Slow Battery Drain

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Cudakid2967

Cudakid2967

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So have a 67 Cuda into which we have put a brand new American auto wire kit into. Haven't had any problems so far, everything works(besides the horn which believe is in column wiring which wasn't replaced, just sticks every once in a while) but have developed a slow drain that just realized after finally leaving the battery connected for a while. Normally takes a couple of days of the car sitting to where it will drain the battery enough that all it will do will click the stater. We can't recall how old the battery is, the car sat for a year or so during a rebuild and we just put it back on a charger and stuck it back in. Where do I start to try to figure out where it is draining?
No radio, the heater isn't connected yet(haven't put the fuse in yet), no power seats, windows, etc, does have a tanks inc in tank electric fuel pump, and hei distributor. The battery has been moved to the rear of the car as well.
 
I'm not well versed in electrical but...take the charged battery to a parts store and ask them to do a load test. If that passes, check with a voltmeter(?) the draw on the battery when reinstalled in the car. Please chime in those that know how. Leave positive (?) cable disconnected and connect meter to terminal and clamp and see what it reads. Like I said, ask others before doing this, it may not be the correct way.
 
The first thing to do is fully charge the battery depending on what kind it is. Plain old lead acid can be charged with a 10 amp or a 2 map trickle charger. Then have it fully tested. Always charge and test the battery first.
 
You can disconnect the positive cable and check for draw between the post and clamp. A voltmeter will give you a reading that doesn't necessarily mean much. Same with a test light. 12-14volts will light a small bulb but it's the amps that tell you how bad the draw is. Most DVOM's (digital volt/ohm meter) will measure amps but are usually fused for 10 amps. If you tie into a unknown draw you may blow the internal fuse in the meter. Some of the old time mechanics use a headlight as a draw tester. If it's bright it is a pretty serious draw. If it just glows not a big draw. You can remove one fuse at a time to see which circuit is causing the issue.
 
Like Mike says, and don't forget to close the car doors, cause eventhough the interior dome light isn't illuminated, the voltage will flow, lighting your test light (or meter).
 
The suggestions above are good but one thing left out.

charge battery, yes
load test it yes
check for draw with test lamp and them ammeter yes
If you can't find it, LEAVE THE BATTERY with one post disconnected a couple of days and see if it goes down
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IF IT is a draw. Put a series device in the ground that will show the draw, whether a meter or test lamp

Start pulling fuses. Be sure to include the dome lamp as you'll have the door open. Do not forget the trunk or underhood lamp or the GLOVE BOX lamp
Cigarette lighters can "leak" when dirty/ corroded/ rusty.
If nothing shows up this way, disconnect the alternator and then re-check (Leaky diodes or leaky radio cap)
 
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