6 volt starter on a 12 volt system

[Dandy Dave]

On 4/12/2024 at 1:38 PM, Norman Biggs said:

Thanks Terry 

The original wiring Is shot.  I would like to install a new radio and speaker.

Then replace the shot wiring so it can do what it is suppose to. Changing to 12 volts will not make bad wiring work better.

[Larry Schramm]

The reason that the manufacturers went to 12 volt to 6 volt is because the wire sizes could be smaller which saves on the cost of copper in the wiring.  Period.  Look at the size of starter cables between a 6 volt system and a 12 volt system as an example.

 

Crappy wiring be it 6 volt or 12 volt is still crappy wiring.  Fix the problem, not the symptom.

 

Some of the things that can be done is to check all of the terminals to ensure the mechanical connection is clean & tight, solder the terminals to the terminal, and be sure there is no areas with damaged insulation.  If you try to solder an old terminal to the wire and you can not solder it chances are that the mechanical connection is bad.  Replace the terminal and you will have clean wire and terminal that you can solder.  Soldering fixes a myriad of ills including bad crimps, etc..  

 

Bad crimps can result in high resistance in the connection which causes things to not work right.  That is why I recommend soldering any questionable connections.

Edited May 12 by Larry Schramm (see edit history)

[human-potato_hybrid]

On 5/11/2024 at 10:48 PM, Century Eight said:

It’s cheaper and just as well to maintain it to factory specs rather than re-inventing the wheel.  I just have to remember its an old car.  Come to think of it, that’s why I have it in the first place.

I'm always surprised how many people fail to consider this when buying an old car. Half the time it's "what do I need to CHANGE to get it going" when it should be "what do I need to FIX to get it going".

 

Basically any car that any average person will buy was a perfectly fine and capable vehicle when it was new, and needs only fixed, not re-engineered. If it's a 1903 or something then yeah maybe it had problems from the factory. But not something from the Model T era onward.

[Ben Bruce aka First Born]

On 4/14/2024 at 10:25 AM, Grimy said:

Additionally, if you "upgrade" (a misnomer in my mind) ANYthing, make a binder with all the new part numbers for the next owner, or for yourself if you keep it long enough to need component replacement.  Example:  Against my strong recommendation, a neighbor bought an early 1950s Chevy pickup that had been substantially modified (engine, trans, etc) and has not been able to drive it for 2 years due to lack of documentation of "upgraded" parts--AND total wiring screwups. 

 

 Then he is a dummy! 😁   An early 1950's Chevrolet pickup is so simple!   IF I could not figure it out, I could stripe all the wire out and start over and have it running much sooner.

 

  Ben

[JACK M]

3 hours ago, Ben Bruce aka First Born said:

 

 Then he is a dummy! 😁   An early 1950's Chevrolet pickup is so simple!   IF I could not figure it out, I could stripe all the wire out and start over and have it running much sooner.

 

  Ben

We have to remember that some people simply do not get it when it comes to electricity and wiring.

And often afraid to ask for help because it is so simple for some of us.

[Frank DuVal]

Ben, you have a 12 volt system in an originally six volt car. This was necessary because you went with EFI, which needed an ECM and matching electronic ignition system. All this ran on 12 volts. The car did not need it, you wanted it to see how a straight eight would do with modern systems on it. 

 

It is the people who "need" to put in a 12 volt battery to get the engine to spin like their 2000+ Silverado that I take issue with.  Just clean the six volt connections and make sure to not use small gauge cables for the starter leads. Way easier!

 

Bad harness? You can buy a pre-made or just lay the old one out on a large sheet of plywood and make your own in the same path, wire colors, size and terminal ends.  Brillman company is a source along with others.

 

And please keep binder/computer file of what all the "new/different than stock" parts are so they can be purchased by the next owner.

 

Sure a 1950 Chevrolet pickup was easy wiring originally, but what was changed? Ben is right that stripping it all out and starting over to remove previous owner mods might be quicker. But, did the swap have points or electronic ignition? GM HEI not hard to wire up, but maybe something else? Transmission non-electronic? Questions, questions. All could be answered with good documentation. Verbal communication is quickly lost. No docs? oops....🤣

 

So that's my recommendation to the OP. Document the changes for the next owner, or you in 20 years (Now what did I do here?).:wink:

[60FlatTop]

I don't know how I missed this topic. They are always so entertaining.

 

Reading this on your computer browser would anyone like the take a guess at what voltage your computer is running on?

 

With all my years in the hobby I do know one good reason for rewiring a car for 12V. The smaller wire would be cheaper. No kidding, I heard copper wire was invented by two Buick owners who got hold of a penny.

