Charging issue?
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Joined: Sep 2006
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From: NC
Charging issue?
I have something that concerns me a little about my truck. When I first start it up I noticed that the lights stay dim and the alt guage is very low for a little while. When it kicks in the lights brighten up and the guage goes to normal.
It's my understanding that the voltage regulator regulates when the alternator needs to send voltage and when not to. Is this correct?
If this is correct, then I would think that just after cranking the alternator should be up pretty high.
Could this be a voltage regulator going bad? I wouldn't think the armeture or the brushes because if it was one of them then it should be doing it all the time.
Any thoughts would be appreciated.
It's my understanding that the voltage regulator regulates when the alternator needs to send voltage and when not to. Is this correct?
If this is correct, then I would think that just after cranking the alternator should be up pretty high.
Could this be a voltage regulator going bad? I wouldn't think the armeture or the brushes because if it was one of them then it should be doing it all the time.
Any thoughts would be appreciated.
Posting Guru
Joined: Nov 2007
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From: West Texas
It's just the glow plugs drawing a lot of amps. When the glow plug relay turns off then everything brightens up. If you have fresh batteries and good clean and tight connections it will minimize how much you notice it.
Postmaster
Joined: Feb 2004
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From: Levittown
Give me some of what your drinking!!!
Agree. The charging system is at max. Then it spikes as the gp's go off.
It elevates more as batts age. (higher voltage drop).
Bill
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From: Levittown
I changed my mind. I want what Tj was drinking!!!
I need some antifreeze in me!!!
Bill
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Hotshot
Joined: Aug 2006
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IIRC .. It had to do with too much strain on the charging system starter just being used & while the GP'S were heating up ...Made sense to me ...
And the back of the seat was hot ...(remind me to tell you that story )
And the back of the seat was hot ...(remind me to tell you that story )
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Fleet Mechanic
Joined: Aug 2007
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From: The boonies by Dallas OR
On our trucks the alternator output is ~90 A at idle and 130-150A at high RPM. The glow plugs draw 160 to 180 A. The lights dim down because the glow plugs draw more than the alternator can output leaving a heavy draw on the battery. Once the glow plugs turn off the alternator can bring the system up to 14.2V.
On the sooperdoody dual alternator systems, ONE of the two alternators is disabled while the glow plugs are on. On the dual system the alternators can crank out more than glow plugs. If both alts were on when the glow plugs shut down, the voltage would surge so high that it would blow things up so Ford only lets one run.
Hotshot
Joined: Aug 2006
Posts: 10,764
Likes: 39
You're getting confused by sooperdoody truck dual alternator systems.
On our trucks the alternator output is ~90 A at idle and 130-150A at high RPM. The glow plugs draw 160 to 180 A. The lights dim down because the glow plugs draw more than the alternator can output leaving a heavy draw on the battery. Once the glow plugs turn off the alternator can bring the system up to 14.2V.
On the sooperdoody dual alternator systems, ONE of the two alternators is disabled while the glow plugs are on. On the dual system the alternators can crank out more than glow plugs. If both alts were on when the glow plugs shut down, the voltage would surge so high that it would blow things up so Ford only lets one run.
On our trucks the alternator output is ~90 A at idle and 130-150A at high RPM. The glow plugs draw 160 to 180 A. The lights dim down because the glow plugs draw more than the alternator can output leaving a heavy draw on the battery. Once the glow plugs turn off the alternator can bring the system up to 14.2V.
On the sooperdoody dual alternator systems, ONE of the two alternators is disabled while the glow plugs are on. On the dual system the alternators can crank out more than glow plugs. If both alts were on when the glow plugs shut down, the voltage would surge so high that it would blow things up so Ford only lets one run.
Keep in mind ..., I can hide my own Easter eggs .....
