Voltage drop - then dead
05-08-2004, 12:30 AM
#1
Race Car
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Location: Salem, OR (this place is a sh!t hole)
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Voltage drop - then dead
Well, it looks like the electricl gods are upset with me again.
Here's the skinny: my volt meter in the car showed a drop from the normal ~13 volts to just under 12 volts, like my belt was slipping or something. It slowly dropped to 10 volts and then went sub-10 while still running.
I pulled into my friend's house to let the car cool off thinking that it just got WAY too hot. (it was extremely hot in Atlanta today) Well, I gto back to my car about two hours later, it cranked and I drove off. Well, I got about a mile and the thing died on me.
So, here's what I think: I took a voltage reading at the battery (brand new tonight. The reading: 12.05 volts. 1-2 volts lower than what it should be. My belt has not come off the pully and it is tight and the pully is turning. I'm not sure if the voltage regulator has gone bad or the alternator itself. I just replaced the alternator about a year ago.
Here's the skinny: my volt meter in the car showed a drop from the normal ~13 volts to just under 12 volts, like my belt was slipping or something. It slowly dropped to 10 volts and then went sub-10 while still running.
I pulled into my friend's house to let the car cool off thinking that it just got WAY too hot. (it was extremely hot in Atlanta today) Well, I gto back to my car about two hours later, it cranked and I drove off. Well, I got about a mile and the thing died on me.So, here's what I think: I took a voltage reading at the battery (brand new tonight. The reading: 12.05 volts. 1-2 volts lower than what it should be. My belt has not come off the pully and it is tight and the pully is turning. I'm not sure if the voltage regulator has gone bad or the alternator itself. I just replaced the alternator about a year ago.
05-08-2004, 12:33 AM
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Drifting
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To check batteries, you need to check them under a small load... they can show a normal voltage, but as soon as you hook them up to a 12v lamp, the drop considerably...
Check your regulator, then grounds, and report findings...
Check your regulator, then grounds, and report findings...
05-08-2004, 12:34 AM
#3
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The alternator is either not working or the regulator is fu**ed.
05-08-2004, 12:53 AM
#4
Burning Brakes
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They are upset with me as well so don't feel alone.....
I replaced the rectifier in my alternator (it's what the test set said was bad) and the regulator just because I had it out and wanted an adjustable one.
Alternator has been recently rebuilt, bearings are same as new ect....
put it back in the car, cranked it up.....measured voltage at the battery while running....11.9
fark
I replaced the rectifier in my alternator (it's what the test set said was bad) and the regulator just because I had it out and wanted an adjustable one.
Alternator has been recently rebuilt, bearings are same as new ect....
put it back in the car, cranked it up.....measured voltage at the battery while running....11.9
fark
05-08-2004, 01:20 AM
#5
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Adam 11.9 is too low. BTW was the battery hooked up when you read.
05-08-2004, 01:44 AM
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Unless you took your alternator to a local reputable rebuilder you most likely got a marginal replacement. Sounds like it ate the regulator brushes. This happens when the commutators are not properly turned and cleaned.
