Battery Drain.... !?!?!?!?!?!?

[MalibuKasey]

Ok this has me puzzled I got my '66.... and it runs like a top.... about a week ago I had a battery drain issue. So I figured a bad ground seeing how the previous owner had jiffy rigged a few things. So... I figured time to take a look. So I replaced the battery, cables, put an engine ground strap on, it needed a voltage regulator so I did that, had the Alternator tested too just cause its an old one(it was good). Soooo since then its been running great!!! well today at lunch I go to jump in it and..... click, click, click. I get a jump and viola runnin like a top until I shut it off.... so apparently I have some kind of parasitic drain on the battery.... any ideas?

[onequickchevy]

Might be as simple as a bad starter. They are cheap to replace, I would start there. Also put a voltmeter on the battery and make sure you are getting 13+ volts while running.

[low900rr]

I had a problem like that with mine. Undo the positive cable and hook a test light between the battery post and the clamp. If theres a draw the light should go on. Go to the fuse panel and start pulling fuses til the light goes off.

[daxloves]

Originally Posted by low900rr

I had a problem like that with mine. Undo the positive cable and hook a test light between the battery post and the clamp. If theres a draw the light should go on. Go to the fuse panel and start pulling fuses til the light goes off.

That is a great idea! But remember that newer stereos/CD players and clocks will draw some power so unhook them b4 testing if you have them

[67chevy2wd]

Just a thought, I had my electric choke on my carb plugged into the wrong spot on my fuse box and it was draining my battery.

[MalibuKasey]

soooo.... brand new battery and cables.... so no dirt there.... no radio at all.... electric chokes not hooked up..... and I did undo the positive cable and jump it in between the positive cable and started pulling fuses and nothing happened(all of these so far are what I thought of too)..... so still no idea. Messed with it again to night and nothing...... the battery even after pulling it out was at around 11.5 volts.... sooooooooooooooo any other ideas? It has to be something stuipid..... theres not alot to these old trucks.... but this one has got me puzzled!!!

[aerotruk63]

My Dad got me on this one, dirty battery posts on my old 62. They looked clean to me. You could jump start it, it would run, but it wouldn't start on it's own. He cleaned the battery posts without telling me and then smiled when i had to admit to being wrong in my diagnosis.

[Sillyoldman]

I'd guess a bad alternator. If its bad it can cause a reverse drain through the cable that it normally would supply. Just a guess but easy to check.

[Sillyoldman]

I didn't see that you already had it checked when I read your post. Your battery should be around 12.55v not running, and as said it should be 13+ while running. Put a volt meter on it while its running to see if it increases. I'd have to say to start chasing wires for a short.

[67chevy2wd]

Disconnect the main power wire to the starter. Maybe the starter is bad as someone said before.

[markeb01]

If there is no parasitic drain, one thing I haven't seen mentioned is the battery itself. The one you replaced may have been at the end of its service life, but the new replacement could have a cell going away internally and simply won't hold a charge. Back in the 70's I had two brand new Die Hard batteries go away in this manner. If you have a similar battery in a different car you could switch, that might eliminate another possibility. I think most parts houses will also test them for free, or certainly the place that sold it should.

[daxloves]

So if you put a fully charged battery in it stars fine, no slow turnover?

[aboz]

Had a similar problem not too long ago. The harness that runs along the driver's side inner fender panel was loose and rubbing against the clamp that is supposed to hold it. A hole was worn through brittle electrical tape (haven't rewired this baby yet) and I didn't notice it until one night after hours of trying to figure out why my new battery was draining. Because it was dark, the moment I hooked up the negative cable I thought I saw what looked a lit cigarette on the inner panel! The exposed wire was arcing against the inner fender but I never noticed it in the daytime. So my advise is...work in the dark!

[MalibuKasey]

Batterys a new interstate.... even took it back and got another one..... same prob..... the short in the wires is what I was thinking...... just need to trace everything...... and looking for it at night is prob a good idea..... Thanks everyone!!! With a fresh battery she cranks like shes new!!

[daxloves]

After its been running and you shut it off will it start back up immediately? or does it just click even tho its been running long enough to top the battery off?
If it don't start back up I would be looking at the wires between the battery and the alternator and the plug at the alternator.

[aboz]

Had the same frickin' problem today! Traced it to the crusty old horn relay. Luckily there's Bradley Auto Parts at the entrance to my neighborhood. A true independent parts store that caters to local drag racers and car enthusiasts. The owner also owns the dragstrip in Pageland, SC.! Even if it takes the better part of the afternoon to get a part, you know damn well it's the correct part for your vehicle year. Turns out that a 63-65 horn relay is a pretty hard to find part locally but their supplier had one...and only one! I tried to replace this thing over a year ago at the Auto Zone and Advance Auto. I try to avoid the big chain stores. Huge mistake every time for a truck as old as mine.

[bluesfella]

I had this same problem a few weeks ago. Took the battery in, had it tested - bad battery. New battery went in, drove fine for a day, the next morning it was dead again.

I thought it was the voltage regulator (made a funny noise when I connected the battery cable), so that got replaced. No difference.

I also replaced the battery cables, still draining.

I un-hooked the pos. cable and put a multimeter in between, there was a drain, so I just started unplugging things one at a time until it went away. It turned out to be the alternator, even though it was less than a year old.

Using a multimeter is the only way you'll know for sure what the culprit is, unless you just started randomly replacing things like I did at first...

[MalibuKasey]

So at this point im stuck....
Ive traced all the wires found a few burnt in two under the dash so I replaced those but they were just for the temp sender. I put a new horn relay on to. Just went out and checked it the battery is at 11.78 volts. So it appears the the drain is still there.... running earlier the volts were perfect.... 12.5 sitting and above 13.5 running.... so Im stumped..... I was driving it the other night and the lights started to go dim and it started cutting out.... so first thing I thought was Alt... had it tested at two different places and both of them said it was good.

[daxloves]

Originally Posted by MalibuKasey

I was driving it the other night and the lights started to go dim and it started cutting out.... so first thing I thought was Alt... had it tested at two different places and both of them said it was good.

If the alternator is good then once started you should be able to run the truck w/o a battery at all. So if the alternator IS really ok I still say you may have a bad wire between the alt and bat. May be almost broke and stops working after a fiew min when the wire warms up or doesnt work at all and you only runnin off the batt.

Does it stay running if you un hook the battery?

[bobcostas]

I've had this problem, too
Havent figured it out yet. I thought (until this post) it was just a bad ground.
But for now, i just leave it on the trickle about once a week. haha