Quote:
Originally Posted by 30 Closed Cab PU
It is possible you just got a bad battery. It has happened to me in the past on my 12V battery late model cars/trucks.
On new batteries I do not trust the stores, and before use check the level in them to make sure the level is over the plates and then put the battery on a maintained/charger. Some stores simply put the acid in them and do not charge the batteries, this does not fully charge them. The stores rely on your generator/alternator providing a full 1st charge. Recheck the fluid level.
After charging I use this load tester on them, is inexpensive at harbor freight, also available on amazon.
https://www.harborfreight.com/100a-6...ter-61747.html.
I have caught 2 new 12V new batteries bad this way. I also do this procedure on all my batteries in late fall. Started this many years back when in an emergency due to a bad battery when on the road. Towed to a dealer, they installed a new GM Delco battery and tested the charging system for big bucks. 20 months later the battery went dead. They neglected to tell me that their batteries only had a warranty of 18 months.
I would take the battery back and get a new one. Freshen your battery connections, could have corrosion or paint. Install a digital ammeter capable of measuring low current in series with the battery, If you have an digital ammeter with a peak hold feature it will hold the reading of max current measured for display. Turn on the ignition with the points open , do not start it. Let it sit overnight. |
This is good advice.
To which I'll add:
Yes, batteries are not fully charged when initially filled with acid. Add to that a car alternator is a very poor way of charging initially if all you do is drive a few miles. They really need to be on a charger, trickle or otherwise, for a good 24 hours. They should be brought up to 14-14.4 volts for that long a time. A really small trickle charge might not do that. But anything for initial charging is better than nothing.
With really big, really expensive, really important batteries, this is far more relevant. By comparison, car batteries are cheap and most people don't do this, and still get acceptable service life. Any full discharge weakens the battery.
Another really good really easy test method is specific gravity. Get an electrolyte tester, turkey baster style, with a calibrated float, not the 5 colored balls. Test every cell after fully charging overnight. Any low cell condemns the battery. The reading of the weakest cell gives you a very good idea of percent life left in the battery.
Also, check for even electrolyte level, and be aware that after the first full charge cells might need to be topped off. Most battery experts advise to never add acid after this initial leveling, only water. With any modern sealed acid battery, this is moot.
Battery cases are dated now. You have no idea how long they've been on the shelf wet-charged. Look for a recent date.