8 volt battery

Ricky Mullen

Junior Member
I was asked to get a 1947 Mercury started. Instead of a six volt battery, it had an eight volt. Does that effectively change anything, or should I get a six?
 
If you have to go to a 8 Volt battery you have a situation that need fixing. Better to fix the problem.
 
X2 on post 3. Better get a supply of light bulbs.. You will need them if you keep the 8 volt battery. Make SURE all ground connections are good.
 
If you have to go to a 8 Volt battery you have a situation that need fixing. Better to fix the problem.

Couldn't agree more - fix the problem, don't hide it and potentially create more problems with an eight volt battery.
 
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Previous owner had the eight volt in. I think the generator would charge a six but not an eight, enough, anyway. I was looking for advice.
 
The ford generator will charge the eight volt battery just fine. If its the third brush type generator you may have to adjust the third brush setting up a little. If you have a two brush generator with a three unit regulator then the regulator and cut out would need a little adjustment by someone who knows what they are doing. Regards, Kevin.
 
My 55 Vicky arrived with an 8 volt battery installed. I replaced it with the proper 6 volt battery and reset the regulator to charge at 7.2 volts. Cranks over well after I cleaned and wire-brushed all starting circuit connections.
 
I was asked to get a 1947 Mercury started. Instead of a six volt battery, it had an eight volt. Does that effectively change anything, or should I get a six?

Guys, the original post is above. He was asking if it affected getting a car started.

The short answer, no. If the battery holds the charge and starts the car you’ll be fine.

If there is nothing broken, don’t fix it. I used to live in a rural and remote town. I ordered a 6v battery for my car. After a few days an 8v battery showed up by mistake. I didn’t want to wait the week or more to return and get the new battery. I ran an 8v battery in the car until it died 6 or 7 years later. I didn’t adjust anything, and I didn’t replace a single lightbulb. I drove the car on several trips too. I still have the car, and the 8v battery is long gone, but the light bulbs are older than I am.

Most people that say it causes harm have never run them. Good,luck!
 
Guys, the original post is above. He was asking if it affected getting a car started.

The short answer, no. If the battery holds the charge and starts the car you’ll be fine.

If there is nothing broken, don’t fix it. I used to live in a rural and remote town. I ordered a 6v battery for my car. After a few days an 8v battery showed up by mistake. I didn’t want to wait the week or more to return and get the new battery. I ran an 8v battery in the car until it died 6 or 7 years later. I didn’t adjust anything, and I didn’t replace a single lightbulb. I drove the car on several trips too. I still have the car, and the 8v battery is long gone, but the light bulbs are older than I am.

Most people that say it causes harm have never run them. Good,luck!

Did you ever check the charging voltage? To properly charge an 8 volt battery, the regulator needs to be set at about 9.4 volts. Since you did not adjust anything, you never had enough voltage to fully charge that 8 volt battery. That's why you didn't burn out any bulbs.
 
I know my response to the 8v question is a little off topic. ( 8v battery 6v system)
Having been raised in rural Eastern Idaho in the '40's, early '50 I have had many personal experiences with 8v batteries in 6v vehicles, I ran one in my '36 coupe for several years until I moved to California where I did not experience sub zero temps.
I never had any problems with bulbs and/or accessories. In the good ole days the bulb packages generally said 6/8 v on the package and/or bulb.
 
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Where the heck are these people finding these 8 volt batteries? A "Google" search yielded only golf cart batteries, which appear to be too large to fit these old cars. They're expensive, too!
 
In reading all these glad reports of 8 volt batteries, I have to add that to have your hood up to reveal an 8v battery at a Coffee & Cars, you stand a good chance to get a few snickers and disparaging remarks. Best to do the right thing and clean your terminals, replace your dimmer switch, and run the 6v it was built to run with. If your headlights are still dim, power them from a relay which in turn is switched by the dimmer switch.
 
I wonder, just how many of the contributors to this topic have actually used, or tried to use and 8v battery in a 6v vehicle? Or is their opinion/contribution based on hearsay and/or myths.
i also wonder just how many people at a Coffee & Cars event are going to check to see what kind of a battery a vehicle has..
Of course a quick glance to count the number of cells in a battery will reveal the voltage of same. Three equals 6, four equals 8, and so on.
 
I have never used an 8 volt battery. However, my opinion is not based on "hearsay and/or myths". It is based on the concept that restoring these cars means getting them back to as close to original as possible, and they never came with 8 volt batteries. In addition, if they don't perform adequately on six volts, there is something wrong that should be corrected. NO car enthusiast worth his salt reverts to "band-aids" on a permanent basis. If I see an 8 volt battery in an old Ford, I automatically assume the owner is either lazy or incompetent.

I run the original 6 volt system in my '51 with no problems whatsoever; easy starting, bright headlights, and all.
 
I have never used an 8 volt battery. However, my opinion is not based on "hearsay and/or myths". It is based on the concept that restoring these cars means getting them back to as close to original as possible, and they never came with 8 volt batteries. In addition, if they don't perform adequately on six volts, there is something wrong that should be corrected. NO car enthusiast worth his salt reverts to "band-aids" on a permanent basis. If I see an 8 volt battery in an old Ford, I automatically assume the owner is either lazy or incompetent.

I run the original 6 volt system in my '51 with no problems whatsoever; easy starting, bright headlights, and all.


A very safe assumption.
 
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