[Ben Bruce aka First Born]

Bernie, you never fail to amuse!

 

 Frank, I don't totally disagree with you.  BUT!    I was there at the big voltage change.  Some of what went away was the frequent  need to jump start someone due to a low battery.  Or push!   Remember those bumper "guards" so many today complain about?   They had a purpose.   

 Yes, a well maintained 6V system is adequate.   Maintaining one is difficult.  Much more so than a 12V. Much less leeway.

 

 I WAS  a LITTLE overboard in my original comment.  I apologize.   I still believe I could have wired it in less than the two years.  

 

  Ben

[Fordy]

8 out of 10  starters I rebuild will spin over fine on 12 but nothing happens on 6. The problem is nearly always solder connections on the armature that have failed. It is a fairly simple fix to thoroughly clean it and resolder the commutator and off they go like new. The other issue on the rest would be a loose terminal post that needs resoldering. No point changing to 12 volts to fix a problem when the actual problem will remain unresolved by said "fix".

Steve

[Frank DuVal]

Ben, I was in college in the 70s and we were still carrying jumper cables because giving/needing a jump was common. Probably due to college students trying to put off investing in an NEW battery! Also roll starting from a slight downhill parking spot was common too! So, more like battery technology has improved over the years, they last longer than three years these days*. 😉 Nothing to do with voltage, except the 12 volt battery can be more % dead and still start the car with smaller engines. And jumper cables can be the typical cheap 10 AWG aluminum.🤣

 

* I had a JC Penny lifetime battery back then and got several replacements before the JC Penny stores were sold to sears and the warranty got to hard to get new battery. By then I could afford another battery!😁

[edinmass]

Here is a few photos of a car I am fixing. It went to three different shops for a 6 to 12 conversion. No one can fix it. Long story short Phil and I got it straightened out.  Only took 37 hours. Everything works now. 
 

 

Edited June 9 by edinmass (see edit history)

[Grimy]

57 minutes ago, edinmass said:

Here is a few photos of a car I am fixing. It went to three different shops for a 6 to 12 conversion. No one can fix it. Long story short Phil and I got it straightened out.  Only took 37 hours. Everything works now. 
 

 

For you, @edinmass a fish-eye lens seems strangely appropriate.....

[Ben Bruce aka First Born]

1 hour ago, Sanjay said:

Is the 12 volt really an upgrade?

One will never know until one tries.

 

  Ben

[edinmass]

19 minutes ago, Grimy said:

For you, @edinmass a fish-eye lens seems strangely appropriate.....

Just an Apple phone…….No special effects.

[Grimy]

17 minutes ago, edinmass said:

Just an Apple phone…….No special effects.

Check your settings--that's at least a 28 mm lens equivalent--or less, rather like real estate agent photos to make a property and its rooms look more expansive than they actually are.  Or perhaps your calibrated eyeballs see things differently.

[Frank DuVal]

There are settings on an Iphone camera? Who Knew? Now I have to go look.....🤣

[lozrocks]

I have converted all of my cars to 12 volt negative ground. I believe it is an upgrade.

6 volt batteries are very expensive in Australia and most people I know don't get very good longevity out of 6 volt batteries.

On 12 volts my car starts easier and I get much better spark.

A 6 volt coil typically only produces 8kv to 15kv. There are some modern 6v coils with outputs up to 20kv. There are many cars out there still running original coils from the 1920s and I doubt that the output voltage is anywhere near spec.

I run a 40kv output 12volt coil and also modern spark plugs.

I converted my 1929 Chrysler in 1985 and the starter motor has never been rebuilt.

[Ben Bruce aka First Born]

1 hour ago, lozrocks said:

I have converted all of my cars to 12 volt negative ground. I believe it is an upgrade.

6 volt batteries are very expensive in Australia and most people I know don't get very good longevity out of 6 volt batteries.

On 12 volts my car starts easier and I get much better spark.

A 6 volt coil typically only produces 8kv to 15kv. There are some modern 6v coils with outputs up to 20kv. There are many cars out there still running original coils from the 1920s and I doubt that the output voltage is anywhere near spec.

I run a 40kv output 12volt coil and also modern spark plugs.

I converted my 1929 Chrysler in 1985 and the starter motor has never been rebuilt.

 

 

  Good for you.   We,  those of us that believe as you and I,  will just have to enjoy our decision!  😁

 

  Ben

[jdome]

I have cars with zero volt Armstrong starters. They originally required 5 dry cell batteries for ignition spark but I have upgraded to 6 volt rechargeable.  After priming,  if necessary, they start on first crank evertime unless a group of people are standing around watching.