Can an Optima 6 battery come back from the dead?

[marcapra]

Last summer, I bought an Optima 6 battery.  It cranks the engine over nicely.  But I was trying to start the engine for the first time yesterday, and it wouldn't start because of flooding the carburetor, I think.  I left the jumper wires connected to the coil all night, so I think that drained the battery.  Now the battery won't charge because it's too dead.  Is there a way to repair the battery so it will charge again?  There is a repair mode on my NoCo Genius 10 charger, but it's only for 12 volt batteries.  

[Matt Harwood]

Connect it to another battery, then connect the charger to that battery. Some chargers can't "talk" to the Optimas.

[37_Roadmaster_C]

What Matt said ^^^^^.  Matt was not specific, but use another 6 volt battery for the nurse battery. Charge both until charged, then disconnect the nurse battery and reconnect the Optima and charge again on low current until charged.  Chanced are that the Optima is slightly damaged, but they have the ability to survive much better than regular lead acid batteries.

[marcapra]

Can that nurse battery be just a regular lead acid 6 volt battery?  And do I charge them in regular 6 mode, or AGM 6 mode?  

[Grimy]

1 hour ago, marcapra said:

Can that nurse battery be just a regular lead acid 6 volt battery?  And do I charge them in regular 6 mode, or AGM 6 mode?  

Yes, a wet 6V battery is fine as the nurse.  I can't answer your second question.  For the future, try to avoid getting an Optima below 6.0V.

[Hans1965]

My chargers consider a very low battery as dead and therefore don't charge as a safety precaution. If you follow the already described procedure, after already 2 h the low battery has enough juice to be recognized as chargeable. Then you can switch to the agm charger and charge the optima only. I think it doesn't matter if the nurse battery is agm or a normal battery. You need it only a limited time. 

[marcapra]

Looks like anyway you slice it, I have to buy another battery.  I should never have left the jumper wires to the coil on overnight!  

[marcapra]

I was told I could put a regular old manual 6 volt 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?    

Edited January 1, 2023 by marcapra (see edit history)

[alsancle]

Modern chargers will not charge a completely dead optima. The battery may still be fine.

 

By attaching a semi charged or fully charged battery at the  same time it will trick the charger.

[Ben Bruce aka First Born]

I do not own an AGM battery. So I have a question.  Would connection  jumper cables from the battery in another car, leaving second car running, work.?

 

  Ben

[marcapra]

Maybe?  But I don't have anyone near me with a 6 volt car.  I ran my old battery charger on it for 30 mins.  It cycled on and off every couple of minutes.  Then I put it back on the NoCo.  No dice.  Maybe I have to put it on the old charger a bit longer?  

[Bloo]

It may just be toast. There is a good chance of it. Running a lead-acid battery too dead damages it. Leaving it dead does it in. On the third day dead, I would say there isn't really much hope, but I would still try. It doesn't really matter if it is an Optima or not. I'd put it on a conventional charger and hope for the best. I don't know what would be clicking in the charger. It sounds like it might not be a completely conventional charger.

 

I think these modern "smart" chargers are a pox on the antique auto hobby because they make you waste time screwing around just trying to get them to turn on and do something. Meanwhile, the chances of saving the battery, or even bringing it back to a semi-usable state sail away.

 

Modern charging modes are useful and do have their place, but if you are going to have only one battery charger, conventional and OLD is where it's at. Get something like the random internet example below. Every suburban house in the US had something like this in the garage from the 50s to the 90s or so. There are probably at least 30 brands, one of the most common being "Sears". The surplus now must be massive because everyone has "upgraded" to a smart charger. Look for about 6-10 amps, a 6-12 volt switch on the front panel, and an ammeter. Get one that's too old to have any fancy electronics inside. Should cost about $5 at a yard sale.

 

 

 

 

 

[jp1gt]

I take care of at least 30 batteries in cars, carts and equipment. I do not buy anything that I can not see the electrolite level anymore. If you can not test the cells you are flying blind. You can add water to optimas but it is very time consuming. You can always get a large battery that does not have electronics to charge if there is not a bad internal problem. The battery companies are cutting corners and longevity is suffering. There are many things that work but it never has a pattern. Using an old charger is a good start. the damn cordless tool electronic batteries are a different story. My experience and opinion----

[60FlatTop]

After I bought my smart battery charger I bought a nice soft set of short jumper cables to put next to the charging area just to hook up batteries in parallel just so the charger would see them.

 

When they are really flat I use the old charger to get enough juice in for the charger to recognize, then bring them up slow with a tender.

[junkyardjeff]

I have found modern chargers have a hard time charging dead batteries,the body shop I worked at had all modern chargers so I had to bring iny old school charger to charge up a couple dead ones.

