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| Weak alternator | |
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| Tweet Topic Started: Sep 2 2015, 02:38 PM (681 Views) | |
| MPG | Sep 2 2015, 02:38 PM Post #1 |
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How many volts should my alternator be testing Showing 12.4 volts |
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| Metromightymouse | Sep 2 2015, 02:48 PM Post #2 |
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Powdercoat Wizard
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14 some odd |
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| MPG | Sep 2 2015, 04:05 PM Post #3 |
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Hmm That explains the battery dying out 😕. Thankx MMM 😀 Guess I'll get it rebuilt |
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| Memphis metro | Sep 2 2015, 04:19 PM Post #4 |
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How are you measuring alternator output? Normal charging rate is 13.9-14.1 |
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| myredvert | Sep 2 2015, 04:42 PM Post #5 |
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myredvert
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The upper end decreases linearly with an increase in temperature, and with the temperature in the high 80s, close to 90 like it has been near you the last few days a hair over 14.0V for a minimum would be appropriate. |
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| MPG | Sep 12 2015, 10:15 AM Post #6 |
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Tester clamped on alternator lugs with engine at an idle |
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| Old Man | Sep 12 2015, 11:05 AM Post #7 |
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Try reving to about 1000 RPM. My lights etc go dim at an idle because the alternator is not at its efficiency at that low RPM. Just as soon as I get a little above idle the lights go brighter indicating that the alternator is more efficient at a little higher RPM EDIT; If that gives you better voltage then go to your battery for the same test. If it is considerably lower at the battery then start cleaning wire connections/grounds/replacing wires. Edited by Old Man, Sep 12 2015, 11:06 AM.
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| myredvert | Sep 12 2015, 11:09 AM Post #8 |
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myredvert
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The Factory Service Manual test in in post #5. Voltmeter connected to the battery. The FSM doesn't specify what "moderate rpm" is, but I would follow Old Man's advice and use a minimum of 1000 if not more. |
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| MPG | Sep 12 2015, 12:00 PM Post #9 |
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Will try your suggestions Thankx Old man & redvert
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Will try your suggestions Thankx Old man & redvert
2:13 PM Jul 11