Battery behavior

[Agnem]

Here's a weird thing that's got me wishing I was a battery expert. Last April (04), the batteries in the Moose Truck were getting tired or so it seemed. They were only 1 year old. No matter how long I charged them, they just didn't seem to want to take a full charge, so I turned them in under warranty. Interstate took them, and charged them up, and said they were good, and kicked them back to me. In the meantime, I had put in a new pair that made the Moose Truck happy all over again. I took the old batteries that were rejected as being bad, and stuck them in the boat. Used them all summer. Then last winter, the Lady Moose needed a pair, and they were out of the boat in storage, so I threw them in her. She's been real happy with them. Now, here it is a year later, and I'm seeing the same sorid tale repeat itself. The Moose Truck is unhappy with his batteries, and I've got the charger on them, and they just don't seem to take. I put the charger on, and they draw about 8 amps, and slowly reach the full charge level. If I disconnect the charger for 30 seconds or so, and reconnect, it goes right back to 8 amps and starts the charging process all over which lasts a few minutes, and then it's charged again. I know the truck is charging when it's running, cause I've got a volt meter to watch. But at idle, they seem to draw more than what the Moose's alternator can put out. This is really baffling me. Right now, I have them on a 1.5 amp trickle charger that is warm and doesn't give any sign of reaching the "float voltage" stage. I can't figure if I've got a bad battery charger, a bad battery, or what. Keep in mind that these batteries DO sit an awful lot, and I have not put a battery maintainer on them until now.

 

[tuckerd1]

Get a load tester and check the batteries.

Also sounds as if you may have an issue with the Moose alternator at low rpm. What is your voltage output at the battery with a good multimeter?

Don

 

[Max Power]

That actually doesn't sound out of the ordinary for batteries. What exactly makes you think that there is something wrong with them? Slow cranking or something? If you are going on the charge they take from a battery charger that doesn't really tell you much IMO. I am pretty certain a brand new lead acid battery will do the exact same thing you described.

 

[F350camper]

Id say the Moose has an issue with his charging ckt. (Alt or regulator). Or even a v-belt with a big ole chunk missing.

I'd fire him up and let him idle, and turn on the headlights. Then, I’d watch my voltage right at the battery. If goes something like 13.2 …. 13.3 … 13.4 … 13.5… etc then I’d go back to scratching my head.


But on the other hand, if it goes 12.7 … 12.6…. 12.5 … 12.4… Id start shopping for a new alt or voltage reg.

 

[Agnem]

If goes something like 13.2 …. 13.3 … 13.4 … 13.5… etc then I’d go back to scratching my head.

That's what it does. The problem is, if it sits for a week, the batteries will be virtually dead. I've already checked that I don't have an excessive parasitic load when the truck is shut down. I'm wondering if I have sulfification or a shorted cell in one of them. Might have to isolate them to see where it goes next.

 

[F350camper]

...The problem is, if it sits for a week, the batteries will be virtually dead....

In the voice of Yoda,

“Hmmm, reason for problem you have discovered. Drive that truck you must, or be overcome by the darkside you will. Don’t underestimate voltage sucking power the darkside has”

On a Serious note though isolating them sounds like a good plan. Charge-em both up and leave them both disconnected for a week and see who the winner is. Or disconnect one at a time.

Still could be the voltage regulator though. It could be that it isn’t properly “disarming” the alt when the key is shut off.

 

[argve]

That's what it does. The problem is, if it sits for a week, the batteries will be virtually dead. I've already checked that I don't have an excessive parasitic load when the truck is shut down. I'm wondering if I have sulfification or a shorted cell in one of them. Might have to isolate them to see where it goes next.

Not to be a butthead but I must ask how did you check? Did you throw an amp meter on the main line headed into the truck circuit? If so what was the amp draw? Don't have to down to the micro amps but a ball park will tell us if you got a sneak circuit... I know when The E was eating batts over a couple of days - she was pulling just a shade over 1 amp. Does anything feel warm when you pop his hood (after sitting overnight) like the ALT for example...

 

[Agnem]

I disconnected both negative cables, and connected an amp meter between one cable and one battery negative post. It showed about 100 milliamps, which would be about right for the security system and radios. So much for my clock and favorite radio stations.

 

[93turbo_animal]

I disconnected both negative cables, and connected an amp meter between one cable and one battery negative post. It showed about 100 milliamps, which would be about right for the security system and radios. So much for my clock and favorite radio stations.

I'm suprised that for as much as the moose truck sits that you don't have a battery disconnect you never know when a mouse could short out some wires and **** fire ball but it kinda sounds like your batts are getting a build up between the plates and draining them selves you might want to take them out and drop them on the floor a couple times from a few inches off the ground to clean the plates

 

[tuckerd1]

I'm suprised that for as much as the moose truck sits that you don't have a battery disconnect you never know when a mouse could short out some wires and **** fire ball but it kinda sounds like your batts are getting a build up between the plates and draining them selves you might want to take them out and drop them on the floor a couple times from a few inches off the ground to clean the plates

Have you done this with success. Seems to me the sulfate and other stuff would builup at the bottom of the battery and short out plates.

 

[budtoh3zo]

Try putting it on a bigger battery charger. Sometimes if u put enough current threw them it cleans them good. Thats what we have to do on some of the tractors that sit all summer.

 

[Agnem]

Try putting it on a bigger battery charger. Sometimes if u put enough current threw them it cleans them good. Thats what we have to do on some of the tractors that sit all summer.

That's kind of what I'm thinking.Read This

I think this describes my problem exactly, even down to the 1 year time frame. Guess I need a desulfication device.

 

[towcat]

Hmmmm.....interesting reading. I've always figured trickle chargers were all the same. Been fighting with my batteries for years. always figured that the vibration and bouncing killed them. That may have been partially true.

 

[Agnem]

I'm not having much luck finding a local source for these devices, yet alone somebody who knows what I'm talking about. Guess I'll have to pick one and mail order it, but I need to find out which ones if any will handle a pair of batteries at once.

 

[tuckerd1]

I'm not having much luck finding a local source for these devices, yet alone somebody who knows what I'm talking about. Guess I'll have to pick one and mail order it, but I need to find out which ones if any will handle a pair of batteries at once.

Is this what you want Mel?

Battery Desulfator

EDIT: Sorry, just reread your post and you wanted local source.

Don