Battery/Alternator Problems

[6.0DSLPWR]

Hey guys. Now that the temperature is dropping here Ive noticed for the past couple of months that whenever my truck sits for many hours(usually over night) that the truck turns over slow in the morning like the batteries are dead but it has always started.

Then yesterday morning I went to start the truck after sitting all night and it turned over really slow this time and I almost thought it wasn't going to start but it did. I drove around town for maybe 20 minutes then stopped at a store. When I left the store it turned over very slow again and almost didn't start. Clearly my problem got a lot worse yesterday.

So last night I disconnected both batteries and tested the voltage. Each battery was sitting at 12.6. I left them disconnected over night thinking one battery was going bad and taking down the other battery. So this morning I go out side and each battery is sitting at 12.34 after sitting disconnected all night. The batteries in my truck are the original motorcraft ones and I noticed this morning that the sight glass on the pass. battery was showing the red ball while the other one was a green/yellow color. I thought that once the battery showed the red ball it was done and time for a new battery.

Anyway I hooked the batteries back up this morning and tried to start the truck. It wouldn't crank, the starter just clicked and the headlights went out.

Figuring my batteries are done and almost 5 years isn't bad for a set of batteries I went out and bought two new 850CCA batteries and put them in the truck. She turns over crazy fast now.

While starting the truck with the new batteries I hooked my multimeter too one of the batteries. When the glow plugs are on the voltage dropped to 11.4 and while cranking it dropped to 10.8 The truck started right away and the voltage settled at 12.0 with everything off but my radio. I left the multimeter connected to see if the alternator was charging the batteries but after approx 30 seconds the voltage was still at 12.0. It wasn't until I reved the engine up to 1200rpm that the voltage climbed to 13.9 and stayed there.

Oh after pulling the old batteries from the truck I looked at them on the garage floor and the red ball in the pass side battery is now gone and they both are a yellow/green color.

I am starting to worry that maybe my batterys werent the problem and Ive got some other problem. I was wondering what would be the correct way to test my alternator and my old batteries to make sure Ive found the actual problem and not masking it with new batteries. Thanks

[JSchuricht]

Pull your alternator and take it to an Autozone or someplace else that can bench test it.

[banshee42002]

I also have a 05 F350 and been having the same problems....original motorcraft batterys.....I just replaced them today with 2 New Interstate Megatron Plus 850cca and installed a Hi Amp Nations OEM TAD 190amp alt.........Hopefully no more starting problems now.....

[MoyockPowerstroke]

banshee42002...what are you seeing for running volts now? At both start-up and normal driving? Appreciate any feedback. Thanks.

6.0DSLPWER....you most likely jarred loose the hydrometer ball on the one battery (they can flow up and get stuck occasionally)...so your batteries might be okay...but if they were OEM and 5 years old...I would have changed them anyway to avoid potential FICM failure. During the initial start-up (both while waiting for glow-plug symbol to extenguish and for approx 1 minute after start-up) the low voltage is normal due to the fact that your glow-plugs will remain hot (drawing amps) until approx 1 minute has elapsed. 13.9volts is great.

[6.0DSLPWR]

Originally Posted by MoyockPowerstroke

banshee42002...what are you seeing for running volts now? At both start-up and normal driving? Appreciate any feedback. Thanks.

6.0DSLPWER....you most likely jarred loose the hydrometer ball on the one battery (they can flow up and get stuck occasionally)...so your batteries might be okay...but if they were OEM and 5 years old...I would have changed them anyway to avoid potential FICM failure. During the initial start-up (both while waiting for glow-plug symbol to extenguish and for approx 1 minute after start-up) the low voltage is normal due to the fact that your glow-plugs will remain hot (drawing amps) until approx 1 minute has elapsed. 13.9volts is great.

A couple times yesterday and once this morning I started the truck with the multimeter on one of the batteries and everytime I had 12.6 before anything was turned on. When I turned the glowplugs on I dropped to approx 11.2-11.6 each time. Then the lowest I saw while the truck was cranking was 10.6-10.8 then after the truck fires it sits right at 12 volts for maybe 30 seconds then the volatage climbs to 13.9 and stays there. That is with the truck just idling.

So far my truck hasnt turned over slow with the new batteries. But with my old batteries it was turning over slow on and off for the past 2 months. I am thinking my batteries were on there way out since I was looking at them last night and when I pulled the caps off the water is ever cell was a little low. Probably my fault for not checking them sooner but I still think 5 years for a set of batteries is really not that bad at all.

I am going to take my batteries to a battery store this weekend and they will test them for free and I will find out 100% if my batteries are bad or not.

EDIT: I am also thinking it would be smart to get my alternator tested at this battery shop just so I know the condition of it and so I dont end up killing these new batteries.

[MoyockPowerstroke]

Good ideal...keep me posted. Thanks.