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Old Sep 18, 2013 | 03:30 PM
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I get - testing off the battery terminals - 13.4 volts consistently at anything above 2500 rpm. Is that enough? Or is my alternator weak? What do you see on yours, those of you that have tested...
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Old Sep 18, 2013 | 03:37 PM
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Seems weak. I think you want around 13.8. My freshly rebuilt alternator charges low 14s.
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Old Sep 18, 2013 | 03:40 PM
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Some numeric discussion here.
http://forums.pelicanparts.com/porsc...tor-993-a.html
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Old Sep 18, 2013 | 04:09 PM
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I typically get 13.8 volts. What is the voltage of your battery with the engine off? A low battery can pull down the voltage until the battery is fully charged.
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Old Sep 18, 2013 | 04:47 PM
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I just realized that my alternator was bad and the reason for my glitches with the throttle down on track. The coils doesn't get enough power. It's output is 13,1 and Adrians book says 13,8-14,4 at idle, or at least at 1200 rpms. Som mine is now going for a rebuild.

Thomas
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Old Sep 18, 2013 | 05:18 PM
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battery alone was 12.3-12.5 ish - would jump a little - but then at 3000 rpm was fixed firm at 13.4

So yeah - I was thinking it was weak. Next question is - fully rebuilt alternator from pelican for 250? Or just the voltage regulator?
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Old Sep 18, 2013 | 05:22 PM
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I had mine rebuilt by a local alternator shop for less than $150.
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Old Sep 18, 2013 | 11:10 PM
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Did RS single belt pulley will get lower readings?
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