Recharging batteries with the engine genny???

All,

I have some 6TL's that are kinda dead, but take a charge.. Almost enough to crank the truck.. If they do crank the truck, will the onboard 60 amp generator charge them, or will bad things happen to my voltage regulator?

Inquring minds want to know.....

Fast answer Yes,and no damage.your truck will just put juice in,if its not taken it won"t be a problem for the truck, It is what its supposed to do, if one cranks the crap out of a bat in cold weather and really runs them down and it starts just before dying, The truck will charge em,and kinda quickly too, a good bat will charge itself if left alone for awhile, to a point, it wants to take a charge... They are for all sound reasons good bats or they would not have taken the punishment, If U are about to take a very long ride, u would do it, But are U sure they will Hold the charge? if U stop and they don"t re start your truck is it worth it, or is the wear and tear and fuel worth charging bats also, They should be brought up to a full charge at a slower amp preferably but not really the most criticle thing in the world, and THEN wait one FULL day to test em, the little ball floats are fine as long as U do it on a rested battery OR U will get a false reading,and also if the ball things are new or dried out ,,not used in a long time , fill em and let em sit for a few minues with the acid...and then use em...checking a resting battery meaning after a full charge has been taken and waiting 24 hours for the battery to rest is the only way one will get a true reading testing any battery... or again U will get a false reading,The desulphaters are the way to go, but the bat has to sit for a minimum of 72 hours for a mostly good bat, and any bat that sits for more than 4 days should be on a maintainer or its life will be shorter than that of a maintained bat, that is when guys say my bats are crap ,they need maintanence too..Hope u do not mind a little more than asked for....Randy

I'm not much for reading long posts, so this may have been covered...If the batteries start out with unequal charges, they won't charge correctly when placed in series, so if you have several batts that are not charged, do them separately with a 12-volt charger.

best to charge them with a bat charger first cuz it puts alot of load on the gen. and good batteries dont charge themselves no matter how long you leave em sit they need to have something with more volts then they have to make the charge .but generally if they will start the truck with a jump you wont hurt anything letting them get charged by the gen .and yes if you run the truck for ten minutes or more it should start right up again if it doesnt you have bad batteries or a generator that's not charging right

I got one of the VDC BatteryMinder Plus chargers. It only puts out 1.3 amps max, and has a lower float voltage than a regular charger, so it can work on AGM batteries. I had a couple of 6TMF's that were really dead (less than 4 volts between the posts). Set the charger on the pulse mode (desulfate) and let it run for about two weeks on each battery, then put the 6 amp charger on for about three hours at a time on each of the batteries (longer on the weekends). Then this past week three days solid on each of the batteries with the BatteryMinder. By the end, each of them had gone automatically onto 'float', and they are holding the charge 24 hours later. YMMV.

emmado22 said:

All,

I have some 6TL's that are kinda dead, but take a charge.. Almost enough to crank the truck.. If they do crank the truck, will the onboard 60 amp generator charge them, or will bad things happen to my voltage regulator?

Inquring minds want to know.....

Click to expand...

If they hold a deep enough charge to crank the truck to start, they should not give your generator any problem, as long as it is in reasonably good working condition. Part of the regulator's everyday job is to limit charging current to a level that won't overheat the generator windings or rectifier packs. When I go out on a long trip into the "boonies" with a 24V vehicle with questionable batteries, I will typically carry along a pair of smallish (well-charged) 12V auto batteries, and 2 sets of jumper cables - just in case the weak batteries need a little help firing off the vehicle. You don't necessarily need another set of 6TL's to get you back on the road - usually just a little boost.

I agree with above posts, the charging system will not be hurt by "bad" batteries, the regulator is current and voltage limited.

About the batteries, though:
They are probably sulfated and may "look" charged when checking the voltage. Get a battery tester (specific gravity) and find out for sure.
If there is little or no change in the specific gravity after a charging period, your batteries are sulfated. If you read some of the de-sulfation device mfg claims, you may be able to regain perhaps 80% of original capacity by using such a device, but it may take a month of continuous treatment....and a good 120VAC powered de-sulfator will cost more than a new set of Walmart batteries.

