Battery keeps draining on 1950 Ford Custom

[Guest Aajord]

I have a 1950 Ford Custom with flathead v8 with the original 6v system. The key got left on once battery went dead tried charging battery finally went and bought a new battery. Put the new battery in and took the car for a drive got home parked it and went out later in the day to put it in the gargage and the new battery was dead. Does any one have any idea how it could drain that fast? And any ideas how to track it down and fix it?

[Guest Bob Call]

Obviously not the battery. There has to be a direct short in the electrical system somewhere. A bare wire touching ground? Voltage regulator points stuck? I'm not good with electrical systems. Someone can tell you how to use a test light to start troubleshooting. These inexpensive test lights can be purchased at parts stores or Home Depot or other hardware stores. Also can use an inexpensive multi-meter to test voltage, amperage draw, continuity, etc. Good luck.

[Dave Mellor NJ]

A good way to check for shorts is to charge the battery and disconnect the neg (ungrounded) cable. Wait till night, come out with a flashlight and touch the cable to the post. With everything off you will see a spark if there's a short (a ground is the same as a short) next get a drop light and find the fuse box. With the battery re-connected take out one fuse at a time then touch it back to the fuse clips looking for a spark. You should find the faulty circuit. Then trace the wire to the end looking for a pinch point or frayed insulation. Good luck and let us know if you find it.

[Dave Henderson]

Sometimes new 6 volt batteries sit on a store's shelf quite a while before selling.  Was there a test on the battery's charge level at the time of purchase?  I once bought a top brand 6 volter and discovered it was only about half charged when I got it home and checked it with a hydrometer.   Now,..do you know for a fact that your generator is charging properly?  If it isn't, it could be the cause of the first battery going dead.  Then, the new one, if sold to you with just a partial charge, could have been depleted enough by driving some that it wouldn't start the car.
 I would suspect stuck points in the voltage regulator, especially since the key had been left on before the first battery went dead, that could fuse them together and that would drain the battery quickly.  Most wiring shorts would have caused a blown fuse, and something like a stuck glove compartment light wouldn't pull the battery down very quickly.   And, "new" doesn't always mean a battery, if untested, is good.  Though not too likely, the replacement battery could be defective.  I'm a believer in having a hydrometer.  For about 8 bucks it is an ideal piece of test equipment to determine a battery's level of charge and whether a cell is bad, which dooms the battery.  Good luck, you'll find the cause.
 

[Guest Aajord]

Thanks guys, I'm just getting back to this problem, I'm going to send the weekend looking for bare wires and stuck points hope to find it, it's almost car weather 

Edited April 15, 2016 by Aajord (see edit history)

[Guest Aajord]

[Dandy Dave]

Agree with the Voltage regulator being the first place to look. Take off the cap and have a look. The other way you can go about it is to unhook the wire that feeds power to it. Also, un hook the ground side of the battery (Should be + ground on your old Ford.) and when you put the cable on it, if something is feeding all the time, (Like Dave Melllor NJ says) you will see sparks. A word of warning. If you just charged the battery, wave a piece of cardboard over it in a fan like fashion to dispel any Hydrogen gas that may be around it from the charging process. This is the stuff that made the Space Shuttle fly and it will explode in the right conditions. Not common, but I have had several batteries pop their top in the past. This way you can systematically go about disconnection different wires until you find the one that is draining the system. Remember while doing this, if the doors or trunk is left open, those dome or entry lights will be on and draining power. Also, as others have said, trunk, and glovebox light. Dandy Dave! 

Edited April 15, 2016 by Dandy Dave
Damn Spell Check! (see edit history)

[John348]

On 8/24/2015 at 11:27 PM, Dave Mellor NJ said:

A good way to check for shorts is to charge the battery and disconnect the neg (ungrounded) cable. Wait till night, come out with a flashlight and touch the cable to the post. With everything off you will see a spark if there's a short (a ground is the same as a short) next get a drop light and find the fuse box. With the battery re-connected take out one fuse at a time then touch it back to the fuse clips looking for a spark. You should find the faulty circuit. Then trace the wire to the end looking for a pinch point or frayed insulation. Good luck and let us know if you find it.

 

This a very good way to locate the drain. What I do to make it easier is I remove the ground (or return I thought ford use a positive grounding system, if that is the case remove the positive) Place the test lamp in series with the disconnected cable and the battery post, if the light comes on there is a load on the battery. This is the same as the arc that you would see at night. Remove circuits until light goes off.

Wires with frayed insulation would be a dead short and either burn clear or worse burn up, but it would not produce a slow drain, and when the battery is connected it would produce a rather BIG arc flash.

Could be a glove box light, trunk light that is causing the problem

[Marty Roth]

Above and beyond solivng your drain problem, consider adding a "Master Electrical Cutoff", so when you leave your car, eith at night, or at the local Cruise-In/Parking Lot, Motel while on tour, it prevents discharge, battery drain, and helps minimize the opportunity for theft.

 

Better to get a high-capacity switch for a shut-off, rather than the "quickie' type with a plastic wheel that attaches to the battery terminal, as they have less electrical resistance. The cheapies will sometimes decrease voltage/amperage to you starting circuits, but anything is better than nothing in most cases.