74 Lesabre Convertible - I need some help with getting the right battery!

[JoelsBuicks]

I just purchased a 1974 Lesabre Luxus Convertible. I'm going to try and start it and drive it home on Friday. It does not have a battery but it is a very original car with only 40K miles. When I looked at the car, I remember it having battery cable ends that screw into threads on a battery and not post-type connections. I want to buy a battery that is supposed to fit the car but the car is 50 miles away and I can't remember whether ground is closer to the center of the car or if it is the hot cable or whether they are toward the front of the car or back. All I know is that this car is very original and garage kept. Can someone tell me a size or battery number appropriate for an original car? My Buicks are all older - I have no experience with this vintage. Also, I have to buy the battery and take it with me - there are no places that sell batteries near this car.

Thank You!

Edited April 8, 2015 by JoelsBuicks
spelling (see edit history)

[leosdad]

My 73 Centurion with a 455 uses a Group 78.A 74 LeSabre should be the same-Have fun

[JoelsBuicks]

Thanks for the help, it's exactly what I needed to know.

Joel

[JohnD1956]

BTW, I recently replaced the battery in the Electra. I can't recall if I got the 78 or 78-A. One had both top posts and side terminals, the other just side terminals. In the Delco brand the one with both top posts and side terminals had a higher power rating, so I went with that. Conveniently, it was a lower cost for the Delco battery than for others I considered inferior. Time will tell if I made the right choice.

One more thing, the Delco one was the only one where I was definitively told the battery case was reinforced to prevent that positive side terminal from leaking. I have seen that on two 78 series batteries and have come to learn this was a routine problem for several years in all the 78 series batteries. That's why I replaced my otherwise well functioning battery to begin with. That leaking acid sure does ruin the metal underneath if it stays on there too long.

[old-tank]

That leaking acid sure does ruin the metal underneath if it stays on there too long.

Consider an Optima or AGM battery if you care about those common lead acid batteries slobbering all over.

[NTX5467]

The "dual terminal" ACDelco batteries are considered "universal", as they have both types of terminals. That's possibly one reason for the higher CCAs. The people who really need both sets of terminals usually have some sort of aftermarket sound system and high-power amps. The dual terminals allows them to use the side terminals to go to the "car" and the top terminals to connect the "sound system amp" to, which works better than having one huge connector and them split "the juice" downstream from the terminal.

It was, unfortunately, quite common for the 78-series batteries to have issues with acid leaks at the side terminal (usually just one, but that was enough!). There were many theories behind such large numbers of failures. One was that the threads in the "lug" were not cut deep enough for the length of the bolt in the battery terminal. If it was tightened up, it put a small fissure in the lug, which eventually let the acid out. Then there was the theory that over-tightening did it, with the normal length bolt (there were ONLY two lengths of battery bolts, much different from each other). Nobody really admitted to knowing what it was, though.

In reality, I strongly suspect the same lugs were used in the 78-series and the smaller series, or other similar ACDelco batteries, which had NO such issues. FWD Cadillacs and others, with the batteries under the back seat, also had acid leak issues (for which GM issued a "fix kit" to repair the floorpan and also a new battery tray). OTHER than just the battery tray issues, you also had to replace the affected battery cable for a complete fix. Perhaps . . . it might not have been just the design or the casting of the lug, but the material in the lug itself that was the issue, but then again, why just on those FEW sizes of ACDelco batteries. THEN, later, I found out that other brands were having similar issues, so it was not just ACDelco batteries having those issues!

Seems like all of the current ACDelco batteries are now "AGM" batteries?

Congrats on your "find"! It should make a really nice car!

Please keep us posted on your progress!

NTX5467