Mq Patrol battery readings

[79raven]

Hey guys, got the shorty today. The bloke said the batteries were dead from sitting for a while and would charge when I drove it. When driving it the gauge was reading around 24 volts in the car, but when I got it home it wouldnt start again. I checked each battery with a multimeter and one was reading 10 volts and the other 12.7. I chucked the 10v battery on the charger in the garage and read on the net they are suppose to be 12.6v when charged, so at 12.7 I took the battery off the charger and put it in the car. got closer to starting but still nothing.
whats a single N700ZZ battery suppose to read volts wise? I ask because maybe I didnt charge it long enough
Cheers
Rob

[Cuppa]

Charge it until it gets to around 14.4v, take it off charge & leave it for an half an hour or so before checking it's voltage. If after that time it is reading better than 12.6v it is probably ok. To be sure, connect a load, a 60w headlight globe would do, to the terminals for 5minutes or so. Disconnect & let the battery stand for a while, 10 minutes is probably ok & then check voltage again. If it is still 12.5v + the battery is good. If not it is either stuffed or on the way out.

I'm no electrician, so someone like Yendor may come along & refine what I've said, but taking it off charge as soon as it reached 12.7 was premature.

Cuppa

[79raven]

Cheers thanks for that. Ill wack one on all night and see how she goes in the morning. She wanted to start at 12.6 volts but just kept clicking ( better than the nothing before). The bloke said the car had sat for 12 months so they probably are in need of a charge and the Alt would have done sweet fa due to the crap terminal connections ( loose).

[threedogs]

You have given what is called a surface charge leave it on charge .What stlye Battery is it Wet cell AGM, etc???

[Cuppa]

There is a pretty good chance that if it sat uncharged for 12 months it's stuffed. I would suggest that as well as keeping your fingers crossed ;) that you charge each of the two batteries & check them out as I suggested. Ensure before doing so that the plates are well covered with electrolyte, if not top up with distilled water before charging. Clean terminals before refitting.

[79raven]

The batteries are both BBS extreme ( never heard of them) N70ZZ's. Both look almost new and fluid levels were good. From what I understand about what the bloke said was he did all this work on the car ( maybe batteries aswell?) and never got a chance to drive it. It sat finished at his old mans place because his Mrs wanted him to spend his time at home and not in the bush. Weather thats crap or not time will tell. Im going to change the terminals for both batteries and clear some new wires as they arent 100%, thats why I think the alt didnt charge them while I was driving. Like stated, fingers crossed because my $950 bargains going to look not so good if I have to spend $400 on 2 new batteries. Thanks guys.

[GQ TANK]

If one battery is faulty - you will need to replace both

[Yendor]

When you get the vehicle running you will need to confirm with your multimeter that the alternator is charging the batteries.

Also make sure that a 12 volt accessory hasn't been connected to one battery, this is the quickest way of killing batteries in a 24 volt system.

Cuppa battery test will give you a good idea of the condition of the batteries.

Most battery suppliers or auto electricians will also be able to load test your charged batteries.