Chasing a short

[74DDS]

Hey I've spent the last two weekends running laps around my car to try to find a short that caused my battery drain it self. I have just recently mounted the battery in the trunk and installed a master kill switch.  I have the switch and battery in all summer and never had a problem like this, so now I'm drawing a blank on what the problem is, I thought it was the voltage regulator but after testing my dads I found out that they are suposed to be grounded. The master kill switch that I installed is the 4 post kind and I ran the field wires to it to kill the car and I've checked the wires going to the switch multiple times and they are not shorting out, so I have come to you seeking advice on what else could be problematic with these old mopars. I'd like to get the car out atleast once or twice more before I put it away for the winter and do my motor swap. So please help.Thanks.

[68S]

Did you try disconnecting the battery cables then checking the voltage after it sat for a while to be sure the battery is not internally shorted? If the battery checks out ok your best bet is to disconnect one of the battery cables and attach a test light between the unused battery post and the cable you just disconnected. Lets say you chose to disconnect the positive terminal; you would then attach one end of the test light to the positive battery terminal and the other end of the test light to the positive battery cable. If there is a short the test light should glow. The intensity of the test light's brightness will be dependant on the size of the short so don't think all is well if the test light only barely lights up. Now for the fun part. If you have attached the test light and it glows, indicating a short, you will need to start disconnecting fuses from the fuse box or disconnecting components until the light goes out. Once the light goes out you then need to trace whatever is on that circuit to find the short. I should say that you could also use a volt/ohm meter hooked up in the same way and it would be much more accurate but for the most part the test light method works fine.

Hope this helps,

Pat

[HemiDemon]

I would like to add a bit to the good advise Pat gave you. If that test light comes on, try disconnecting the alternator output lead from the alternator. A leaky or shorted diode in the alternator could drain the battery too.

Good Luck,
Bruce

[74DDS]

Would that be possible with a new alternator, cuz I installed one early in the spring.

[Jim_Lusk]

Would that be possible with a new alternator, cuz I installed one early in the spring.

Yes, a "new" alternator could be bad.