New Battery Won't Take Charge

[Bingster]

I bought a new battery a couple of weeks ago for a first start of my '47 DeSoto. It didn't start and we only used a fair amount of power attempting it, and now the battery doesn't seem to take a charge.  We've had it on a trickle charger for a good three days and no luck. The charger is supposed to fully re-charge the battery?  ??

[Plymouthy Adams]

is this a so called 'smart' charger failing to turn on because the threshold voltage of the battery reserve is too low?  See if you can parallel it with another good battery if it will turn on the charger if this is the case.

[plymouthcranbrook]

New batteries can be bad out of the box. I had this happen with a Farm and Fleet battery a few years ago.  Try an older model “dumb” charger if you have access to one as they don’t care what the starting level of the battery is.  Have you tried jump starting the car?

[Sam Buchanan]

Disconnect the trickle charger and find an old-school dumb charger and use it for 3-4 hours. That will bring voltage up enough for the smart trickle charger to engage. 

[Sniper]

 it could be a bad charger? I had that happen to my lawn mower battery. It was low I put my charger on it let it charge overnight still didn't work so I grabbed my other charger put it on in less than an hour it I had a running mower

[Bingster]

I'm taking it back to O'Rielly's.  They said they'd check it out. Since the market for 6v auto batteries are rare, it could have been sitting on a shelf for a long time. The trickle charger is a Genius 1. They seem to have a good reputation, but . . .

[Joxster71]

All batteries have a date of manufacture on them and sometimes they sit on the auto parts shelves for awhile.     I won't buy a battery if it is more than 6 months old.....There is an autoparts store here that will order batteries for you that are guaranteed brand new.     You can see if your stores will order you one.      I prefer optimas myself.

 

[soth122003]

Your in Iowa which is a farming state. You might try a Tractor Supply as their 6v battery turnover is higher and the batteries don't sit on the shelf for a long time. I went to AutoZone one time and the newest 6v battery had a manufacture sticker date of over 10 months old. The oldest was about 15 months.

 

Joe Lee

[Bingster]

My battery is labeled March 23.  On the cusp.  I'll try to get a new one.

[Sam Buchanan]

No need to be hasty. The 6v battery in my P15 is four years old and still in great health. But it has an alternator sending it rated voltage at all times to maintain its full charge. However, it sat unused for a year before I purchased the car and still returned to a healthy state of charge. Many "battery problems" can be traced to poor charging system performance and sketchy wiring.

Edited October 4, 2023 by Sam Buchanan

[Los_Control]

I know with a 12 volt battery you can go to almost any auto parts store & they have a battery tester they will bring out to the parking lot and test your battery.

I like these because they also load test them, not just measure the amount of charge they have in them.

 

Do these work on a 6 volt battery? .... I have no idea.

 

Also as others suggested, it could be the charger is not working .... have you tried it on other batteries?

[Bingster]

By the way, what is this alternator adaptation all about.  Price to convert?

[soth122003]

I just did mine. It was about $200. It comes with the universal mount, so once assembled just install and go. I've had 2 genny's go bad in the past ten years. 

 

https://www.ebay.com/str/HowardEnt?_trksid=p2047675.l2563

 

Joe Lee

[Bingster]

That sounds like a good idea. I think my genny is shot.

[D35 Torpedo]

1 hour ago, soth122003 said:

I just did mine. It was about $200. It comes with the universal mount, so once assembled just install and go. I've had 2 genny's go bad in the past ten years. 

 

https://www.ebay.com/str/HowardEnt?_trksid=p2047675.l2563

 

Joe Lee

Genny's don't really "go bad" unless there is a major malfunction. Brushes wear, bearings wear. It really comes down to the voltage regulator. It will burn up a genny or under-charge a battery. I've seen many instances of people going through multiple alternators as well. It's just the nature of the beast.

[Kilgore47]

If you go with an alternator make sure you get the correct pully for the wide belt on your car.  

[Bingster]

O'Reilly's has tested the battery and said it was good.

[soth122003]

On 10/5/2023 at 12:22 AM, D35 Torpedo said:

Genny's don't really "go bad" unless there is a major malfunction.

Mine in both cases were the armature (but they were both about 50-70 years old). One of the problems is trying to find the right armature. I ran the armature number and came up empty. A shop to rebuild it may have an inside that I don't know of, but the price to rebuild the first one was $85 and that was about 10 years ago. Slatgrill in the topic Testing/adjusting amperage output, said his repair would be about $125. Since this is my second time with this and prices have gone up  (genny and VR maybe) and repair shops have gone down, that cost would exceed the $200 I spent on the alternator and mount so I went with the alternator. Later I will have the genny rebuilt for originality to the car.

 

The other thing I like about this company and the alternator is that they are in and made in the USA. Unlike the cheap chinese knock offs that don't care about reputation as much as mass sales, this company and products are reasonably priced and readily available. If the alternator does go bad outside of the warranty the price is acceptable and it is an up to date product. Plus there is no maintenance on the alternator, unlike the genny that requires brushes, cleaning the commutator and lube of the bearings and shaft periodically. (Since I can't remember what I had for breakfast yesterday let alone the last time I gassed up the Plymouth, trying to remember when I am supposed to do periodic maintenance is problematic).

 

Joe Lee

[Sniper]

I test batteries for a living, well I do other things too but that's one of the things I do.

 

Do you have a meter?  If so get me the following readings.

 

With the battery not connected, what is the voltage on the battery terminals? (this is to see if the battery is fully charged)

 

With the battery connected, but nothing turned on in the car, what is the voltage on the battery terminals?  (looking for a drain in the electrical system)

 

With the engine not running and the headlights on, what is the voltage on the battery terminals? (load test of the battery, light load)

 

With the engine running and nothing else turned on, what is the voltage on the battery terminals?  (checking the charging system)

 

With the engine running and the headlights on, what is the voltage on the battery terminals? (checking the charging system with more load)

 

With the engine OFF and the ignition disabled, crank the engine over, what is the voltage on the battery terminals? (maximum load test on the battery)

 

 

When using a charger to charge the battery the charging voltage has to be above 6.44V, so you can hook your charger to the battery and measure that as well. 

 

Edited October 6, 2023 by Sniper