1950s 1959 Cadillac battery issue

[Cadillac Jack 82]

So, without testing the generator or voltage regulator output what would cause the battery to just die?  It was a brand-new battery and my generator light only comes on at times when starting the car.  I've sinced ditched the battery for a new replacement however I'm concerned that it'll die too.  Any clues?  Also are there any modern batteries that'll fit the battery tray or am I stuck waiting for a repro from Battery Warehouse?

[Gabe Davis]

I run a 7527F battery from NAPA in my '59 Coupe DeVille. Its a big beast and is a tight fit but will go in the stock battery tray with a little wiggling.



I don't have the original strap that goes across the top so I'm not sure if it will fit with a stock one. The threaded rods that come up from the tray are original.



12 3/8" x 9" x 6 3/4"

https://www.napaonline.com/en/p/BAT7527F

It has been very good at turning the car over hot. The first one I had lasted 8 years using a battery tender.

[Cadillac Jack 82]

Thanks Gabe I believe that was the first battery I bought but it barely fit and stuck up higher than I was comfortable with...so I ended up with a smaller battery.  Works well but I'm doubtful it'll last long.

[Clewisiii]

Could voltage regulator generator polarity be an issue for charging.

[bcroe]

The car might be a good candidate for a voltmeter,
to tell what is going on.  I have had problems with
loads that did not get turned off.  One was a trunk
light with a bad switch.  Another was brake lights
that did not always release, bad switch adjustment. 
I got into the habit of looking back as I left. 
good luck, Bruce Roe

[gkhashem]

I have experienced "new" batteries that just failed. Did you test the battery and did it go bad?

How long did it work?  How new was it?

[The Tassie Devil(le)]

Here is the battery that I installed in my '60 CDV, and it was the largest one I could find, and I fitted a Battery Minder as the car wasn't used as much as a normal car would be.

I have one of these in both my "lesser-used" cars.

The Battery I used from memory was a deep cycle one, and never let me down.   But, I did have to create a taller hold-down.

Bruce.

[V63]

The optima red top is a great option, with very high cranking amps. Smaller in size it's often the base battery hidden inside  reproduction batteries.

There is not enough information about your particular dead battery situation provided but I suspect you approached the car after sitting and the battery was dead?

That scenario is likely a system 'draw', some suggestions were affected above.

If you have a more modern 'smart' battery charger they will NOT charge a completely dead battery, I like to buy the 'old' chargers instead. OPTIMA batteries do not like to be fully discharged.

[Chopper1942]

You may have a parasatic draw. With the key turned off, the only draw you should have is the clock. Do you have a digital multi-meter? If so, remove the negative battery cable from the battery. Close all doors and if you have an under hood light, remove the bulb. Select amps on the DMM. Connect the DMM between the negative battery cable and the battery post. If the reading is less than 1 amp, switch the DMM to mA (milliamps). The reading should be close to 0 mA, at least > 0.10 mA.

If the reading is high, pull 1 fuse at a time to find the circuit that is causing the draw. Trunk mercury switch and glove box lights are the usual suspects. Look for corrosion in connectors.

If you have converted from a DC generator to an AC generator (alternator), unplug the connector at the generator. If the draw is gone, the regulator or diode trio has failed .

If the reading is OK and you have an underhood light, position the DMM so you can close the hood and reinstall the bulb and close the hood. If the reading is now high, the mercury switch in the underhood light is bad.

The battery run down time will vary depending on the batteries reserve capacity. If the reserve capacity is higher, then the battery run down time may be longer. If the reserve capacity is lower, then the battery run down time may be shorter. The graph below indicates roughly how many days a 690 cold cranking amperage battery with a 110 min. reserve capacity starting at 80 percent state of charge will last with a constant current draw until it reaches 50 percent state of charge. Differences in battery reserve capacity and temperature will affect the results.

Current Drain        Days

25 mA                33
50 mA                16.5
75 mA                11
100 mA               8.25
250 mA               3.3
500 mA               1.65
750 mA               1
1 A                  0.8
2 A                  0.4

This chart is what we use to diag parasitic draw on computer vehicles. Typically, we like to see >50 mA draw. As you can see, if you have a newer vehicle that sits without being driven often, you should put a battery maintainer on it.

