Electrical drain, battery won't maintain charge?
 

I have a 12V negative ground electrical system system with alternator in my '36. Am told that I should not see sparks at all when hooking up battery cables; I do whenever I hook up the positive cable. I have two fuse panels, one for switchable accessories and one for circuits that remain hot. I have pulled the fuses one at a time for all circuits but continue to get spark at positive cable. where do I go from here?

Re: Electrical drain, battery won't maintain charge?
 

Take the feed wires off the fuse panel one at at time. Maybe there is a low grade short in one side of the panel.

Re: Electrical drain, battery won't maintain charge?
 

unhook the alternator, check again for spark. if no spark, bad diode in alternator. modern radio's have a memory too, but thats a very small draw

Re: Electrical drain, battery won't maintain charge?
 

Hydraulic brake light switch can sometimes fail with the connection "made", but not able to pass enough current to light the bulb filaments.

Re: Electrical drain, battery won't maintain charge?
 

Previously, couple years ago did have diode in alternator replaced when having an electrical problem, cable still sparks with alternator wire disconnected. What I did find was that when I disconnected feed from my 50 amp circuit breaker to the fuse panel that is hot all the time the battery cable no longer sparks. Yet, when I fail each circuit by removing the fuse for each circuit the battery continues to spark. So, are we talking about a "low grade" short here? It does take a few days to knock the battery down where it doesn't have sufficient voltage to crank and the spark at the cable is very slight.
What would be my next step?

Re: Electrical drain, battery won't maintain charge?
 

Do you have one of those "free" harboe freight multimeters??, they have a 10 amp scale
Some of the electronics that have 2 power feeds can draw when one is unhooked

stock cars have known componets, it is easier becauser the systewm in known, on modified cars only the person that modified knows what was done

Re: Electrical drain, battery won't maintain charge?
 

First I would disconnect the feed TO the circuit breaker and check for draw. If it still has the drain, go back toward the source at every connection until there is no drain.

EDIT: I didn't read your last post correctly. When you disconnected the fuse panel, the drain went away. So your circuit is good to that point. You either didn't remove the faulty circuit from the panel or the panel is partially shorted to ground. Remove the fasteners that connect the panel to the car and make sure that the fuse panel isn't touching the car's metal anywhere and recheck. If it is still has the spark you didn't remove something from the panel when checking previously.

More thoughts: Maybe you have more than one appliance in the car that has a memory draw. Try removing all the fuses from that panel at one time and see if you still have the drain.

Re: Electrical drain, battery won't maintain charge?
 

Will give it a go tomorrow

Re: Electrical drain, battery won't maintain charge?
 

When confronted by errant current drain, I like to remove all easily available battery connections and fuses then test - add back one circuit - test - add back another circuit - test ... proceeding a small circuit at a time.

Quite often the drain is beyond what you see as 'everything' which really isn't everything but is really your idea of everything so you become mislead and overlook the real problem. So if you simply remove a tiny bit then test you will miss the real problem or waste gobs of time finding the drain.

I like what someone suggested using the I or current metering on an electrical meter. If you aren't sure you know what you are doing, many are willing to show you, it's a good ability to know. Doing a hunt this way can go quickly if you have a 'meter watcher' to call out anomalies as you add back fuses etc.

Incidentally, common problems are bad diodes inthe alternator regulator and the radio.

Re: Electrical drain, battery won't maintain charge?
 

You can have a large seeming spark when hooking up the battery cable but the draw can be nothing when a capacitor in some electronics is charging---you need to use a meter to know how much of a draw

Re: Electrical drain, battery won't maintain charge?
 

if you have a chevy one wire alt, they have been known not to break the charging circuit in the alt and it stays hot when engine is turned off, will drain batt over night

Re: Electrical drain, battery won't maintain charge?
 

Nope, it's a two wire alternator.

Re: Electrical drain, battery won't maintain charge?
 

Is all the wiring new and yours, or is some of it original Ford style? What are you doing for the main headlight switches and brake lights?

Re: Electrical drain, battery won't maintain charge?
 

If you disconnect power to the fuse panel there is no draw but the individual circuits disconnected do not remedy anything then I would look for a short in the fuse box.

Re: Electrical drain, battery won't maintain charge?
 

Make sure something hasn't dropped behind the fuse panel (metal shaving, etc) and is causing the short. Or a wire has come loose from a contact and is touching another wire. Had this happen some years back with an aftermarket panel. Fond the problem after I removed the panel from it's mounting.u

Re: Electrical drain, battery won't maintain charge?
 

My two fuse blocks are made of plastic and our mounted to the vinyl covered kick panels, the mounting screws on the backside don't make contact with the metal bracing/reinforcement in the opening for the kick panel.
The power supply for my main circuit breaker comes from the post on the starter. On the other side of the breaker a line goes to the panel that is hot all the time. Another line runs from the power source post for the breaker to the hot side of the ignition switch. Then a wire from the switchable side of the ignition runs to the accessory fuse panel. Also, from the
switchable side of the ignition the wire to the alternator is located. Thought this might be useful info..

Re: Electrical drain, battery won't maintain charge?
 

You sure about that? That post would only be "hot" while starter is cranking engine. DD

Re: Electrical drain, battery won't maintain charge?
 

I should have stated that I have an aftermarket starter that has a built in solenoid, the post is always hot.
Also, I misstated the power source for the hot panel, it actually gets its power from the switchable/demand side of the circuit breaker.

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

Since the spark goes away when you de-energize that fuse block, the source of the drain is in the block itself or one/more of the circuits from it. Have you removed ALL the fuses from the block (at one time) and checked for a spark? Have you put a volt meter between the battery post and the removed cable?

Re: Electrical drain, battery won't maintain charge?
 

All new wiring

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

Have you hooked a multi-meter in series with the positive cable to get an amp reading.

Bob

Re: Electrical drain, battery won't maintain charge?
 

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?

Re: Electrical drain, battery won't maintain charge?
 

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?

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

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?

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

Do you have a modern radio with a memory? They draw all the time.

Re: Electrical drain, battery won't maintain charge?
 

Not a radio per se but an amp for Bluetooth.

Re: Electrical drain, battery won't maintain charge?
 

What happened with the battery test?

Re: Electrical drain, battery won't maintain charge?
 

Am 73, I talk a good game but not much follow through; it's cold, battery is heavy and located behind back seat, will investigate further less labor intense tests!

Re: Electrical drain, battery won't maintain charge?
 

Love the answer! :)

Re: Electrical drain, battery won't maintain charge?
 

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...

Re: Electrical drain, battery won't maintain charge?
 

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.

Re: Electrical drain, battery won't maintain charge?
 

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.