Am I doing this wrong??

[colbystephens]

Grrr. So my batteries are dead. I put them on the trickle charger over night, connecting them by jumper cables while I had the charger on the one. Didn't seem charged this morning when I put them back in the truck. I put them back on the charger (same way) and tried again tonight - a little better, but not enough to spin the engine over. So I just put one alone on the charger.

Charger says they're full, but I don't believe that thing's meter too well.

Is it not workable to put them both on the same charger? This is dumb.

 

[tRustyK5]

How is everything else? Bad cables can create the impression of a poor batt. I have charged the batts in my diesel pick-up in the truck and fully connected. Both batts take the charge.

Rene

 

[Fordum]

Got a voltmeter? Two things to check.
First, measure the voltage of the charger clamps while it is charging. Should be about 14.5 if charging meter is not showing amp draw.
If not, charger is bad or charger wire is bad.
If they are top post batteries, measure at the post its self, not the clamp and see if the 14.5 is at the post.
And/or, try this. Turn the charger off, measure at the post. Should be over 12 right after.
If so, turn on your headlights, fan on high.
Put the meter from the battery post to the clamp on the same post on each terminal. Should read 0 volts. If you read over about .1 volts, you have a bad connection.

If they are side terminal, just go ahead and take each cable off and clean the connection just in case.

BTW, by hooking them both in parallel like that, it will take twice as long to charge both as it does to charge one, and a trickle charger might take a heck of a long time to do it.
But, the charger amp meter should show charging.

 

[bailey9r]

I think it would take a week to charge a dead diesel battery with a trickle charger. when charging two are you in series or parallel? Mine has two 1000 amp Batts and at just a couple of amp hours it would take a long long time to top them off, although it is better for the battery charging slow than fast. Just my two cents worth (and your prolly wanting some change back)

 

[MJB774X]

these are invaluable tools in my opinion...saves a lot of headache

 

[4X4HIGH]

Colby, you might have a bad cell in one or both of the batteries. You can have a fully charged battery that has a bad cell and it will act like it is dead because you don't have the cranking amps because of the dead cell. You need to get a carbon pile load tester on the battery after it has been on a slow trickle charge for 24 hours but don't pull it off the charger and do the load test right away, give the battery some time to cool down from the charge (maybe an hour or so).