12V to 6V... Sorta? Feasibility Questions...

OK, so it has become obviously evident that I'm going to need to do something about my piss-poor 6V system. I looked into various threads on the HAMB about 6V to 12V conversions, and it seems like it's a pretty straight-forward and rather easy thing to do. But from what I've seen, I'm looking at right around $150 to $200. Me, being a cheap sonofabitch out of other financial obligations, started to ponder the situation. Here's what I came up with...

Running a '53 Chevy 235 with the stock 6V system. Keep in mind I just spent about $200 refurbishing my 6V system in order to make the car run. I wasn't about to spend the money on the 12V conversion without knowing whether or not the inline 6 was going to run, and while I didn't spend $200 up front, it nickel and dimed me up to that amount.

MY thoughts are, why couldn't I mount a 12V alternator as one would do with a 12V conversion and then run a 12V to 6V resistor between the alternator and the (new) 6V battery instead? I'm thinking about a resistor such as eBay item numbers 140633076371 or 290677983874. The tail lights, dash lights, blower motor, and fuel gauge could all stay on the 6V side being fed by the battery and I wouldn't need to put individual resistors before each of them as I would in a full conversion. Then I could split off from the 12V (alternator) side and run power to my (as of yet non-existent) radio and headlights. I would have the bright headlights that 12V offers, a radio (yipppieeeee!), and anything else I wanted to run 12V. I would have the reliability of a 12V alternator as a charging system (versus the crappy 6V generator) while the rest of the system could stay 6V, which seems to be working just fine. Not to mention, I wouldn't ever have to worry about running my battery dead from leaving my headlights on since they will only get power when the engine is running. I can do this "conversion" for less than fifty bucks.

Does this sound like a feasible semi-conversion?

 

Why don't you just repair the grounds for your 6v headlights, that is usually the problem. The get yourself an inverter when you decide to out that yet non existant radio in.

You are looking for a 20 dollar solution to a 10 cent problem.

 

You can buy a 6-volt regulator for the internally regulated Delco 10-SI alternators. I've retrofitted several of them, and it's great. Good output at idle, keeps the battery fully charged, and would probably cost you $19.95. You can also get an 8-volt version if you want, or if you want to go military you can get a 24-volt version. See the link below, one of many sources for these......

http://www.ebay.com/itm/Delco-10SI-...-Regulator-1-Wire-Self-Exciting-/200679425550

 

Beaner! Hey buddy! No, actually the big problem is that the generator isn't charging the battery. My headlights aren't even hooked up at the moment, so they are a NON-issue. All the wires were cut and the buckets were empty when I got the car. In the back seat were two new Sylvania bulbs still boxed, but I'd bet anything they're modern 12V bulbs. I threw them into the sockets just to de-ugly the car for the time being (so my wife wouldn't go ballistic at me for dragging home another beater project that I have high-hopes of turning into something special). The REAL issue is that the generator isn't putting out any voltage, even at 2000rpm, which is supposed to be when it's actually doing the charging. SOOOO, $160 generator to repair a 6V charging problem, OR a $24 alternator, some shop time to fab up some brackets, and another $15 for a 12V to 6V resistor to keep the new $80 battery I've already got, charged up. You with me dude? I knew I could count on hearing from you, Beans. And while I do respect and appreciate your input, I don't think I appropriately described what the root problem was in my OP.

 

That's interesting. Never knew they existed. Only thing is, it would end up being the equivalent of running a 6V generator. No bright 12V headlights and no radio. I gotta have my radio. If I can't cruise and listen to ZZ, The Who, AC/DC, Ministry, or the rest of the eclectic genres of CDs I like to hear when I'm driving, well, I'd rather take the bus.

 

Not much really goes wrong with the old gennies. Usually a set of brushes will cure one maybe clean up the contact end of the armerture. A voltage regulator is a little pricey like up into the 12 dollar range.

I got to ask because I don't remember is your Chevy positive ground or was that only Fords. That in the end could up be a headach changing over to a 12V/2 system.

Ebbspeed has come up with an easy solution for you. Then you have no need to try and buy a resistor stout enough to handle the battery charging.