[rocketraider]

 

😍🥰

 

I have a Black & Decker smart charger that works ok, but I have more fun with my old (80s) Sears and especially my 70s Schumacher. They're both automatic shutoff and hydrometer tests prove that when they shut off, the battery is fully charged.

 

The magic of those old chargers like the above Sears is they're simple, there's not much to go wrong, and they get the job done while a smart charger is futzing around trying to decide if a battery will take a charge.

 

Besides, charging at 2-5 amps for a couple of hours will usually bring a serviceable battery back enough to start an engine.

[Frank DuVal]

12 hours ago, Grimy said:

For the future, try to avoid getting an Optima below 6.0V.

True, but also important is for the future to get an old fashioned charger that will put out volts with an open circuit! Use it to bring dead batteries back, then finish the charge with the modern charger.

Edited January 1, 2023 by Frank DuVal (see edit history)

[joe_padavano]

My open loop "dumb" charger that I got in the early 1970s still works better than the "smart" charger that I have.

[Grimy]

19 minutes ago, Frank DuVal said:

True, but also important is for the future to get an old fashioned charger that will put out volts with an open circuit! Use it to bring dead batteries back, then finish the charge with the modern charger.

Frank, I've been using Optima 6V batteries exclusively for over 20 years, and have had about 60%-70% success in bringing back deeply discharged ones.  I quickly abandoned modern "smart" chargers if the battery is below 6.0V, which I've subsequently refined to 6.1V.  I have had very limited success in using 1950s/1960s "dumb" chargers (I have four) by themselves (i.e., without a nurse battery) on deeply discharged Optima 6Vs.  The use of a nurse battery with a "dumb" charger until the discharged Optima reaches about 6.1V is the technique that has worked best for me.  At 6.1V on the discharged Optima, I now remove the nurse battery and use a "smart" charger on the Optima.

 

I'm always happy to hear of alternative techniques that might improve upon the  60%-70% success rate.

[Buffalowed Bill]

All three of my old chargers are old enough that they each will do a good job of charging my Optimas. I'm sure many of you have an old bat. charger lying around that should work.

[Frank DuVal]

Interesting, the nurse battery supplies a more constant DC current (less ripple) to charge the Optima vs the half or full wave DC waveform of the simple charger. Maybe the Optima likes pure DC?  Also the nurse battery is charging the Optima even without the charger working, just a lower current than the charger supplies typically.

[marcapra]

I finally charged up my Optima 6 battery using my old Schauer battery charger.  I kept trying to let the NoCo charger take over, but it would only charge for five minutes and shut off.  So I kept charging with the Schauer and the amperage kept going down as the voltage on battery kept going up.  Finally, my battery reads 6.5 volts on my new Centech battery load tester that I bought at HF today for just $15!  Then I hooked up the jumper wires to the coil and cranked the engine over to test for spark.  I have spark, so I didn't fry my coil, points and condenser!  My friend says to buy some starter spray to induce starting, so I'll try that tomorrow.  

[Frank DuVal]

NO! Do not use starting fluid. If a downdraft carburetor, just remove the air cleaner and put a capful of gasoline into the venturi, replace the air cleaner and start the car. Updraft is more of an issue, since you cannot pour the capful of gas in it.

 

Starting fluid in very small sprays may be not damaging to internal parts, but the tendency is for people to spay for a second or two and load the intake so the pre-ignition causes internal damage to very expensive parts.  Just saying....

[Fordy]

I had one that was completely discharged as a result of leaving a light on. It would not take any charge using the "C-Tech" maintenance charger that I have so I gave up on it as dead. 3 years later I am about to scrap it and since there is nothing to lose I try an experiment. What I did was series up the dead one with a good unit and put that on a 12V charger (2 x 6V in series _12V) 24 hours later I check and I have 3 V showing on the "Dead" battery. I then put that one onto the 6V maintenance charger and it was showing a full charge a little over 24 hours later. That "Dead" battery has been going strong in a car now for over 2 years.

[Ben Bruce aka First Born]

7 hours ago, Frank DuVal said:

NO! Do not use starting fluid. If a downdraft carburetor, just remove the air cleaner and put a capful of gasoline into the venturi, replace the air cleaner and start the car. Updraft is more of an issue, since you cannot pour the capful of gas in it.

 

Starting fluid in very small sprays may be not damaging to internal parts, but the tendency is for people to spay for a second or two and load the intake so the pre-ignition causes internal damage to very expensive parts.  Just saying....

 

 OH CRAP.  Does that mean I have been doing something WRONG for the past 70 years?  😉.I guess I should go back and apologize to all those hard starting SOB's of my past.

 

  Ben

[Frank DuVal]

No, Ben, you probably use it correctly!

 

I see stuff broken, especially in the small engine world.

 

Or the people who hold the spray in their hands while a helper cranks the engine, backfire, and the resultant human damage....