Question: keeping 12v but need 6 volts to run gauges

[Guest Jonny88]

Does anybody know how to keep 12 volts for starting but use 6 volt to run all the gauges. My 51 Olds 88 would never start that big V8 with a 6 volt system, but I need all my gauges which currently do not work. I have heard of resistors that are used to step down the current, but dont know any of the math or anything else. Is there a product that I could buy to make this conversion simple and cost effective? Thanks

Jon

[Guest Jim_Edwards]

First of all Jon there is no good reason a 6V starter should not crank the engine in your car. 6V systems were used by Olds through 1955 and those engine displacements were greater than the engine in your car and had higher compression. With that said it will be a whole lot easier to use a 6V starter than to try and work around the issue given the nature of all the chassis circuitry involved. Ain't just the instruments!

But if you must you can use a DC/DC Converter Regulator 12V Step down to 6V.

You can find them on ebay for under $50, but be prepared to have multiple issues that will involve the main feed to the dash, the ignition switch, and ultimately the fuse block.

DC/DC Converter Regulator 12V/24V Step down to 6V ?100W | eBay

Jim

[A. Ballard 35R]

Jon, you might want to read the seperate thread on switching from 6v to 12v. As mentioned above and on the other thread, the real question is why the change to 12v. You are inviting unneeded problems by changing. Good luck.

[Guest Jonny88]

You both are right, I have been wanting to change it back to 6 volt to avoid the headache of all the other electrical problems that would arise. Others have said to hell with the 6 volt, but it would be cheaper and less of a pain in the long run, I already have a 6v generator AC Delco, will need a regulator I guessing as well. Is there anything else that I am missing?

Thanks guys.

Jon

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1951 Oldsmobile Super 88

[PONTIAC1953]

hi jonny88 and jim edwards, olds rocket V8's were 6 volts from 1949 to 1952, not 1955 jim. there's nothing wrong with the 6 volt system, jonny88, make sure the positive battery cable is number zero, or number two gauge wire, and the same size for the negative cable or get the braided wire strap type cable for the negative side. make sure the connections are all real clean and tight. places like lectric limited and fusick's can charge a pretty high price for cables. find a local automotive electrical shop and ask if they make battery cables to order. you might check the local napa store too. charles coker, 1953 pontiac tech advisor.

[Guest rocket49]

Everything those guys said is true but your main cause may be the bushings are worn in your starter. Most rebuild places don't have those old bushings any more and don't replace them. there are other causes that could be your problem. I'm not much at typing so call me and we discuss your options. Skip 248-778-7129

[Guest Jonny88]

Thanks guys for your help this has really opened my eyes to what I will need to do to make this old gal work again in terms of electrical. It truly is a mess of what I have to deal with now, I figure it would be easy to just restore the car back to 6volt that way I can use my gauges and all other accessories within the car, something I am looking forward to doing. Right now the car functions ok. The only electrical that works is the starter, headlights, bright and dim switch, with the light showing on the speedometer, strange, and one parking light and one tail light. The right turn signal makes the clicking noise but does not light up interior or exterior. The left turn signal does not work at all, dash lights do not work at all, radio, cigarette lighter, glove box and interior light do not work, brake lights do not work. What A mess, but maybe switching back will help, if everything is not burnt up already.

Jon

[Guest Jim_Edwards]

hi jonny88 and jim edwards, olds rocket V8's were 6 volts from 1949 to 1952, not 1955 jim. there's nothing wrong with the 6 volt system, jonny88, make sure the positive battery cable is number zero, or number two gauge wire, and the same size for the negative cable or get the braided wire strap type cable for the negative side. make sure the connections are all real clean and tight. places like lectric limited and fusick's can charge a pretty high price for cables. find a local automotive electrical shop and ask if they make battery cables to order. you might check the local napa store too. charles coker, 1953 pontiac tech advisor.

Yup Charles you are correct about the Olds year of transition from 6V to 12V. For whatever reason the various GM divisions were not in lockstep with respect to the year of transition which I had never paid a lot of attention to not having personally owned a 6V car since 1959. Olds and Caddy were apparently the first, followed by Buick, and then Pontiac and Chevy, except for Vettes being a year earlier than other Chevy products.

Jim

[Guest Bob Call]

Jon

Sounds like the 12V has fried parts of the electrical system or maybe whoever put in the 12V battery disconnect a lot of stuff to prevent fires. Get the 6V starter rebuilt, get proper 6V primary battery cables and go from there. You might have to replace the complete wiring harness. Probably not a bad idea for 60 year old wiring.

[d2_willys]

If you decide to go with a 12V system you might want to remember that the only year starter drive that will work for you is 1953. In 1954 Olds changed the tooth count on their flywheels, so the later starter drives will not work for you.