What Battery?

[Stan]

Back to batteries

This morning I carried the battery to the CS. It had been on the tender since January and the indicator light showed green. Connected the battery and rrrrrrrr
kaput. Pushed the CS from the storage unit and jump started fine. After driving for an hour, turned the car off and re-started about 30 min later, no problem.

Battery is now about 10 years old.

 

[Markos]

I just picked up a Sears Die Hard Gold sealed AGM battery for $170. I have a platinum in my jeep at it's great. Like the previous poster, I'm done with traditional lead acids.

If you buy a battery from Sears, always check out:

htt://www.retailmenot.com for coupons. I got $15 off.

 

[m73]

I always leave my battery cables off when not driving for large periods, not ideal for the clock, but at least the mechanism gets a rest

I also noticed there is a hierarchy to re-attaching the cables, connect them in the wrong order and you get the idea your battery is dead when in fact you must change the connection order....

Off topic...I had two batteries wired in series for my 24v unimog, a superior electrical system in every way....

 

[Stan]

I always leave my battery cables off when not driving for large periods, not ideal for the clock, but at least the mechanism gets a rest

I also noticed there is a hierarchy to re-attaching the cables, connect them in the wrong order and you get the idea your battery is dead when in fact you must change the connection order....

Off topic...I had two batteries wired in series for my 24v unimog, a superior electrical system in every way....

OK so what is the hierarchy?

 

[m73]

Sounds contradicting...but start with the negative....

Hope that solves your issues...

MF

 

[HB Chris]

I think positive first, then ground. Stan, a 10 year old battery is ancient, I am surprised it lasted this long.

 

[jmackro]

I think positive first, then ground. Stan, a 10 year old battery is ancient, I am surprised it lasted this long.

I agree, positive first. The reason is that if your wrench on the "+" terminal comes in contact with ground, it won't spark as long as the negative is still disconnected. Once the "+" terminal is in place, then hook up the negative. If the wrench on the negative terminal comes into contact with ground, again there won't be any sparks

When removing a battery, reverse that order. E.g., disconnect the "-" first.

Stan's batteries last for 10 years because he cleans, waxes, and polishes them each week.

 

[m73]

Avoiding accidents....

Well chaps....two things:

1) I would not want anyone to take my advice w/o proper research, it may be positive first...(safety first!)

2) I am by no means an expert and won't try to sell myself as one....there are many car things I do which are probably not 100% correct across the board.

That being said, negative first for me works, the other way yields nothing...I also pressure fit the clamps (bad --I know) for the bi-weekly start-up in my garage.

And I believe my battery is ~20 years old :roll:, when I find the PO receipt I will post the actual date ( it's at least 10 years old ).

MF

 

[Arde]

I think the order of attachment like Jay says has only safety implications in terms of what happens if you make some unintentional contact but has no impact on whether the battery works or appears to work once connected. The electrical system only experiences the electrical field once both positive and negative terminals are connected. There is no unipolar electrical field I think.

 

[Nicad]

I seem to recall Doug (Decoupe) mentioning that he had two Odyssey pancake batteries mounted flat under the rear seats for anyone who wants a car with no battery in view, less weight and improved weight distribution.

 

[Stan]

how about attaching both positive and negative simultaneously?

 

[Ohmess]

I seem to recall Doug (Decoupe) mentioning that he had two Odyssey pancake batteries mounted flat under the rear seats for anyone who wants a car with no battery in view, less weight and improved weight distribution.

I am considering copying Doug's design for my coupe. Doug has a single Oddessy PC 680 - http://www.odysseybattery.com/extreme_battery_specs.aspx

It is held in place using polyurethane mold created using Por a Cast http://www.sunbeltmaterials.com/syna...duct_lines.htm to hold it in place.

Given that folks tell me the rear strut brace doesn't do much for coupe handling, and requires drilling holds into the rear shock towers, this seems like it may be a better alternative for those of us who want to get the battery out of the front of the car.

 

[Bez]

BOSCH Battery

Is there any difference in the type of battery for the 1972 vs 1973 3.0CS

Bosch lists the following

1972 S4527B

https://www.boschautoparts.com/auto

1973 S5531B (Group 47)

https://www.boschautoparts.com/auto

 

[rsporsche]

the primary difference is the CCA (cold cranking amps) - the S4 is 300cca and the s5 comes in 3 different versions - 480 / 600 + 650. the 5531b is 600cca.

the s4 has a 2 year free replacement / the s5 has a 3 year

 

[David]

I just tried to buy 61 21 8 381 708 at the dealer. I was told it's been replaced with 61 21 2 353 805, which is a little long. But I cut off the ears of the battery on the short side and it fits in the tray now. I did find an older English bloke in the dealers wholesale parts team who did a little leg work and found this as the replacement PN: 61 21 2 353 803. It wasn't in stock so I don't know if it will fit. I will say all the newer BMW branded batteries are way too big to fit in an e9.

Hope this helps any one wanting an "OEM" battery.

 

[Honolulu]

[nevermind]

 

[m5bb]

I have the black Bosch battery in mine.

Looks like it belongs.

Gary

 

[Bez]

Looking for a battery for my 1972 3.0CS and can't seem to find anything. Sears is saying the DieHard Group Size 90 fits (L 9.625 x H 6.875 No width given). Also states the DieHard Gold Group Size 47 (L 9.6 x H 7.5 No width given) fits.

Anyone have either of these in their car?
A DieHard AGM equivalent?

 

[Bert Poliakoff]

Not a for sure thing, but several E24 guys claim the Wallmart batteries are made by Interstate. I have been running one in my DD, in the hot AZ sun for 2 years and no problems. Because of the heat our batteries usually crap out between 18 and 24 months

 

[Markos]

Looking for a battery for my 1972 3.0CS and can't seem to find anything. Sears is saying the DieHard Group Size 90 fits (L 9.625 x H 6.875 No width given). Also states the DieHard Gold Group Size 47 (L 9.6 x H 7.5 No width given) fits.

Anyone have either of these in their car? A DieHard AGM equivalent?

Hi Bez,

I have a diehard gold group 47. I have a Platinum in my Jeep and it works great. With that said I wouldn’t buy a Sears battery this late in the game. Sears will be a distant memory after the CEO sells everything of value off.

Another thing to note about AGM batteries is that your local auto parts store does not have a proper charger for these batteries. This has been a pain point for me over the last year while I track down a battery drain/charging issue. In retrospect, I think a standard lead acid is good enough.