1955 Complete battery drain after 2 days (1 Viewer)

[dnhodge1]

Something seems to be draining my 6v battery down completely if I leave it for a couple of days without starting it up. Where would I start checking to see where this drain is coming form.

 

[MJB1]

do you have an original working electric clock still?
It may be that .
I have a battery disconnect in mine which stops any draining but of course you need to reset the clock.

 

[biddle]

Hey guys, something seems to be draining my battery down completely if
I leave it for a couple of days without starting it up. Where would I start checking to see where this drain is coming form.

When you post to the forum, your subject should be a summary of what your post is about which is battery drain. Your subject "1955 still on the old six volt system" has been revised to summarize what your post is about.

 

[Hilde]

Something seems to be draining my 6v battery down completely if I leave it for a couple of days without starting it up. Where would I start checking to see where this drain is coming form.

It's probably the clock. I had the same problem, so I put a disconnect switch on the battery, and I turn it off when I'm not driving the car. It works fine. After 2 weeks of being off, I still had 6.7 volts on the battery. The only problem is that I have to reset the clock when I turn it back on.

 

[74 Harley]

Sounds like a good sized drain, charge your battery and disconnect the positive,put a volt meter in between and read the drain. Now pull fuses one at a time and recheck. If you get through all the fuses with no luck check the voltage regulator or any non stock wiring.

 

[Hilde]

Sounds like a good sized drain, charge your battery and disconnect the positive,put a volt meter in between and read the drain. Now pull fuses one at a time and recheck. If you get through all the fuses with no luck check the voltage regulator or any non stock wiring.

The only problem with that is that a lot of stuff isn't fused. For example, the clock. It's on a 20-amp circuit breaker attached to the lighting switch.

 

[Ward 57]

I have seen this kind of thing before. I would suspect the voltage regulator. A stuck point in the regulator could be back feeding into the generator trying to turn it into an electric motor.
There are few other circuits that would pull that kind of current, the clock doesn't pull that much current and thousands keep their clock running for weeks with no issue. I had a P/U with A/C that the relay froze and kept the clutch engaged 24-7.

 

[1rmisner]

Something seems to be draining my 6v battery down completely if I leave it for a couple of days without starting it up. Where would I start checking to see where this drain is coming form.

could be the voltage regulator points are sticking. I would relpace it first since its the easiest

 

[doug7740]

I have to agree with Ward 57, the clock does not draw that much amperage to completely discharge the battery after two days. I still have a 6 volt system in my Thunderbird so after rebuilding the clock (yes, I rebuilt it and it was not converted to quartz) I connected it to a 6 volt battery and monitored the amp draw and battery drain. After 5 days the battery was at 6.15 volts, and the amp draw from the clock was still only 40 milliamps. I never disconnect the battery on my Thunderbird. In fact when I was on vacation the car sat for 28 days with the battery connected, when I returned the engine cranked over normally.

doug7740
1955 Thunderbird Blue

 

[CSPIDY]

Batteries can also internally fail or short, charge the battery and leave it disconnected and recheck it the next day.

 

[odannyboy]

Something seems to be draining my 6v battery down completely if I leave it for a couple of days without starting it up. Where would I start checking to see where this drain is coming form.

Disconnect the negative terminal, take a test light and connect one side to the batteries negative terminal and the other to the negative cable. The light should come on. Go to the fuse block and pull the fuses till the light goes off. That will tell you which circuit is your drain.

 

[dmsfrr]

. . . Go to the fuse block and pull the fuses till the light goes off. That will tell you which circuit is your drain.

.
There is no fuse block in a '55/'57 T-Bird.
Disconnecting individual power wires at their source may be a workable solution?

 

[Ward 57]

Batteries can also internally fail or short, charge the battery and leave it disconnected and recheck it the next day.

Especially if they are old. The sulfates on the plates can come loose and short out internally. Batteries have been known to catch on fire when this happens.

 

[Pink T-Bird]

It's probably the clock. I had the same problem, so I put a disconnect switch on the battery, and I turn it off when I'm not driving the car. It works fine. After 2 weeks of being off, I still had 6.7 volts on the battery. The only problem is that I have to reset the clock when I turn it back on.

Hmmmmn, no, a clock, if working properly, would take a few weeks to drain the battery. Remember there was no assurance these cars would be run every day, or even every week when they were originally sold. There is something else going on like a light staying on, a bad voltage regulator, etc. Sometimes even just a bad battery that won't hold a charge. It happens.

There are several articles on YouTube and elsewhere on how to trace a voltage draw, but a battery disconnect is a good place to start. If you have an ammeter open the switch on the disconnect, hook up the ammeter around the disconnect so whatever power is being drawn can be measured. Start on a 2 amp or higher scale so you don't blow the circuit protection in the ammeter. For reference the courtesy light over the radio will draw about 1.5 amps on a 6V system or 0.7 amps on a 12V system. You would need a draw of similar size, I would expect, to drain a battery in less than 2 days.

 

[Pink T-Bird]

.
There is no fuse block in a '55/'57 T-Bird.
Disconnecting individual power wires at their source may be a workable solution?

Yes. Once a bad battery is ruled out, pull all the fuses in the individual leads. Verify the draw is gone. Then replace the fuses one at a time until the draw returns. When the draw returns, that is your problem circuit. On occasion, the draw does not go when all the fuses are out. In that case it becomes more complicated because you are looking for something like a bad ignitions switch, headlight switch, damaged wire between the source (usually the ignition switch) and the fuse holder, or voltage regulator. Something without a fuse. Although when I had a bad VR on a 12V car, the generator light was on (less than full intensity) with the engine off and the key out. I didn't need to pull any fuses or measure amperage to fix that power drain.

 

[Ward 57]

All these tests relate newer vehicles. I remember selling cars in the 70's and the phantom draws were all over. But these cars were built with simple circuits. Once the key was off almost every circuit was dead other than the lights and clock.
Battery tests are the first step and an amp draw at rest is right on. The only circuit that would draw a battery down that fast is a bad regulator feeding back to the generator.

 

[dmsfrr]

There are several circuits in '55/'57 Birds directly wired to battery power that do Not have fuses or circuit breakers.
Frayed or damaged insulation and exposed bolt terminals on circuit breakers can also cause problems.
I suggest starting at the Battery terminal of the starter solenoid and disconnect the large yellow wires one at a time to start narrowing things down. Then move to the wires on the Ignition and headlight switches.
It has surprised me a several times (not in a good way) so I leave a battery cable disconnected any time I walk away from my '55.