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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
__________________ 2002 7.3 PSD Lariat Crew Cab F-350
AIS intake w/fender mod, ISSPRO 3 guage pillar, MBRP 4" SS exhaust, Bilstien shocks, Dick Cepek Fun Country II Tires, Reverse backup sensors. ARE fiberglass hartop w/airfoil, ITP overboost Kit, BTS valve body, DP-Tuner, Powerslot Rotors/Hawk Lts pads. 6.0 Tranny cooler,Warn Premium Hubs
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?
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
__________________ 2002 7.3 PSD Lariat Crew Cab F-350
AIS intake w/fender mod, ISSPRO 3 guage pillar, MBRP 4" SS exhaust, Bilstien shocks, Dick Cepek Fun Country II Tires, Reverse backup sensors. ARE fiberglass hartop w/airfoil, ITP overboost Kit, BTS valve body, DP-Tuner, Powerslot Rotors/Hawk Lts pads. 6.0 Tranny cooler,Warn Premium Hubs
I think one battery will fill in for the other if one of them is low because they are both connected. Is that correct?
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 Bors
Land Mobile Corporation
99 F350 XLT 4X4 DRW, Knapheide 6132 P-50 Service Body
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
__________________ 2002 7.3 PSD Lariat Crew Cab F-350
AIS intake w/fender mod, ISSPRO 3 guage pillar, MBRP 4" SS exhaust, Bilstien shocks, Dick Cepek Fun Country II Tires, Reverse backup sensors. ARE fiberglass hartop w/airfoil, ITP overboost Kit, BTS valve body, DP-Tuner, Powerslot Rotors/Hawk Lts pads. 6.0 Tranny cooler,Warn Premium Hubs
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
I will agree. The bad battery is like a black hole in space. It will suck the life out of the good battery.
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testing battery/alt
2002 7.3 PSD Lariat Crew Cab F-350
