Hey all, Looking to convert my 6V '48 Plymouth to a 12V. I know nothing about the electrical field, but not shy of getting dirty and learning. I know I need to change all bulbs and lights. I may need either an alternator or 12V generator. Can anyone help with the process? How do I rebuild my generator to be 12V? What about resistors or runtz to the gauges? Thanks.
I used a single wire alt for my conversion. The only difficult part of the swap was making the bracket and it really wasnt that bad.
If you want to keep a generator, you'll have find a 12v version with it's matching regulator; it will be easier to convert to an alternator. You'll need a dropping resistor or a 6 to 12V gauge regulator for the gauges. If you have turn signals, you'll need a 12V flasher. If you have a fan motor for your heater, that should be changed. Also, if you still have a points distributor, you'll need to install a ballast resistor.
If you decide to go with the generator you will either have to have a 6V on converted or find one from 1956. In 1957 the number of teeth on the flywheel changed. When I did my research on the 12v conversion of the gen. it was around 150. The generator will give you the original look but I went with the alt just in case I have a failure I can get a replacement at any brick and mortar store. (Napa, autozone,advance...) Either way you should add the inline resistor just before the distributor. The points will be fine but you will need to switch to a 12V condinser. I was told the 6V would work but Ive had two fail. Switched to a 12V condinser and have had no issues. I didnt need to add the drop resistor for any gauges, but I did add one for my heater. Ive heard that sometimes you need one for the gauges and sometimes you dont. I did my swap last FEB and I love it. If I think of anything else I'll let you know. Disregard the 56 gen info I was thinking about the 12V Starter. A 6V starter will work fine. If you go looking for a 12V gen it will have a green badge instead of the red that is on the 6V
I converted my '39 Ply years ago... Starter - the 6V starter will handle the 12V no problem, provided its in good condition. I ran 12V on my '39 Ply starter for years. Recently on my '34 Ply the insulation in the windings broke down and shorted out. But that was due to age not voltage and would have happened even on 6V. If the insulation looks suspect you could have the starter rebuilt. Generator vs Alternator - I ran an Alt on my '39 and never liked the way it looked. On my '34 I am running a '61 Ford generator. It was a bolt in swap, all the brackets are the same even the pulleys swapped without a problem. ('34 has wide vee belts) On my '39 Ply I did not use a resistor for the gauges or the heater motor and both worked fine for several years. Ballast resistor on the coil and 12V condenser. Kipp
I can understand swapping in an alternator and a 12v battery and converting. What I'm not sure about is why would you want to convert and use a generator? Is it worth the effort if you still have a generator? I'm sure it will start a bit easier, but I can't think of any other advantage. Posted using the Full Custom H.A.M.B. App!
Generator vs Alternator - The reason Detroit switched is not becuase alternator's can supply more power, electrical power in Watts, than a generator, the reason, as usual, is cost. An alternator that produces the same power as a generator is simpler, lighter, and cheaper. Alternators also have the added advantage of using brushes on slip rings that only carry the field current were as generators use brushes that ride on the commutator, segmented strips of copper, and carry the full output current of the generator. This means that the brushes in an alternator last significantly longer and therefore are less of a maintenance issue. Usually the bushings go out in an alternator before the brushes, this is the opposite of a generator. Even then, the brushes on a generator will last in a daily driver for 5-10 years before needing to be replaced. It is true that a generator's output drops significantly at idle, but who drives around at 600 RPM? Unless a person has a need for a high output alternator, perhaps some 18" woofers with 1000W amps, or an inverter that powers their microwave, a generator will work just as well as an alternator and look period correct. And personally, I think the brightening of the head lights when leaving a stop light is pretty cool, plus it shows you the Gen is working! my vote is: run what the engine came with. I mean a tall deck BBC with a BDS blower, fuel injected, electric fan, etc. would look pretty stupid with a generator. However, a tri-power 409 looks pretty damn cool with the generator hanging out the side of say a 32 Chevy coupe. Reasons for switching to 12V, number one on my list is the ability to see the road at night! 6V bulbs suck. Second, starting is phenomenally better. Third, the ability to use a "modern" (post 1965) FM radio. Kipp
You can always run 2 6 volt batterys in series and tap in between the batterys for any thing you want to keep 6volts.
I'll tell you my experience with that....Back in '75 when my dad rebuilt our '39 Ply he installed a 12V alternator and ran a special battery that had a center tap. The alt, radio and starter ran off the 12V and every thing else ran off the 6V center tap. It worked okay, but for some reason that he never figured out, during regular driving the 6V to 12V cells would get fully charged and the 0 to 6V cells would go dead. So every month or so, we would have to put a 6V charger on the first 3 cells. Finally in '89 I rewired the car and converted it completely to 12V. Does anyone know why this happened? Maybe the idea is good and something else on the car was to blame, or maybe its just a bad idea that for some reason or other doesn't work? Kipp
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