Some draw with key off

daveymc29

daveymc29

Well-known member
I run a pop out ignition, fuze by the starter. Twice I found the battery dead so the last time I checked the fuse holder with the circuit breaker removed. I did not get an amperage reading, voltage reading is a bit over 6V. I use a circuit breaker and as I was replacing it, I saw an obvious spark. Seemed to me something is creating a draw but no reading on the amp meter. So what am I missing? It will kill the battery overnight. I am also running an alternator, 6V positive ground.
 
The starter should be the only thing not going through your fuse. From the fuse the power goes to the ammeter and out to the horn, lights, coil and generator, so they should show a draw on the ammeter if they are on or shorted. The coil was wired to not show through the ammeter however, until the end of 1929. On my 28 Phaeton I switch my black coil wire to the other terminal box stud, so it would show through the ammeter.

I'd remove the instrument panel and see if the ignition switch or ammeter terminals are touching ground. Sometimes the insulation inside the ammeter goes bad and can let the power short to ground.
 
Also a reproduction junction box can short to the firewall. And the fuse holder is not the best. I found the fuse holder insulators are a problem, or the screws to attach the fuseholder and starter switch can be a bit too long.
 
sometimes an alternator will cause that to happen. unhook the two wires from your alt, but keep the two wires hook to each other.and see what it does overnight.
 
Single wire converted alternators have a slight parasitic draw.But,overnight is too much.I have some on old loaders,farm tractors,and a dozer.They will hold weeks at a time with a slight draw.Unhook things one at a time.and check to see if your spark is still there.I found one a couple of weeks ago where the horn contact in the repro wiring harness was too big.It was just a couple of thousandths from the inside sleeve on the light switch,id wasn't quite a dead short,but it would drain the battery,so it must have been arcing to ground.We had the drain narrowed down to the light switch,when one guy was rubbing the horn talking about how nice it was.He also noticed it was warmer than the rest of the metal around it.
 
I use a switch under the dash that disconnects the wire from the starter switch to the terminal box. The alternator will often draw a small amount and eventually discharge the battery.
 
daveymc29 said:
I run a pop out ignition, fuze by the starter. Twice I found the battery dead so the last time I checked the fuse holder with the circuit breaker removed. I did not get an amperage reading, voltage reading is a bit over 6V. I use a circuit breaker and as I was replacing it, I saw an obvious spark. Seemed to me something is creating a draw but no reading on the amp meter. So what am I missing? It will kill the battery overnight. I am also running an alternator, 6V positive ground.
Click to expand...

Your post says that you saw a spark, but no amp reading. That doesn't make sense. Did you use a low scale on the meter ?

Marc
 
I understand that doesn't make sense. Thus the post. Just wondered what I'm missing. Perhaps my multimeter is bad. I'll have to try to measure a known draw. Thanks for all the tips.
 
If your problem is in the popout,and the feed wire is on the wrong side in the terminal box,it won't show up on the ammeter.I think it is in the service bulletins showing how Ford switched the wire over to make ignition drain go through the meter.If it drains overnight,that is enough to show up on the meter.The normal parasitic drain from the alternator shouldn't do that in that amount of time,UNLESS,your battery is marginal.New doesn't mean good,and we're noticing that tractor supply batteries don't seem to hold up well when sitting around a lot.
 
Whoever installed the ammeter may have bypassed the ammeter because of the higher amperage out of the alternator.
 
The car hasn't had a charging or dead battery problem until just the last week so this is new. No work has been done on any part of it in months. All was well until one morning I tried to start it and found the battery completely dead. I thought at the time that I may have inadvertently left the ignition on. sometimes when I shut it off if I'm not careful the pop out will, well Pop Out. So after the first dead battery, (six months old Optima 6V) I made really sure that the key was off and the pop out had stayed pushed in, still a dead battery the following morning so I now pull the circuit breaker and have seen a spark almost every time pulling or putting it back in the fuse holder. I'm going to follow up by pulling the alternator wire and checking, then move on to a possible coil problem. I do not get a neg. reading on the amp meter when everything is off, but do when I turn the key on and that has been the case since I moved the black coil wire to show a reading when the key is on, years ago. Perhaps sitting overnight with the key in the "on" position may have damaged the coil some. The car seems a bit hesitant when running the last week or so since the dead battery problem showed up. Any quick coil test out there?
 
Just remove a battery terminal and attach a test light or voltmeter between the cable and terminal. If the light lights [or voltmeter registers], there is a draw. Keep disconnecting things until the light goes out.
A very common draw is the brake light switch sticking on which should show on the ammeter, but, after all the years one never knows how it, or anything, may be wired.
 
Disconnect the black power wire to the coil, then connect a test light or volt meter between the wire and coil terminal. If you get a voltage reading, then disconnect the red wire from the coil terminal and see if the black wire still shows a voltage reading with the volt meter connected to the coil - terminal and black wire. If you get a reading, then the coil must be shorted to ground.
 
Thanks Tom, tomorrows test on the to do list. Yesterday was new water heater purchase and installation. Today taking the bind out of a few doors that became stuck or sticking with the last two weeks of earthquake swarms. A 3.2 real close is the one I suspect, but barring some other priority I will follow this up tomorrow afternoon. Thanks all for bearing with me. Old age keeps me occupied. Used to do these things in minutes, now take hours if I can remember how to do them.
 
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