Car batteries...'72 vette

[mrvette]

amp meter says like .01 drain when still in the garage....but the battery life is marginal at best.....car ran fine yesterday....but DVM says when starting at the battery terminals....down to 5 volts.....something not right.....

but open circuit even with headlights on measures 12 or so....

anyone??

I think it's a bad battery but only some 2 years old Auto Zone....

[Torqaholic]

Gotta be aliens

[Vegas]

I think that you answered your own question.

[mrvette]

Originally Posted by Vegas

I think that you answered your own question.

Ten milliamps of draw is nothing to a car bat.....and it ran fine yesterday....

so go figger......

[Stevedore]

Assuming that you've checked the terminal cleanliness & tightness, I'd guess some sort of internal fault, break, failure, or whatever. I've had some strange behaviors out of car batteries in my years; when something just makes no sense, I tend to replace the battery. 2 years seems pretty young though.

[Giraffe (He/Him)]

It needs new tubes. Still got your suitcase from the 60's?

[Rodnok1]

Originally Posted by mrvette

amp meter says like .01 drain when still in the garage....but the battery life is marginal at best.....car ran fine yesterday....but DVM says when starting at the battery terminals....down to 5 volts.....something not right.....

but open circuit even with headlights on measures 12 or so....

anyone??

I think it's a bad battery but only some 2 years old Auto Zone....

Auto zone battery would be the problem...

[Jobaka]

I had an Optima battery die a premature death because I didn't drive the car very often. Turns out some batteries just won't survive the discharge/recharge cycles associated with infrequent use. I replaced mine with a new Optima and keep it on the trickle charger any time the car is not in use. It's been several years and I've had no more problems.

How often do you drive your '72?

[mrvette]

Originally Posted by Jobaka

I had an Optima battery die a premature death because I didn't drive the car very often. Turns out some batteries just won't survive the discharge/recharge cycles associated with infrequent use. I replaced mine with a new Optima and keep it on the trickle charger any time the car is not in use. It's been several years and I've had no more problems.

How often do you drive your '72?

Recent vacation for a week, vette sat in garage, drove it maybe 2 times since back a week ago, drove it yesterday....hung a DVM on battery terms directly....~12.5 or so.....hit starter drops to 5 volts and of course no crank....

Anyone else with crappy newer battinators??? I suspect China junk....

[Rodnok1]

Originally Posted by mrvette

Recent vacation for a week, vette sat in garage, drove it maybe 2 times since back a week ago, drove it yesterday....hung a DVM on battery terms directly....~12.5 or so.....hit starter drops to 5 volts and of course no crank....

Anyone else with crappy newer battinators??? I suspect China junk....

That almost sounds like a connection problem.

[Grey Ghost]

Check the big cable at the starter. Make sure all those and the grounds are clean.

Does it have a ballast resistor or the famous GM fusible link?

[Torqaholic]

Originally Posted by mrvette

....

Anyone else with crappy newer battinators??? I suspect China junk....

Nope, batteries in my vehicles are Interstate USA. No complaints.

[Olustee bus]

That is why I put a battery cutoff switch. Slow drain.

[mrvette]

SO, after messing with it yesterday, and putting charger on it, and measuring drain, and seeing it as just ten milliamps, computer injection memory storage, not likely an issue.....

so first thing this AM, I start the car as if nothing happened....WTF??

how in hell can a battery have an overnight failure like that and then recover by some miracle?? internal structual failure?? if so, how in HELL can it cure itself??

[Strats-N-Vettes]

Originally Posted by mrvette

SO, after messing with it yesterday, and putting charger on it, and measuring drain, and seeing it as just ten milliamps, computer injection memory storage, not likely an issue.....

so first thing this AM, I start the car as if nothing happened....WTF??

how in hell can a battery have an overnight failure like that and then recover by some miracle?? internal structual failure?? if so, how in HELL can it cure itself??

It's bad connections....clean, inspect, tighten....battery, alternator, and starter.
Properly diagnose after that is done.

[mrvette]

Originally Posted by Strats-N-Vettes

It's bad connections....clean, inspect, tighten....battery, alternator, and starter.
Properly diagnose after that is done.

I am putting my FLUKE DVM directly on the battery posts, two screw/bolt terminals on top of the battery next to the unused typical lead studs....done by the battery maker, not some aftermarket mess.....

and what is with upon looking up at Auto Zone site, all their batteries are now TWO HUNDRED BUX???......

[StaticCling]

Originally Posted by Rodnok1

Auto zone battery would be the problem...

Why? There are only a few manufacturers of car batteries anyway. I believe the Duralast batteries are made by Johnson Controls, which are OEM on a lot of cars...they manufacture several other brands, including Interstate. Exide is the other company that manufacture car batteries.

The last Wal-Mart battery I had on my truck was manufactured by, you guessed it, Johnson Controls (the OEM battery was made by Johnson Controls as well) - I'm currently running a Duralast Gold, which replaced an Optima that went kaput after one year.

[StaticCling]

Originally Posted by mrvette

I am putting my FLUKE DVM directly on the battery posts, two screw/bolt terminals on top of the battery next to the unused typical lead studs....done by the battery maker, not some aftermarket mess.....

and what is with upon looking up at Auto Zone site, all their batteries are now TWO HUNDRED BUX???......

They have gone up a lot the last few years.

[6spdC6]

Originally Posted by mrvette

SO, after messing with it yesterday, and putting charger on it, and measuring drain, and seeing it as just ten milliamps, computer injection memory storage, not likely an issue.....

so first thing this AM, I start the car as if nothing happened....WTF??

how in hell can a battery have an overnight failure like that and then recover by some miracle?? internal structual failure?? if so, how in HELL can it cure itself??

I had a 72 way back when (mid 80s) and I remember the service guys saying that this vechicle has a lot of ground wires, many hard to find and they can cause interesting problems. I only had the car for about 18 months and got rid of it!

[mrvette]

Originally Posted by 6spdC6

I had a 72 way back when (mid 80s) and I remember the service guys saying that this vechicle has a lot of ground wires, many hard to find and they can cause interesting problems. I only had the car for about 18 months and got rid of it!

OLD ET HERE, from the 60's yet, been reworking cars for decades, necessity as well as hobby, and ALL the wiring has been redone in this car....especially the grounds....battery, engine, fans, etc....

SO I decided to take my cphone with me and go battinator shopping stopped into about 6 parts houses......and the cheapest battery of correct size was marked MARINE Deep cycle.....76 bux.....P24 size with good 1/4 inch studs on the top BUTTTTTT the 'more normal' auto batteries in anything approaching the correct size were 200 bux same size batt case....so go figger.....AND it is rare to find any battery with the studs on it for my wiring style.....except the marine batt.....go figger....whole damn shelf full of them 7' high and some 15' wide all them stupid batteries, not a dime worth of difference between them, and the same price too.....WTF???