Optima battery suddenly too weak to crank on 48 DeSoto!

[MarcDeSoto]

 I tried to start the flat head yesterday, but it wouldn't start, even though I had good spark.  I primed the carb. with gas, but I think I flooded the engine.  Now, today the engine won't crank.  I tried to charge the battery, an Optima 6 volt, with my NoCo 10 charger, but it wouldn't take a charge.  The NoCo has a batter repair mode, but just for 12 volt batteries.  I took it to Autozone, and the they said it was dead and wouldn't take a charge. I think I made a mistake when I left the jumper wires connected to the coil all night.  That's like leaving the ign. key one all night.  Now it looks like I'll need to buy a brand new battery!  

[allbizz49]

You tried to charge a 6 volt battery with a 12 volt charger? If so, I'd say that's what smoked your battery, not leaving it hooked up to the coil. 

[kencombs]

A lot of the  newer chargers won't charge a dead battery.  They need to see some voltage in order to work.   Try adding another battery in parallel with the dead one.

 

 

Edit:  or use an older manual charger to get some charge into the totally dead one.

Edited January 1, 2023 by kencombs

[keithb7]

You need a 6V manual charger. Old school transformer type. Hit it with 15A for 30 mins then your digital Noco will charge it. Or just continue charging with the old school manual charger. 

[joecoozie]

Hopefully you did not fry the points by leaving the coil "hot wired" all night . If the points were closed when it was "wired" I think you should check them - and the condenser and the coil.

A friend of mine left the key on in his 48 Chrysler all night, one time, and he fried the coil,points and condenser.

 

[MarcDeSoto]

5 hours ago, allbizz49 said:

You tried to charge a 6 volt battery with a 12 volt charger? If so, I'd say that's what smoked your battery, not leaving it hooked up to the coil. 

I didn't say I charged it with a 12 volt setting.  I said the Repair mode is only in 12 volts.  I do have a regular manual battery charger.  I'll try it.  Thanks.  

[MarcDeSoto]

 

 

5 hours ago, keithb7 said:

You need a 6V manual charger. Old school transformer type. Hit it with 15A for 30 mins then your digital Noco will charge it. Or just continue charging with the old school manual charger. 

I put a regular old, 1980, manual Schauer 6 volt 10 amp battery charger on it for awhile to get it up to snuff.  So I did that, and after a few minutes there was a loud click and the needle went from about 15 amps to 0.  Then after a minute or two it went back on.  and so on.  Is that normal? I guess I should put it on for about a half hour or so, and then switch it over to the NoCo to see if I can charge on the AGM 6v mode.  

Edited January 1, 2023 by MarcDeSoto

[Pete]

Optima has a very specific method on their web site for charging/saving one of their completely discharged batteries. Ask me how I know.

 

Pete

 

 

[Sam Buchanan]

If you do end up needing a battery, you might consider a wet battery instead of the Optima, wet lead acid batteries are more tolerant of abuse. You can find a 6v wet battery at a store that caters to the farm community.

[LeRoy]

I saw somewhere, I think this forum, where someone identified a pretty large 6v lead acid battery for a reasonable price. Can't recall the series number but I told myself that's be my next replacement battery.

[kencombs]

2 hours ago, MarcDeSoto said:

 

 

I put a regular old, 1980, manual Schauer 6 volt 10 amp battery charger on it for awhile to get it up to snuff.  So I did that, and after a few minutes there was a loud click and the needle went from about 15 amps to 0.  Then after a minute or two it went back on.  and so on.  Is that normal? I guess I should put it on for about a half hour or so, and then switch it over to the NoCo to see if I can charge on the AGM 6v mode.  

Sounds like the old charger has an internal auto-reset breaker.

[joecoozie]

NAPA and Tractor supply sells the BC1 6 volt batteries.

NAPA price is $123-$135

Tractor Supply price is $120

[keithb7]

I have no idea or experience with Optima batteries. Flooded wet cell battery, I’d  try turning the old battery charger amps down. Try 6V 2A. For a few hours. The see if it’ll take that charge. 