Your headlights should say 12v on them somewhere if they are.

 

Nope, not a positive ground. As for the headlights, I just never bothered to check. The gaping empty sockets made the car look a lot worse than it was, so before it even left the spot I found it I made it a point to gussie it up a little. My wife wouldn't have been able to look past the blank front end and see all the positive points. Chicks...

Wondering if maybe the voltage regulator might be shot? Or even hooked up incorrectly? I haven't messed with any wiring other than to remove the generator, check the brushes for wear/binding, and clean up the contact end. I put it all back in the same way it came out, so I dunno. With the car running I'm only getting a little less than 1V reading, and it only goes up a half volt or so when you rev the engine. These 6V systems are a totally new thing to me, so please forgive my ignorance. I'm used to messing with OT 60-something cars.

 

you could pick up the 8 volt version of the alternator piece, ( or put in new brushes )& slip in an 8 volt battery, & leave all the 6 volt stuff alone... my Nash currently has the fully stock 6 volt system, with a properly functioning 6 volt genny & an 8 volt battery I picked up from NAPA... car starts like it's been converted to 12 Volt, & the 6 volt headlights on 8 volts are as bright as any 12 volt light... "they say" you'll go through bulbs faster... I replace 1 - 2 bulbs every 2000 or so miles

 

The 6 volt alternator solution suggested bu Ebbsspeed is the more sensible cost effective way to go.....I have a close friend who operates a professional starter/generator/alternator shop and he has done many of these for his Ag customers (old tractors etc.) and it works great. partially solve the 6 volt current problem as the alternator charges at very low rpm, unlike the generator.

Then, when you ARE ready to go farther with the 12v upgrades, all you have to do is change the internal regulator on the alternator to 12v and you're home!

But Beaner is correct also, in that most (not all) non functioning generators respond to a cleanup and new brushes..........

Your call, but it will be hard to come up with a better solution than these guys have recommended.

edit: posts made while I was typing. 8 volt batteries are a common recommendation, but the same pro I mentioned above can give you a LOT of good reasons why they are not such a great idea, IN SPITE of all the "works great for me!" testimonials. Again, your call

Ray

 

Pretty sure all cars were pos ground untill about 55...

 

No sir. Not Chevy. GMC, yes (I believe). But I'm 99.999% sure Chevy was a negative ground originally.

 

I guess what I'm asking is, by the original plan in my first post, is there any reason it would not work?

 

Ford and Mopar were pos ground until switching to 12v systems in 1956. All the GM vehicles I have ever had first hand experience with were negative ground, regardless of 6 v or 12v systems.

Ray

 

You may need to polarize the generator. Just run a jumper wire from the positive side of the battery to the ARM. post on the generator. Just touch it to the post, don`t leave it on more than a half second. You`re only going to re-magnetize the armature. This may solve your problem.

 

Why in the world would you want to "waste" all that energy by dissipating it through a heat producing resistor and loading the alternator for the privilege?????????

Besides which, 12v systems operate on half the amperage of a 12v system, so it seems to me, and I am admittedly not an electrical engineer, trying to double the amps while you are halving the voltage, just does not make sense in any way, shape or form.

As an old friend of mine used to say "blow your nose and get that idea out of your head!"

Ray

 

Bite the bullet and go full 12V. It was the best thing I ever did. Bright headlights and do not forget brighter tail lights that people can actually see and WAY easier starting. Not to mention the radio you need/want. An alternator is made to keep up a charged battery not power headlights and radios and will not last if you do what you are thinking. But if you insist, a 12V generator might work for your plan, look on that auction site they were common in the mid 50's, and should fit wher your 6V version is with little modification. But this plan may nickel and dime you to the $200 you would have spent just to do it right the first time.

 

Won't work. Those resistors are ballast resistors rated at about 3 ohms, which is approximately the same as the internal resistance of an ignition coil. In order for a series resistor to act as a voltage divider reducing the voltage by half, it needs to be the same resistance as the other component it is in series with. Even if you could determine the proper value, it would be a horrible way to accomplish your goal, and would not give you a predictable voltage across your battery.

 

Ray
My experience with 8V is that the gauges never seems to work right. it could have been that the reason it was made 8V is nothing ever worked right in the first place.