I need to replace two batteries, I've looked at the farm store and Sam's Club, but having no luck.
Where do you guys recommend buying batteries and what model number?

CharlyArmy said:

I need to replace two batteries, I've looked at the farm store and Sam's Club, but having no luck.
Where do you guys recommend buying batteries and what model number?

Click to expand...

where its cold... get batteries rated for the cold. some recommend commercial batteries that are put into the heavy duty trucks. anyways just pick batteries with High cold cranking amps. and take care of them and they will last a long time.

i hope that helps!

CharlyArmy said:

I need to replace two batteries, I've looked at the farm store and Sam's Club, but having no luck.
Where do you guys recommend buying batteries and what model number?

Click to expand...

I got mine at Napa. Interstate Workaholic U6TL.

They ain't cheap at $189.99 retail but I get them at their cost since I letter all their delivery trucks. They're even OD Green.

Your mileage may vary.

tm america said:

best to charge them with a bat charger first cuz it puts alot of load on the gen. and good batteries dont charge themselves no matter how long you leave em sit they need to have something with more volts then they have to make the charge .but generally if they will start the truck with a jump you wont hurt anything letting them get charged by the gen .and yes if you run the truck for ten minutes or more it should start right up again if it doesnt you have bad batteries or a generator that's not charging right

Click to expand...

A set of good batts that are drained down and will not start a vehicle right after the draw down,"say lights left on." should be left to sit awhile, they can and will activate them selves depending on the quality of the units. hence seem to charge them selves, sorry but this is true....there is also a very dangerous and risky thing to do to a bat that has left one stranded and there is no reasonable way to get a jump, I would never recomend this but i have done it and it can work, again it all depends on the condition of the batts before the discharge and how low they are. it is actually crossing the terminals and heat em up and start her right away, now again i think anyone doing this is stupid me included, but it can and will work like everything else under certain conditions...Randy

6TL's

I just picked up (2) new 6TL's from interstate for $157 each . That is if you bring in your old ones.

BH

ive been working on car- trucks for 20 yrs for a living and i've never seen a battery recharge itself.however i have seen many barreries that were shorted out actually explode .it's usually very violent one knock the grill and head light bucket completely out of a dodge van.another bent the hood up about six inches on an crown vic.if anyone decides to take that advice let me know so i can stand far away when the body farts start flyingas far as lettting them sit to reactivate themselves .you are correct about depends on the condition of the batteries.if you have two batteries inseries and one of them has a dead cell the other one will charge the bad one to even out voltage when sitting.but if you take a battery out and it has 11 volts ten minutes later,a week later or a month later it will have 11 volt or less .but never more without something with more volts charging it.if they charged themselves the wouldnt have generators or altinatorsa battery left sitting on the ground will discharge itself to

It is a short term thing for sure from a recent draw down from a good batt., I am not saying by any means that batts recharge them selves by sitting i did not say that at all., i am saying a freshly drawn down bat that will not turn a vehicle over from a very very recent like imediate draw down can and will raise its level a bit on its own if it is a good batt and it may be enough to get the vehicle running,in this case paitence works. it has and does happen, As for the bad advise if U read it I am saying it is bad advise, But it also can and does work, Yes it is dangerous, but it has worked for me, I have been keeping 6 to 24 batteries alive for over 30 years every year in my fleet, and have had one meltdown so severe, the bat was glowing orange /red on all sides buldging and starting to melt, the truck was over charging, and cooking it, but it was the end of a long day and there were no places to get help, so I pushed it to its limits and beyond, we made to a station where they would not go near it, and right fully so. but i wanted to go home, so i opened the tool trailer got the full face shield gloves and a few extra clothes and removed the cooking bat, i have always been the type to do, I do not mess around, and to be honest if i say something works it is because i have done it. I am surprised U are not aware of a good bet that was just drawn down and left to cool and sit a few minutes may very well have recharged enough to start said vehicle, this is really not voodoo. the bat would have just lost its charge, it wants to stay charged if it is a good sound batt.but as for U saying I am saying a sitting batt will chagre itself, i just did not say that, ...