[Los_Control]

I just find it amazing that a modern battery charger will not charge a dead battery .... Who thought that one up?

 

I love my old stuff all the way, that includes old school battery chargers.

[keithb7]

@Los_ControlI agree. Digital battery chargers seems to have created more problems than the old ones. I have full control with my 6V 15V charger. I turn it on, full manual mode, then set an alarm on my phone for an hour or so later. It takes some thought and common sense. Yet I can control the charge rate. I prefer that. 

[chris 48 P15]

i just bought a shumacher sp 1296 trickle charger does everything automatically 

6 or 12 volt only 2 amp 

very nice

don't know if it will work with optima battery there is info on that on the optima website

question

if i connect to car can i leave battery connected to car or should i disconnect

[Los_Control]

That is true @keithb7 We use a battery charger to charge dead batteries.

If the charger will not work because the battery is dead .... ????

 

Lots of amusement in today's world.

[allbizz49]

Optimas aren't of the same quality as when they were being made here. Can't beat a good ol wet cell 6v. Also, can't beat old battery chargers. This has been the best 10 bucks I've ever spent at a swap meet.

[LeRoy]

I recently got a do everything harbor freight 4 amp charger. No idea if it will work but it claims it can save/restore completely dead batteries. My money is that's total marketing bs.

[DakotaFrank]

I have a Schumacher 6v/12v 2A/6A charger I bought about 33 years ago.  It is completely manual.  Last time I used it worked great. 

[MarcDeSoto]

I've been using my old 6 volt Schauer charger.  It has some kind of circuit breaker inside that shuts off the power for a few minutes, then turns it back on.  It's a 10 amp charger and you can't set it at a lower amperage.  The needle was pegging for awhile past 15 amps, and now it is charging at about 12 amps.  I bought a battery tester at HF today and tested the Optima.  When I turned on the toggle switch for 5 seconds, the voltage read about 5.9 volts.  The NoCo charger still won't charge, so I'm leaving the old charger on a bit more.  I read that the voltage needs to get up to 6.1 in order for the NoCo to work.  

[Los_Control]

Just now, DakotaFrank said:

I have a Schumacher 6v/12v 2A/6A charger I bought about 33 years ago.  It is completely manual.  Last time I used it worked great. 

I have basically the same Shumaker charger but only 6 years old ... works fine.

[Plymouthy Adams]

1 hour ago, LeRoy said:

I recently got a do everything harbor freight 4 amp charger. No idea if it will work but it claims it can save/restore completely dead batteries. My money is that's total marketing bs.

yessir....buy one of them and never buy another battery for the rest of your life...you likely will never be leaving home either.....

[Marcel Backs]

Best thing for any battery is a slow charge. My old Marquette booster/charger mostly gathers dust since I find the new low current chargers are not harsh on your now very expensive battery. In my opinion, AGM batteries are the way to go, hands down! The important thing with any battery, is to charge it at low current at regular intervals during storage (not so important if your climate allows year round use of your vehicle). A battery which has been totally discharged will never be the same, even if left in such a state for a short amount of time. Optima batteries are very sensitive to this situation. Their reliability has room for improvement since they only last 5 or 6 years which is the rate my 39 Chevvy consumes them. I am presently researching the Lifeline GPL-4CT 6 volt AGM for the D-14. It is used in marine and RV applications, Mil rated and most of all made in the USA. A battery is never a component to cheap out on and is really a component that drives the "you get what you pay for" saying home. M

[RedRam]

The reason modern chargers won't charge a completely discharged battery is to prevent the possibility of the battery being charged backwards causing the positive/negative posts to be backwards. The new chargers check your connections and will tell you if they are backwards and won't start the charge. If there is no charge in the battery, it can't tell if it is correct. The default programing, then, is to not provide a charge.

 

Paralleling another battery (positive to positive, negative to negative) will trick the charger into providing a charge. This doesn't have to be done for very long.