Battery runs down

[Roadster!]

Any suggestions , my 67 battery constantly runs low, if it sits more than a week I can hardly start it and have to charge it when I know i am
going to drive it for weekend or something...Its been going on for years............... And no its not the battery itself....
Must have an open circuit somewhere but dont know how to look for it

[nismou20]

How's the starter? Can get weak over many years. I was chasing down similar issues replacing cables, grounding, and found out starter just got tired. Open circuit should not draw power. Those HF floating chargers work great if battery is good. Keeps it at constant 12.6 minimal amp draw.

If you want to get dirty you'll most likely have to pull one fuse at a time and look for VDC drop over time.

[redroadster]

Discon the neg cable hook in a multimeter with a 10 -20 amp range
check mil-amps . todays cars draw,14- 30
You did a electronic load test ?

[Roadster!]

So I just did a voltage light test, I disconnected the neg terminal and connected a light to the teminal and cable, light remained constant...took out all the fuses one by one and light stayed on.......... am I missing something? my car is early modle with only 4 fuses

[garth]

So I just did a voltage light test, I disconnected the neg terminal and connected a light to the teminal and cable, light remained constant...took out all the fuses one by one and light stayed on.......... am I missing something? my car is early modle with only 4 fuses

Redroadster's test is more sensitive. Measure current draw separately with each fuse in.

For reference; my 69 roadster draws 4.5 mA with the clock as the only load and takes about 3 weeks to drain the battery down to 12.00 volts. I have a gear type replacement starter that will crank the engine to start with a battery voltage of 11.20 Volts.

Good luck finding the gremlin(s).

[fj20spl311]

If the wiring is stock,
Only the radio and ign switch is unfused.

[Curtis]

Best best is a maintenance charger. Keeps the battery healthy and got rid of the run down. Even with forgetting to put water in my original type group 53 battery I still got 5-6 years out of it.

At $180 for a new one I decided to switch to a group 51. Almost twice the battery for less money and gives a little more room in that area. What was funny is my first car was a 63 factory turbocharged Corvair Spyder and it used the same group 53 battery tucked away on the side of the engine compartment. And it was easy to run down too.