Overcharging Alternator(s)??
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From: South Shore, MA
Overcharging Alternator(s)??
A few nights back I thought I saw my headlight brightness changing while driving - could have been the road / shadows playing tricks on my eyes. So, I scrolled through my Aeroforce Scangauge and set it to Batt Voltage.
It was mostly running around 14.6 - 14.8v. But, there'd be short bursts where the voltage would spike as high as 15.8v and hover between 15.5 - 15.8v. Then, it would settle back down into the mid 14's. Then randomly spike back up occasionally. Engine RPM had no apparent connection to the voltage spikes.
Is this cause for concern? I've never seen it run that high before.
Factory Dual Alternator truck by the way.
It was mostly running around 14.6 - 14.8v. But, there'd be short bursts where the voltage would spike as high as 15.8v and hover between 15.5 - 15.8v. Then, it would settle back down into the mid 14's. Then randomly spike back up occasionally. Engine RPM had no apparent connection to the voltage spikes.
Is this cause for concern? I've never seen it run that high before.
Factory Dual Alternator truck by the way.
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This seams like good info: https://www.ford-trucks.com/forums/1...l#post13432231
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Just unplugged each alternator independently and learned that the lower (pass side) unit is the questionable alternator.
So, now what? Should I consider replacing the voltage regulator? Or the entire unit?
So, now what? Should I consider replacing the voltage regulator? Or the entire unit?
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I'd have the alternator gone through by a rebuilder, but I'd just replace the regulator. That's what the problem was on my 6.0 140 amp, it wouldn't put out more than 13.5 volts and even then it rarely saw that. I took it to an alternator rebuilder, they replaced the regulator, and now I see a solid 13.7-14.2 volts on my scangauge.
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I'd have the alternator gone through by a rebuilder, but I'd just replace the regulator. That's what the problem was on my 6.0 140 amp, it wouldn't put out more than 13.5 volts and even then it rarely saw that. I took it to an alternator rebuilder, they replaced the regulator, and now I see a solid 13.7-14.2 volts on my scangauge.
He's asked me to take a few voltage measurements at both of the alternators, and to inspect the parallel connector under the heater box. He said he's seen a handful of them damaged from water.
I'll pull the lower alternator and have him test it too.
I'll continue to roll with the lower alt unplugged until I can find the time to pull it and bring it in.
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