Is my alternator going bad??

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Old Aug 7, 2017 | 08:58 PM
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Default Is my alternator going bad??

in march of this year my alternator for 17 years finally decided to go out on my camaro. so i decided to buy one from quick start high output alternators. i bought a AD244HD200 - TOP QUALITY AD244 Series, Heavy Duty, 200 Amp Alternator$299.95 Item #AD244HD200. when i installed it was reading around 14v and had been working fine till around two weeks ago. slowly but surely the voltage started to drop. as of today 8/7/17 it reads around 12.5v but if breaks are applied it will drop to 12.1v or sometimes below that. it will also jump around from 12v to 12.5-12.6v (i have a radar that reads voltage thats how i know). i just replaced the battery yesterday so i know its not the battery causing the problem. so if anyone could help i would greatly appreciate it.
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Old Aug 8, 2017 | 08:38 AM
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Make sure your positive wire connection is tight on the back of the alternator, make sure everything is snug regarding battery/grounds/etc. Plus, make sure the mounting bolts for your alternator are nice and tight (might as well)
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Old Aug 14, 2017 | 12:38 PM
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i am having the same issue..i need to check all of the grounds and may need new battery cables. My alternator is about a month old and they keep popping diodes, so something is wrong somewhere.
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Old Aug 14, 2017 | 01:48 PM
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Check cables
Pull battery, charge it, then have it tested
Pull alt and have it tested

If the battery had a cell short, it will kill the alternator in short order. Sometimes better to just replace both at once if you are short on time, both for proper diagnosis and down time. Batteries in TX only last 3 years or so, anyway, due to the heat. I like Everstart Maxx, great bang for buck at about $100. Got to spend double that to get anything much better. Your choice of alternator is a solid one.
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Old Sep 1, 2017 | 05:49 PM
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Originally Posted by tomtomLS1Z28
in march of this year my alternator for 17 years finally decided to go out on my camaro. so i decided to buy one from quick start high output alternators. i bought a AD244HD200 - TOP QUALITY AD244 Series, Heavy Duty, 200 Amp Alternator$299.95 Item #AD244HD200. when i installed it was reading around 14v and had been working fine till around two weeks ago. slowly but surely the voltage started to drop. as of today 8/7/17 it reads around 12.5v but if breaks are applied it will drop to 12.1v or sometimes below that. it will also jump around from 12v to 12.5-12.6v (i have a radar that reads voltage thats how i know). i just replaced the battery yesterday so i know its not the battery causing the problem. so if anyone could help i would greatly appreciate it.
Sounds like a bad alternator, check out my alternator thread

Originally Posted by TXjeepTJ
Make sure your positive wire connection is tight on the back of the alternator, make sure everything is snug regarding battery/grounds/etc. Plus, make sure the mounting bolts for your alternator are nice and tight (might as well)
I've seen the nut on the back of the alternator back off and cause problems before, that's a good recommendation to check there. So is the rest

Originally Posted by Taspeed
i am having the same issue..i need to check all of the grounds and may need new battery cables. My alternator is about a month old and they keep popping diodes, so something is wrong somewhere.
The replacements are absolute ****, check out my alternator thread

Originally Posted by jmilz28
Check cables
Pull battery, charge it, then have it tested
Pull alt and have it tested

If the battery had a cell short, it will kill the alternator in short order. Sometimes better to just replace both at once if you are short on time, both for proper diagnosis and down time. Batteries in TX only last 3 years or so, anyway, due to the heat. I like Everstart Maxx, great bang for buck at about $100. Got to spend double that to get anything much better. Your choice of alternator is a solid one.
I had roughly 10 in a row fail and they would test good on the bench and work like **** on the car once heat built up under the hood so use caution with the bench test. And absolutely a good recommendation to do battery and alternator at the same time, I have seen bad batteries kill good alternators.
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Old Sep 8, 2017 | 09:04 AM
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I missed that you bought a HO alt. That alone will make a part store bench test difficult at best. If it's a US build, it was probably good but a bad battery may have wrecked it. Bad battery can kill the alternator AND vice versa...I've been a victim of both. Once you take the time to check, clean, and replace cables...you may as well replace both so as not to waste the effort. Powermaster is my preferred brand of HO alt, their product is great and service is phenomenal.
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