drawing current. Caution, don’t try to start the car in this configuration, most multimeters can’t handle more than 10 amps of current.

I'd have the multimeter set to voltage first to check for a draw. Have it set to the 20 volt position. Amperage setting might be too sensitive.
 
After you find your short and since you say you are a newbie anyway, and this info is good for everybody else in Mopar land. Electrical Gremlins are one of the most common and frustrating problems that you will encounter on any Classic Mopar. So here is some info to read when you have time and file away in your saved folder or wherever you want to put it. Worth its weight in gold. DO the amp gauge conversion asap. Good luck
https://www.allpar.com/history/mopar/electrical.html
http://www.allpar.com/fix/alternator.html
http://www.madelectrical.com/electricaltech/amp-gauges.shtml
http://www.mymopar.com/downloads/1968/68BelvedereGTXSatelliteRoadRunneFull.pdf
what's involved with chang over from amp to volts
 
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