May I assume, sir, that your battery is going dead for no apparent reason? The clock (10 ma drain ) will not run down a good battery for months. So, it's not the clock. Forget the clock. More likely than any other cause, I'd suspect the battery itself. Even if it measures 13.6 volts and turns over the engine, it may have developed an internal short. As batteries age, conductive material drops off the plates and settles to the bottom of the case. When it gets deep enough, the material shorts out the plates along the bottom. It's not a dead short, but rather a low resistance short. I've seen this happen on relatively "young" batteries, as rough physical service can aggrivate the condition. The check for this is to just dis-connect the battery from the car and find out if it goes dead on it's own in a few days time or less.

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