testing battery/alt
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More Turbo
Joined: Dec 2004
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From: Jamestown Tn
testing battery/alt
My truck has started slower than normal the last 2 days after sitting overnight. I was thinking it may be the battery or Alt. But the both batteries were new in 2010 (duralast gold) I also replace the Alt last year. and a new starter 2 months ago. I just checked with the multimeter 12.72 bot read when truck is off. running it went to 14.3 then 13.9 when lights and fan heater were all on the same time. Is the only way to test a single battery is to load test it? I think one battery will fill in for the other if one of them is low because they are both connected. Is that correct? if so I can have AutoZone do a load test on each one to verify that. I just don't want to be left in the dark somewhere. I did clean the post just before this started and Im wondering if I need to re clean them again. I know they are pretty sensitive. thanks Jeff
Go Bills !
Joined: Jan 2008
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From: Buffalo, NY
Alternator is fine. You can always stop i at autozone to load test the batteries. If one battery has took a dump you won't know it unless you test them.
Maybe your new starter is a "dog" when it is cold. Was it a reman starter? Cables to that nice and clean?
Maybe your new starter is a "dog" when it is cold. Was it a reman starter? Cables to that nice and clean?
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Joined: Dec 2004
Posts: 527
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From: Jamestown Tn
The new starter is a rebuilt one from fleetpride. It was spinning like a jet engine since i installed it. I will get the batts load tested today to eliminate that possibility. Then i will recheck the starter connectioins etc. thanks jeff m
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From: Jenkintown, PA
Chris
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Joined: Dec 2004
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From: Jamestown Tn
Had them load tested last night both at 100% alt good as well. I recleaned the post and reseated them again fixed the problem. Seems a good solid connection is VERY important to have a good voltage flow. thanks
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Joined: Sep 2011
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From: Delaware
Unfortunately, it's just the opposite. When a good battery is connected to a bad one it will discharge until the voltages of both are equal. It's sort of like connecting two tanks of water, one full and one at half. The water will seek its own level until both tanks are the same. That's one of the fundamental problems of dual batteries connected in parallel, and is the reason behind the many posts you will see that recommend replacing batteries in pairs.
Chris
Chris
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