dangers of an 8 volt
- Thread starter CB919ER
- Start date
Charlie Stephens
Well-known member
What about getting a replacement battery or generator (alternator) while on a tour? Why not just fix the real problem (usually the cables are too small). What problem is 8 volts supposed to solve? If you must do something, change to 12 volts.
Charlie Stephens
Charlie Stephens
Scottio57
Senior Member
Dad always used 8 volt batteries as have I since the 70s without any problems on all the old cars and trucks we've had. I run an 8 volt in my A now not to correct any problems I just like that little extra power. A six volt generator or alternator will keep it charged just fine and it can be charged up with any 6 volt charger. A good working 6 volt charging system typically puts out 8 volts.
Patrick L.
Well-known member
8v is just an old bandaid. It was thought to be a fix.
Just keep the grounds clean and use the correct size wires and you'l be fine.
I guess the main question is why did he say that ?
Just keep the grounds clean and use the correct size wires and you'l be fine.
I guess the main question is why did he say that ?
hardtimes
Well-known member
What kind of shop ? Donut shop tech
What were his reason(s) for suggesting using an 8 volt battery ?
Usually, 'things' are/should be done for a reason. For example, if wanting more cranking power or whatever, I'd go to 12Volts. I do not see any danger faced by using 8 volts, unless you may want / use a 12v accessory ?
Terry NJ
Well-known member
I used one in my coupe and it would burn the light bulbs out every time you turned them on. There were no problems charging it. The answer I found to all my 6V problems was to add an auxiliary ground cable to the engine. Although it's not recommended, even a 12 volt cable will do (As an auxiliary). A 6V is better. Connect it to a bell housing bolt and the bottom of the flange of the frame, same bolt, only one connection on top and one on the bottom. The starter will spin faster and and it will crank longer before getting weak.
Terry
Terry
Bill G
Well-known member
I am new to Model A's but not to electricity issues. Running 8 volts on a Model A without any other items is probably within tolerance of light bulbs and the ignition system, so you aren't going to burn anything up. The generator will likely charge it up too.
A higher voltage supply means that to get the same wattage out of any device, you will have less current (Amps), and thus will need a smaller conductor and bad grounding systems can be masked by having the higher voltage.
So, maybe the first step is to check to make sure all conductors are the right gauge wire, and that all connectors are solid and don't have any resistance and that all grounds are as grounded as can be. As an example of a ground, my headlight buckets have horribly corroded swivel posts. It is real hard to get the headlights to be bright even while the engine is revved up because the ground sucks. That all needs to be cleaned out real good. If it were not for the corrosion, the large bolts would be more than ample for carrying the current of the headlamps.
The other hidden thing is all the crimp-on connectors. Age, moisture and even dis-similar metals can create resistive connections that cause trouble. Another example for mine: The after-market ammeter had a connection that was rusty, and this created a high resistance. Because all the operating power of the car goes through the ammeter connections, those in particular have to be the best. These were not. The heat generated from the bad connection only made matters worse. But that was not the entire issue. Because of that low voltage, you had to hold a match up to the lights to see if they were lit when the car was not turned on. Really bad Because of this low voltage, the generator cut-off sees it as the equivalent of a dead battery and puts out the maximum amount of voltage it can to overcome that. The end result was that with the car off, you could barely see the headlights. With it running, the generator was putting out so much, you'd think I was running Halogen headlights. That would burn a headlight out after a while.
So, the key to good 6-volt operations is good grounds, good connectors and proper gauge wire.
A higher voltage supply means that to get the same wattage out of any device, you will have less current (Amps), and thus will need a smaller conductor and bad grounding systems can be masked by having the higher voltage.
So, maybe the first step is to check to make sure all conductors are the right gauge wire, and that all connectors are solid and don't have any resistance and that all grounds are as grounded as can be. As an example of a ground, my headlight buckets have horribly corroded swivel posts. It is real hard to get the headlights to be bright even while the engine is revved up because the ground sucks. That all needs to be cleaned out real good. If it were not for the corrosion, the large bolts would be more than ample for carrying the current of the headlamps.
