Electrical drain, battery won't maintain charge?

Old Henry said:
Don't know if this would apply to your modified '36 but on my '47 I always get a little spark hooking up the battery because the electric self winding clock has unwound and the contacts are closed to energize the electro-magnet to rewind it. When I hook up the battery a split second connection that immediately opens shows as a spark. Could be as simple as that.

As others have said, you really need to check the magnitude of what you are thinking is a continuous drain with a meter. May be just something like the clock or a condenser charging that makes the spark but is not really draining. Even just a test light between the disconnected battery clamp and the post would show that without a meter. If it just flashes on then off - no drain. If it stays on bright - it's a definite drain.

If you're not sure about your battery, wouldn't hurt to have it checked. They do wear out.
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Professor, BTW enjoy your travel logs, hooking up test light from pos.post to pos. cable produces no light at all. I do have a quartz conversion clock, but this condition existed before I got the clock; I have an electronic ignition, no condenser.
 
Think I may have isolated the problem and owe an apology to those who suggested a diode as the culprit.............maybe. When I remove the fuse for the clock the positive cable no longer sparks when hooking up. Do quartz converted clocks have diodes in them? This clock was just done by Williamson's. Can I use my meter from fuse panel connection to the power lead from the clock; what setting do I set my meter on and what value should the readout be?
 
Am going through circuits one by one on the hot side fuse panel, my horn has a relay switch and when I activate that circuit for the first time the positive battery cable sparks the first time I make contact but when I immediately do it again the cable doesn't spark, is that a function of the relay switch?
 
36tudordeluxe said:
Professor, BTW enjoy your travel logs, hooking up test light from pos.post to pos. cable produces no light at all. I do have a quartz conversion clock, but this condition existed before I got the clock; I have an electronic ignition, no condenser.
Click to expand...

36tudordeluxe said:
Think I may have isolated the problem and owe an apology to those who suggested a diode as the culprit.............maybe. When I remove the fuse for the clock the positive cable no longer sparks when hooking up. Do quartz converted clocks have diodes in them? This clock was just done by Williamson's. Can I use my meter from fuse panel connection to the power lead from the clock; what setting do I set my meter on and what value should the readout be?
Click to expand...

If a test light won't light between the battery cable and post, you don't have a drain on the battery. The little spark caused by the clock isn't a sign of a drain enough to kill the battery. It would take years for a clock to kill a battery. Same for a relay solenoid.

I think it's time you check your battery with a battery test apparatus like they will hook up for you at NAPA or AutoZone, etc. I'm thinking that's your problem myself.
 
Going to take battery to AutoZone and see what they say.
This has been an ongoing problem for some time, I was able to live with it by manually tripping the circuit breaker after having driven the car each time; this way the battery wouldn't run down by the next time I drove it.
 
I learned the hard way that ALL electrical trouble shooting begins with the battery. I had a brand new battery with a shorted cell. An old timer had me try to start the car while he watched with the caps off the battery and one of the cells bubbled like it had an alka selter in it.
 
Here's my latest update: using test light from positive post on battery to disconnected positive battery cable. As I bring each circuit back online by installing each fuse one at a time in the always hot fuse panel the test light doesn't come on.
However, when I turn ignition key on to activate the accessory fuse panel my tach needle swings way upward, even when I remove the fuse for the tach. circuit. This causes my test light to light up whether the fuse is in or not. But when I put the battery cable back on the tach. reacts normally. Is the tach. my problem, maybe a bad ground? Or, should the power lead for the tach. go directly to the switchable side of the ignition rather than through the accessory fuse panel?

CORRECTION: What I was describing as my tach. wire is actually the wire for my electronic speedo. When I hook up positive battery cable to the battery everything on accessory panel operates as it should. Leaning towards a battery problem.
 
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Lots of electronic stuff today have smoothing caps and spark shortly while charging up after sitting unplugged.
The only real way to catch a drain is with a milliamp meter measuring each circuit.
Get a DMM most even the cheap one has an ammeter.
Take out the fuses and measure each circuit.
 
flatheadmurre said:
Lots of electronic stuff today have smoothing caps and spark shortly while charging up after sitting unplugged.
The only real way to catch a drain is with a milliamp meter measuring each circuit.
Get a DMM most even the cheap one has an ammeter.
Take out the fuses and measure each circuit.
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I have a multi-meter but am not electronically savvy, what do I set the dial selector on and what numerical value am I looking for to confirm the drain?
 
Set it for measuring current should say A or mA for milliamp.
Then measure across where the fuse was taken out.
If you get a reading there something is drawing current.
 
remove all the fuses from the fuse block and see if that cures the drain. then put in one fuse at a time removing it as you find out if that is or is not where the drain is...
 
donald1950 said:
remove all the fuses from the fuse block and see if that cures the drain. then put in one fuse at a time removing it as you find out if that is or is not where the drain is...
Click to expand...
That I have already done with test light, never could get the light to come on as I brought each circuit back online by installing one fuse at a time.
 
Remove all fuses.
Lift the battery pole and measure between battery and cable for current.
You get a reading there you have to start investigating generator/regulator or something else in primary circuit.
If you got no current reading there install battery pole again and measure over each fuseholder until you find where current is drawn.
 
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