OK. Fine, I'm an idiot. I'll take that. Now for my moronic question...

So I bought this 72 350 Vette from a guy who replaced the battery back in, get this... 1998... with an AC Delco battery and a green round spinning kill switch. It works fine still and fires right up. But, this clearly defies reality and makes me nervous, so I want to replace this thing. Stick with AC Delco? Any particular model? What about jumping when needed... I heard bats with side -and- top terminals is a good idea. Any suggestions?

 

Batteries are a tough subject for a lot of folks. I studied them for many years as part of my job and I have seen several factories and know some of their tricks. If your Corvette has actually been able to get 25 years out of a replacement battery that is a "first" in my book. When batteries are made they used to ship "dry charged" and the battery didn't really start to wear until you opened it up and filled it with the electrolyte. Once the electrolyte is put into a battery the plates will start to shed their lead and this is what frequently determines how long it will last. The C3 Corvettes all came with Flooded Lead Acid batteries in them and most of them use Antimony in the lead plates to make them harder and last longer. The bad side is that the Antimony is a poison to a FLA battery and the amount of Antimony determines the life expectancy. In Europe they use Selenium which hardens the plates like the Antimony but is more expensive. Lead Selenium plates do have a much longer life than the standard Lead Antimony plates used in the United States.

IF your car was able to get 25 years of life from a AC Delco battery then I would buy another AC Delco just like the one in the car now. Me personally I have had great experience with Interstate Batteries but that is a personal choice. I have used EverReady Car batteries and had them last 6 months or less. I have had poor experiences with Walmart batteries as well.

When buying a battery ignore the warranty that they offer as it is a gimmick to get you to buy another of the same brand and type when the battery fails. I have seen companies sell the same product with a longer warranty for more. They just charge more and force you to buy another from them.

I take a look at the case and see the date when the battery was made, usually I will buy the newest or freshest battery. I also take a Multi-meter to ensure it is fully charged. Buy your battery someplace that sells a lot of batteries, some places have them for months on the shelf and they don't recharge them and this can lead to a reduction in capacity.

Before you use the new battery charge it to 15 Vdc before putting it in the car. This helps you start off on a good solid charge. Many cars do not fully charge the battery while driving.

I personally like the batteries that have both side terminals and top posts. I recently added a EFI system and use the top posts to power the EFI system. It is certainly convenient to have the extra terminals, especially when jumping the car.

The little switch that isolates the battery from the car is a good thing to have as well. Modern electronics are not always happy to have the power connected and disconnected briefly while tightening the switch down. I used a Marine Circuit Breaker rated for my full alternator output plus 50 amps.

Get a battery charger that is rated anywhere from 10 amps on up and that will effectively charge the battery up to the point of gassing (15 Vdc) to ensure that the electrolyte is not stratified.

I pull my batteries at the end of the season and then bring them into my garage where they are charged on a timer versus using a battery Tender. It gives me an excuse to check the electrolyte level and add distilled water (if needed) and then clean the top of the case and the terminals as well. Most FLA Batteries have vents and require electrolyte top offs. The water is what boils off so you only add distilled water to replenish the fluid level inside the cells. In the older days they had six little screw on caps for the individual cells. Today two caps that each cover three cells is more common. I always buy a FLA that lets me access the electrolyte

After you get your new battery in your Corvette be sure to measure the battery voltage from the starter positive post and using the engine block as a ground. This will ensure that you have good solid clean connections between your battery and the engine.

Good Luck!

 

Tim -- I installed Dual Terminal (DT) AC Delco batteries in my C3's because it is easy to hook up jumper cables or a battery maintainer to the top posts. Hooking up jumper cables to side terminal bolts usually results in bolt heads that get messed up, or a lousy connection when you try to jump the car.

AC Delco makes a 75 series and a 78 series DT battery. Select the one that suits your needs. They have a convenient handle that folds flat out of the way. This pic is of a 78 series.


I put these DT batteries in all of my other vehicles as well. They last about 4-6 years depending on the vehicle and the usage.

 

I have a 3 year warranty walmart battery in my vette now that has lasted 13 years so far.
I just put a tender on it when I'm not driving it.
Forget about the brand on the outside. Most are made by Johnson controls. So you can pay more, or less for a battery and the difference may actually only be the warranty offered and the label.

 

acdelco bats were very good.
a good volt reg will prolong bat life or burn em up.
I use acdelco bats and they pretty much get what they are rated for. a 7 year would get 7 years opposed to getting far past the rating in years past.

I also use dual post for convenience.

people have their favorite brand like oil and tires.

 

Thanks all. Would a 75 or 78 be better for a 72 350 base engine 4 speed that generally lives in the garage all winter and gets a few hundred miles in the summer?

 

the bigger one, physically

 

I have had my 2019 walmart "branded" battery get run down to dead twice now... Once due to a faulty rectifier and once due to a dome light left on... The last time I had no lights at all. I thought it was a goner for sure when my smart charger stated it was "shorted or sulfated" but after charging in "desulfate mode" I put it on my load tester and believe it or not it still passed and has been working fine for the last month since. I do carry a small lithium battery jump box in case it ever does fail me.

 

a battery tender of some kind is the most ideal for this.. Normally I do this but this year I skipped it and in an unrelated coincidence I had a dead battery or so I thought.

 

Recommend a 78 and a smart charger for the winter. I use Interstate battery and a Deltran charger.

 

I recently replaced the battery in my '08 and learned a few things. Should all apply to a c3 also.
Napa does not honor their pro rated warranty on their 2 1/2 yr old batteries. Total crooks.
Most new batteries have either a 2 yr or 3 yr warranty, not pro rated 5 yr warranty anymore.
The AC Delco from the local Chevy dealer has a 40 mo, full exchange warranty (best warranty) and was cheaper than anyone else.
Buy the battery and install it yourself. Chevy wanted $160 to install it.
Walmart didn't carry a battery for my '08 base model, but did carry one for a z06. Different size, location, etc. Go figure.

 

I noticed delcos went from 7 yrs war to 40 month.

 

Warranties seem to be getting shorter and shorter....My last Duracell lasted 5 yrs (just replaced it last week). It's a 78, 690 CCA....

 

why dont you have it tested to see if its still good

 

I have a green top Interstate in mine. New in 2018. With a cutoff switch. Sadly, this last time it sat for 6 mos untouched not on a tender.

When my car sits that long if takes a little cranking to prime the carb. Even after 6 mos it cranked strong and works fine.

 

My original AC Delco lasted 20 years...'96. No battery has come close to that since!

Walmart is now my choice for all car battery's. There's a round sticker on top that has the month & year it was made.
Just pick out the newest one...

 

If it’s working fine let it be…