[59-in-pieces]

Bruce,

Are my eyes going even worse, but is the battery on the "wrong" side of the car in the 3rd picture, because the fender brace to the radiator core support look like a Cad's.

And if it is in one of your other cars, is it reversed because of the left hand drive nonsense.
And, is that a "Resale Red" respray.
Bruce only kidding with you.

Have fun,
Steve B.

[The Tassie Devil(le)]

G'day Steve,

All pictures are of the same 1960 Cadillac Coupe DeVille

I didn't show the picture of my other "lesser-used" car, because it is a Ford, and therefore not allowed to be shown.

The Re-sale Red paint was put there well before the car left USA soil, and I am pretty sure it was painted because all the side trim had been removed.   I am tipping that the car had been in a bender and the Left Rear Quarter moulding got trashed, as there is evidence of repairs in that area from inside the trunk.   Actually, I like the look without the side trim.

Life is fun.

Bruce.

[59-in-pieces]

Bruce,

The car didn't come from the US with lefty driving.
So with the battery on the left it is in the US.
And, battery on right is with lefty conversion???

I'm one to talk about resale red.
I deliberately painted my first Eldo B. Seminole Red - not an Eldo color.

Have fun,
Steve B.

[The Tassie Devil(le)]

The car was converted when it came to Australia, and from what I can gather, it was around 1974.   At the same time they pulled out the 390 and Auto and installed a BBC 454 and TH400.   Plus, reupholstered the car in Italian Shoe Leather.  The owner had some Shoe Shops, hence the Leather.   Boy, it was nice and soft.

As for the battery location, I always thought it was sited where mine was, as I have seen a 1960 LHD with the battery in the same position.   Picture shown.

Bruce.

[59-in-pieces]

Bruce,

Apologies.

I put down my scotch and figured out that picture 1 was taken from outside the car, looking into the engine bay.
The right picture was take from the inside of the car - engine bay - looking out.

So not a case of the migrating battery or the lefty conversion, I needed a change of perspective.
Isn't that always the case in understanding the other guy.

Have fun.
Steve B.

[The Tassie Devil(le)]

That's okay Steve.   Too much Scotch will do that to you.  

Bruce.

[Jon S]

I run a 7527F battery from NAPA in my '59 Coupe DeVille. Its a big beast and is a tight fit but will go in the stock battery tray with a little wiggling.



I don't have the original strap that goes across the top so I'm not sure if it will fit with a stock one. The threaded rods that come up from the tray are original.

You have a Ford battery in your car. You should have a Group 27; NOT 27F.  I run a group 27 Die Hard dressed up:

[David Greenburg]

Most group 27 batteries will fit if you shave off the hold down flanges on the sides. If you want maximum CCA, check out the X2 sold by Batteries Plus of all places. It's an Odyssey battery nderneath. 930 CCA. A more affordable option is the Napa Legend, which fit in my '61 (uses the same Grp 60 as '59-'60) with no modification.

[bcroe]

Bruce,
Are my eyes going even worse, but is the battery on the "wrong" side of the car
Bruce only kidding with you.  Steve B.

Every car I have ever seen had a battery on the same side
as the starter.  So an engine swap might change that.
Bruce Roe

[Cadillac Jack 82]

So far so good.  I think I just had a defective battery.  She's not had an issue since I switched out the battery.  I'd eventually like to get a repro one but that can wait.

[BigV8]

For my 1959's battery replacement I found a battery that would fit the narrow battery box and was very affordable. At a local Menards store I found the AC/Delco Group 24FS battery was only 6 1/4" wide at the bottom and 6 3/8" wide on the main battery body. The +/- post locations worked well for me. I did not have to shave off the battery hold-down protrusions for it to fit.

It cost $112 on sale, and I received an additional 11%-off Menards rebate. The battery has a 36-month free replacement to boot. The only downside is the CCAs are listed as 600, which is less than I would like, but it is working fine so far.

I may put a tar-topper battery cover and old-style Delco battery decal on it to give it that some-what vintage appearance.