The Ford Barn

Tom in SW VA · 10-03-2016, 09:32 PM

If you install an eight (8) volt battery, do you have to make any electrical changes ?

Thanking you in advance.............................

Tom in SW VA

Charlie Stephens · 10-03-2016, 10:48 PM

Search the archives. Most people regret installing an 8 volt battery. Fix what is wrong with your 6 volt system or go 12 volts negative ground. By the way what is wrong with your existing system? Also you should have posted this in the Model A forum (I assume from your profile that is what you are working on).

Charlie Stephens

willowbilly3 · 10-04-2016, 06:34 AM

I agree with Charlie, if your 6 volt system is all up to snuff, you shouldn't need 8 volts.
We switched a lot of old farm trucks over to 8 volt back in the day and even did a series/parallel on some so only the starter got 12 volts. IMO, 6 volt systems are a lot less forgiving than 12, everything has to be working right. Any bad grounds or resistance in the system and you have a balky starter. Also the starter itself has to be in good order with no drag. Any excessive starter draw leaves insufficient voltage to fire the points enough.

If you do switch to 8 volts, you can usually tweak the regulator to make the genny charge 8 volts.

dmsfrr · 10-04-2016, 12:14 PM

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A couple common problems that cause sluggish starting on 6v vehicles...

(as previously mentioned) Battery & starter cable connections that aren't spotless, at all ends.
The battery ground cable should fasten to the engine block.
It's the shortest path to ground with the highest current capacity and least number of connections to the starter. (except for grounding the battery cable to the starter itself)

Having generic replacement battery & starter cables from the rack at the corner auto parts store.
Most of them are #2, #4 or even #6 gauge wire, which is insufficient for a 6v starter.
A 6v electrical system uses double the current of a 12v system and needs battery & starter cables of #1 or #0 gauge to function well.
Any switch, wire or connection in the starter system that is the weakest link defeats all the rest.
.
.

10-04-2016, 06:34 AM	#3
willowbilly3 Senior Member Join Date: Sep 2011 Location: Black Hills, SD Posts: 577	Re: 8 volt battery I agree with Charlie, if your 6 volt system is all up to snuff, you shouldn't need 8 volts. We switched a lot of old farm trucks over to 8 volt back in the day and even did a series/parallel on some so only the starter got 12 volts. IMO, 6 volt systems are a lot less forgiving than 12, everything has to be working right. Any bad grounds or resistance in the system and you have a balky starter. Also the starter itself has to be in good order with no drag. Any excessive starter draw leaves insufficient voltage to fire the points enough. If you do switch to 8 volts, you can usually tweak the regulator to make the genny charge 8 volts.

10-03-2016, 09:32 PM	#1
Tom in SW VA Senior Member Join Date: May 2010 Location: Richlands, VA Posts: 533	8 volt battery If you install an eight (8) volt battery, do you have to make any electrical changes ? Thanking you in advance............................. Tom in SW VA

10-03-2016, 10:48 PM	#2
Charlie Stephens Senior Member Join Date: May 2010 Location: Southern California Posts: 7,032	Re: 8 volt battery Search the archives. Most people regret installing an 8 volt battery. Fix what is wrong with your 6 volt system or go 12 volts negative ground. By the way what is wrong with your existing system? Also you should have posted this in the Model A forum (I assume from your profile that is what you are working on). Charlie Stephens

10-04-2016, 12:14 PM	#4
dmsfrr Senior Member Join Date: Aug 2012 Location: Abq, NM Posts: 3,607	Re: 8 volt battery Sponsored Links (Register now to hide all advertisements) A couple common problems that cause sluggish starting on 6v vehicles... (as previously mentioned) Battery & starter cable connections that aren't spotless, at all ends. The battery ground cable should fasten to the engine block. It's the shortest path to ground with the highest current capacity and least number of connections to the starter. (except for grounding the battery cable to the starter itself) Having generic replacement battery & starter cables from the rack at the corner auto parts store. Most of them are #2, #4 or even #6 gauge wire, which is insufficient for a 6v starter. A 6v electrical system uses double the current of a 12v system and needs battery & starter cables of #1 or #0 gauge to function well. Any switch, wire or connection in the starter system that is the weakest link defeats all the rest. . . Last edited by dmsfrr; 10-04-2016 at 08:10 PM.