Ragtop,
Back in the early '70s when I first moved to Missouri it got really cold around here, like Minnesota cold. A lot of the old timers were driving 6V cars and to get them started in the winter they would have a second battery wired in that they could switch on ( some with a disconnect in the trunk). When it ws a hard starting morning they would connect the second battery to throw 12V to it. The starter doesn't care how much zot it gets as long as you don't crank it forever.

Just another 6V trick while we are talking.

OH and while I am thinking about it, you can open the voltage regulater and look at it. If the points are not stuck or the coils are not burnt up it should work. Sometimes the points will be burnt and need filing to make them function properly.

Anyway a voltage regulator isn't an expensive part to replace or I found a good Echlin one in the garage yesterday while I was cleaning up I'll look and see if it is 6V if you need me to.

 

If I'm reading this correctly, and some on here say I can't read, you want to avoid buying a generator but will buy an alternator. Given the parameters and requirements you list, use the 12v alternator across 2 6v batteries in series. You will have 2 6 volt sources and one 12v power source charged by a 12v alternator. No resistors required.

 

If it doesn´t charge on lower rpm I would take a look at the regulator, you can adjust when it should start to charge the battery.

Attatched a pdf about adjusting Delco Voltage Regulators, hope it helps.

 

Mr Nilsson,
Now that is just cool. I learned all that stuff by fiddleing around with them and never knew that there were instructions for that.

Everyone should take a quick look at that it even has a correct wireing diagram.

You don't mind if I steal that do you? be pretty handy when I am trying to explain that to someone.

 

You mean series.

 

Yes, thank you. Glad somebody watches over the old ones.

It should be series.

 

Hell, I'm 67...I just had a non-senior moment.

 

No problem Pork'n'Beaner, I've stole it too.
I also learned to adjust them by trail & error, but it would have been a heck of a lot easier if I had this Delco bulletin then...
Now I swear by generators and regulators, I would never replace them with a alternator.

 

Grrrrr.......There's nothing wrong with a six volt car...Only not knowing how to fix one...

Take the generator to a shop that knows what they are doing. Have the armature turned, new brushes and new rear bushings put in, It'll start just as good as any 12 volt. Those 6 volt cars have been started in below zero weather since Henry and Louis made cars.

As far as having bright lights. The 6 volt lights are just as bright as 12 volt ones. Front and Rear....What to you want to do, light up the road 2 miles ahead??? Get someone that has a GOOD 6 volt system and battery and someone with a 12 volt system, go out some night and compare for yourself.......


All the above will save yourself a lot of grief and money trying to undo what the automotive engineers know about, how to make them run.


If you want tunes, get a Blaupunkt radio that was for the Mercedes, Porsche, Jag's and many others. The later ones are all transistor, There's a switch on the back you can change them from 6 to 12 volt or visa versa, also you can change them from Neg to Pos ground or visa versa. AND if that ain't good enough for you, there's a place on the back of most of them, that you can get an adapter, readily available on the U Know Where site, to plug in your Ipod. (It works great in my 6 volt Oldsmobile) and as a added attraction, I can get short wave radio on the Blaupunkt I have.


HellRaiser

 

cheapest way; fix the charging problem and buy a portable radio.
i always advise my customers to fix the six unless the car needs two of the big ticket items only in example; a battery/generator or voltage regulator [some times expensive]/generator etc. if the car needs a bunch of bulbs anyway your half way there.

 

Sir, THAT ALONE may have just saved me a bunch of money I really don't have in the account to spend right now. The service bulletin has the correct wiring diagram AND how to adjust the voltage regulator. If I can get the 6V system to charge for the time being, I can at least scratch together some $$$ to do the full 12V conversion in the future. THANK YOU.

And thank you everyone else for all your suggestions. I'm learning a lot through your posts in this thread!

 

Yep...ya better git'er fixed. Cause sitting out in a cornfield with your gal, with the motor not running, playing that ole tube radio, will sure run down the battery, and it won't start.

Sure is embarrassing to have to get a hold of her folks, and tell him where your car is, and why you couldn't get her home on time.


HellRaiser