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Old 10-18-2004, 05:33 PM
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boneheaddoctor boneheaddoctor is offline
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Join Date: May 2004
Location: Hells half acre (Great Falls, Virginia)
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Quote:
Originally Posted by GregS
I have a problem that I can't quite figure out, so hopefully someone here can shed some light: when I spend a Saturday or Sunday running errands and making lots of short trips, eventually my battery runs down a lot. I know this because 1) the engine is cranking over noticeably slower, and 2) I can measure battery charge with a multimeter and it will read 12.24 volts, which is really low. I thought maybe I have a charging problem, but at idle I have around 13.85 volts, and around 13.95 at fast idle. I think that should be enough to keep the battery charged, shouldn't it? Because the alternator was charging properly I suspected the battery, and replaced it. Unfotunately, I had the same problem this past weekend, even to the point where the battery had barely enough juice to crank the engine. Can anyone suggest what the problem might be?

Here is the other piece of this puzzle. I know my starter is having problems because sometimes I will turn the key and nothing will happen. If I tap the side of the starter solenoid it will start. I guess this is a sign that the solenoid is going bad. But here is my ultimate question - is the fact that the starter is going bad the cause of my battery problems? I'm thinking that because the starter is going bad, its drawing more current than it normally would, and therefore lots of stopping and restarting the engine is running down the battery.

I would appreciate any advice. Maybe someone has had a similar problem. BTW, all battery cables and connections are clean.

Thanks,

GregS
'84 300D
I had a regulator that sometimes overcharged (17.9 volts measured at battery post once, thats when I ordered a new one when I got home) smoked the Tach, half the dash lights and stereo, sometimes never charged and on 4 occaisions drained the battery overnight for no reason whatsoever. This was over the course of 8 months.

About the starter, check your connections first.
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