8 Volt battery used in a 34 Buick?

[Frank Wilkie]

Has anyone had any experience in using a 8 volt battery in a 1934-35 Buick?  Would the bulbs hold up?  Why I'm considering it is because the starter seems a little draggy and takes a long time for it to start. It was rebuilt before I purchased the car.  I have cleaned the negative battery connection to the frame and of course the 6 volt battery connections. 

[Rock10]

I don't think the generator would charge it.

[Steves Buick]

Make sure you have the proper size cables, run your negative battery cable directly to the starter. I don't a real need for a 8 volt battery if everything works. I use a 6 volt optima and it's fine. 

[Matt Harwood]

To make a 6 volt car start using 6 volts:

 

1. Load test battery to be sure it's putting out adequate voltage and current. As mentioned, Optimas really do pack a wallop.

2. Big battery cables. They should be as big as your thumb.

3. Clean all grounds.

4. Add a ground cable from battery ground to starter housing.

5. Add a ground cable from engine block to frame.

6. Clean all grounds (yes, I said it twice).

7. Rebuild starter if necessary (new bushings can make a world of difference).

 

Always remember that old cars cranked much slower than modern cars, yet they still fired. My '35 Lincoln turns over at like 30 RPM and every Packard 356 I've had grinds so slowly that you'd think the battery is already dead. Totally normal.

 

Also make sure your ignition system is in top shape. The starter is pulling most of the battery's power so any flaws in the ignition system will be revealed during cranking. If you're running an electric fuel pump during cranking, make sure it isn't connected to the ignition for power--pull your power from someplace else, there's not enough to spare if you pull it from the ignition switch.

 

This is a solvable problem. 8-volt batteries are band-aids at best. Fix it right and you won't have any more problems.

[Frank Wilkie]

Thank you for all the input.. This assured me of what I had expected to hear.. I normally don't like to make any changes from originality..   Staying 6 volt.. 

[37Special]

Optima batteries helps a lot.  I'm new to pre war so maybe I'm not used to 6 volt as much but I installed an optima and changed my cables and wow!  Huge improvement!

Edited September 13, 2021 by Nichalicious (see edit history)

[Frank DuVal]

If one was to put in an 8 volt battery, to charge it you have to adjust the regulator or third brush generator up to 9.4 volts to make it charge! That's why I say fix it and keep the 6 volt system. Less stress on the charging circuit.

 

Make or buy 2/0 awg cables. 4/0 if you can find them.

[Morgan Wright]

7 minutes ago, Frank DuVal said:

 

Make or buy 2/0 awg cables. 4/0 if you can find them.

 

Yeah 6V means the amps double so you need 0 or 2/0 I think 4/0 is overkill. Any way, you need thicker cables than with 12V 

[Oldtech]

My experience with 8 volt batteries is limited, but a few years ago we thought we should get a couple for our museum cars that we run. They cranked the car wonderfully - for the first year, then they lost power badly - all of them. We had noticed that they seemed lightweight compared to a  good 6 volt.  So, back to 6 volts and they are fine. 

[Larry Schramm]

Go back to the correct size cables.  Be sure to have clean contact surfaces that the cable terminals attach to. 

 

To help to be sure of a good mechanical connection of the cable terminal to the cable, solder the terminal to the cable after crimping.  Soldering fixes a lot of crimping issues, both immediately and over time.