Low voltage
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Senior User
Joined: Mar 2009
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From: Bartlett, Tn (Memphis)
Low voltage
Well a while back I bought two new batteries cause the ones in it were seeming to not turn the truck over and seemed like they were dead after about a week of sitting time. So I went to napa tested bad. Replaced both. Well after about the second time trying to start it it seemed weak again. So I had the alt. Tested. Said it was bad. Ok. So I got an alternator on it now. Charging good now. Let it sit for a week and it barely starts the truck. One thing is I thought I checked voltage on batteries but I left them connected. I need to isolate them and recheck. When I pull the ground wire off I don't see a spark or anything that seemed like it's still drawing power.
The truck sits for a week at a time atleast. When I try to start it the gauge inside goes to a out 9v. Eventuay starts and runs rough for a bit. I know these trucks like good batteries. Is it possible I'm only feeding the truck from one battery? Anything else common to this?
The truck sits for a week at a time atleast. When I try to start it the gauge inside goes to a out 9v. Eventuay starts and runs rough for a bit. I know these trucks like good batteries. Is it possible I'm only feeding the truck from one battery? Anything else common to this?
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Joined: Jan 2010
Posts: 10,060
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From: Bristol, TN.
Well a while back I bought two new batteries cause the ones in it were seeming to not turn the truck over and seemed like they were dead after about a week of sitting time. So I went to napa tested bad. Replaced both. Well after about the second time trying to start it it seemed weak again. So I had the alt. Tested. Said it was bad. Ok. So I got an alternator on it now. Charging good now. Let it sit for a week and it barely starts the truck. One thing is I thought I checked voltage on batteries but I left them connected. I need to isolate them and recheck. When I pull the ground wire off I don't see a spark or anything that seemed like it's still drawing power.
The truck sits for a week at a time atleast. When I try to start it the gauge inside goes to a out 9v. Eventuay starts and runs rough for a bit. I know these trucks like good batteries. Is it possible I'm only feeding the truck from one battery? Anything else common to this?
The truck sits for a week at a time atleast. When I try to start it the gauge inside goes to a out 9v. Eventuay starts and runs rough for a bit. I know these trucks like good batteries. Is it possible I'm only feeding the truck from one battery? Anything else common to this?
I would also recheck all connections. Whenever something doesn't work after I fixed it, I go back to what I fixed last.
You may be right about trying to start on only one battery as a voltage draw down under load is often symptomatic of a poor connection. Low voltage may also be responsible for the ragged running when first started.
Steve
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Joined: Jan 2008
Posts: 13,144
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From: Rochdale MA
Just for the hell of it in the am after the truck has set for the night feel the alt and see if it is warm or slightly warmer than the ambient temp) I have seen rebuilt alts test good but the diode in them is leaking causing a drain on the battery.
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Senior User
Joined: Mar 2009
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From: Bartlett, Tn (Memphis)
Good points thanks. I'll check this out. What should the "sitting" amp draw be. Next to nothing?
Well as far as going back to what I fixed. I'll look at it for sure but I'm thinking I had a problem before the alt was put on. I do want to swap out the battery terminal on one of the batteries though. It was weird kind that I guess you use for stereo systems and such. Not sure. Tightens with an Allen wrench. I don't like it. So I'll swap it out for peice of mind.
Well as far as going back to what I fixed. I'll look at it for sure but I'm thinking I had a problem before the alt was put on. I do want to swap out the battery terminal on one of the batteries though. It was weird kind that I guess you use for stereo systems and such. Not sure. Tightens with an Allen wrench. I don't like it. So I'll swap it out for peice of mind.
Thread Starter
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Senior User
Joined: Mar 2009
Posts: 124
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From: Bartlett, Tn (Memphis)
ok, so i had time to get out there and mess with it. turns out it is faulty battery terminal. there was one on the truck when i got it. to me looked like something they would have had for a stereo system or some such. not sure. anyways, at the battery was one voltage. out the wire was another, (lower). and it was trying to run on one battery and it is running better and starts a whole lot better, ha ha.
thanks for the tips. just thought id post the results.
thanks for the tips. just thought id post the results.
Hotshot
Joined: Jan 2008
Posts: 13,144
Likes: 11
From: Rochdale MA
Glad that she is fixed. Connections and the cables are just as important as the batteries in our trucks!!
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Joined: Jun 2008
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From: Albuquerque
Not sure if others would recomend this, but if your doing an amp or volt draw, I pull the engine bay light. That little sucker draws enough to not get a good reading. Food for thought.
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