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Charging issues

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Old Oct 18, 2007 | 09:04 PM
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Default Charging issues

Well it looks like I won't be taking the Shark to Sharktoberfest. While I was looking into the charging issue I noticed that the volt meter wasn't reading anything. I will jump when I start the car but it stays low. Checked with the volt meter and it was reading below 11volts. Using some jumpers I connected my truck to it ant it read about 13volts. Disconnecting the jumper cables it'd drop back down to about 10.5volts and it wouldn't even move when I revved the engine. Yup alternator isn't charging.

Getting kind of old as I changed the dang thing last year too. Guess I'll have to pick one up at 928int this weekend.

Damn I was really looking forward to the drive up.
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Old Oct 21, 2007 | 11:51 AM
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If your cooling tube and alt cover are intact...
Probably just the regulator -not cheap in it's own right.
Unless you smoked some diodes.
Check your ground cable!
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Old Oct 21, 2007 | 04:54 PM
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Bret--

Pull the battery and charge it out of the car with a real charger. Top off each cell as needed with distilled water before you charge, of course. Then check the voltage after charging. Wait half an hour or so after the charger is removed to get a valid resting reading. Should be 12.5 or so just sitting there. Each cell contributes 2 volts or so, so a dead cell will cause the reading to drop by 2 volts. A dead cell forces the alternator to work extra hard, perhaps beyond its capaicity. That contributes to early failure of course.

With the battery charged and still out of the car, check the specific gravity of the fluid in each cell. The little floating-ball checker is less than $2 at Wal-Mart and most parts stores.

Useful battery life is probably four years for the way most of us use our cars. Some will last more and some less obviously. Many peple try to wring extra life from a battery that should be replaced, at the expense of other related components like the alternator. Point is, don't be afraid to buy a battery if there's a hint that it's needed. It's a net money and timesaver.
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Old Oct 21, 2007 | 04:55 PM
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Does the light on the volt meter in the dash come on when the key is turned to the run position, with the engine shut off?
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Old Oct 21, 2007 | 06:34 PM
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First check that the dash gauge is reading true battery volts. I just went through this scare about failing alternator, but it was just a bad reading, and an old battery - 6 years is a pretty fair life I guess. New battery fixed everything .
jp 83 Euro S AT 51k
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Old Oct 22, 2007 | 01:09 AM
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Thanks everyone. Actually I checked the battery but I think I like Bob's idea about removing it and having it charged while I replace the alternator I picked up over the weekend at Sharktoberfest and think I'll take it down to the local auto shop to be re charged while I swap out the old alternator.

Anyway just so ya'll know I did a couple of different tests and am 99% sure its' a dead Alternator. I connected (jumpered) my truck to the battery and the meter actually reads pretty good. Likewise when I rev the truck's engine the guage pod's voltage meter tracks right along with the volt meter I have across the battery. But disconnecting the jumper cables the battery stays at a constant 11.5-12volts with the engine on or off. Likewise if I rev the shark's engine I see no change and at an idle with a low battery I should see between 13-14volts (charging) with a slight increase (albit regulated) to about ~15volts.

Kind of a bummer actually considering it was a rebuilt unit that I purchased a little over a year ago. So this time I popped for the extra coinage and got a new unit. With a little luck I hope to have it installed later this week depending on my work schedule.
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Old Nov 6, 2007 | 10:36 AM
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Update!

After a week of on & off again evacuations because of the fires, a still yet to be determined illness with my son and the ex having to fly out of town back to PA because of a death in her family leaving me to play Mr. Mom all last week - I finally got some time to install that "new" alternator I picked up at Sharktoberfest before all the crap hit the fan. Yea me! Whohooo!

So far the shark seems to be running great, but I think I’ve got (or had) a coolant leak someplace that I suspect is was caused or contributed to the Alternator to go belly up. Of course this could just be the reminisce of the last leaky radiator hose that had a pin hole leak that was (under pressure) spraying down the whole front of the engine – including the alternator.

Oh well - I'll keep my eye on it an enjoy having it back on the road again.
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Old Nov 6, 2007 | 02:30 PM
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Good to know you have it working !
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