The other hidden thing is all the crimp-on connectors. Age, moisture and even dis-similar metals can create resistive connections that cause trouble. Another example for mine: The after-market ammeter had a connection that was rusty, and this created a high resistance. Because all the operating power of the car goes through the ammeter connections, those in particular have to be the best. These were not. The heat generated from the bad connection only made matters worse. But that was not the entire issue. Because of that low voltage, you had to hold a match up to the lights to see if they were lit when the car was not turned on. Really bad Because of this low voltage, the generator cut-off sees it as the equivalent of a dead battery and puts out the maximum amount of voltage it can to overcome that. The end result was that with the car off, you could barely see the headlights. With it running, the generator was putting out so much, you'd think I was running Halogen headlights. That would burn a headlight out after a while.
So, the key to good 6-volt operations is good grounds, good connectors and proper gauge wire.
We're talking 8 volt automotive batteries here. They are the same size as regular 6 and 12 V. automotive batteries.
Tom Wesenberg
Well-known member
8 volt batteries suck, but if I had 4 matching 8 volt batteries, I could connect them to my 32 volt Delco Light Plant. 
H. L. Chauvin
Well-known member
FWIW:
Our 1955 (8) cylinder Chrysler came with a Chrysler installed six (6) volt battery, dual distributor ignition points ....... and we never had problems with same ...... even thought this huge (8) cylinder engine was just about twice the size of a Model A (4) cylinder engine plus it had a much greater compression ratio.
If someone is trying achieve increased Model A performance, speed, and MPG .......... in my humble opinion ....... installing an (8) volt battery in a Model A is about as effective in achieving these improvements as it is to make your race horse wear a Jock Strap, Sunglasses, and Red Tennis Shoes so he can outrun the other race horses.
Our 1955 (8) cylinder Chrysler came with a Chrysler installed six (6) volt battery, dual distributor ignition points ....... and we never had problems with same ...... even thought this huge (8) cylinder engine was just about twice the size of a Model A (4) cylinder engine plus it had a much greater compression ratio.
If someone is trying achieve increased Model A performance, speed, and MPG .......... in my humble opinion ....... installing an (8) volt battery in a Model A is about as effective in achieving these improvements as it is to make your race horse wear a Jock Strap, Sunglasses, and Red Tennis Shoes so he can outrun the other race horses.
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Brendan
Well-known member
why?
Charlie Stephens
Well-known member
If 8 is good 12 is better. The other good part about 12 is that everyone knows how to work on it and parts are readily available. If you are trying to improve the starting be sure you have the larger cables designed for 6 volts and the starter isn't ready for a rebuild. For lights get the reflectors from Bratton's (NOT ANYWHERE ELSE!!!) and the most powerful 6 volt bulbs available. If you go 12 volts get the "Brite" bulbs from Ron Francis Wire Works, https://www.ronfrancis.com, (800) 292-1940. Still get the reflectors from Bratton's. If you want it to run better, tune it up, changing the voltage won't affect how it runs.
Charlie Stephens
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Tom Wesenberg
Well-known member
Why do you need faster cranking?
My engine will start right up with a hand crank, and that's much slower than the 6 volt starter.
My engine will start right up with a hand crank, and that's much slower than the 6 volt starter.
CB919ER
Senior Member
Thanks for all the tips guys! you have all been a tremendous help
After my first night drive I'll see if I need more light, and if I do I'll definitely look into these. Thanks again!
After my first night drive I'll see if I need more light, and if I do I'll definitely look into these. Thanks again!
Tom Wesenberg
Well-known member
My 28 Phaeton has the original headlamps and bulbs and has good light for night driving. Make sure your reflectors are in good condition and make sure each headlamp is correctly aimed and focused.
Willie Krash
Well-known member
In my Alternator/Generator shop I have been asked about 8V for 38 years. My answer is why? It made it this long without 8V.
It becomes very problematic on 2 and 3 unit regulators where the voltage can be set.
As to your headlights follow the advice given.
Use a two by four to "square" up the headlights and once you've done that take a level and put each light one half a bubble off plumb.
It becomes very problematic on 2 and 3 unit regulators where the voltage can be set.
As to your headlights follow the advice given.
Use a two by four to "square" up the headlights and once you've done that take a level and put each light one half a bubble off plumb.