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1954 F100 Pickup: Upgrade to 12V system?

I have what used to be my grandfather’s 1954 F100 pickup. It is not run on a regular basis, and it usually is quite a chore to get started. I keep it on a trickle charger, but it doesn’t always help. It has a 6-volt system, and I am wondering if I should upgrade it to a 12-volt system. What might that cost, and will it de-value the truck?

is the truck stock and what kind of shape is it in?

Unless this is in museum condition, it’ll probably add value, folks convert to 12V all the time just for the reason you mention. I bet there are classic F100 forums where owners could give you step by step instructions.

Leave it at 6 volts. To upgrade you would have to replace all electrical components – bulbs, gauges, generator, voltage regulator, starter, blower, etc. And what’s the point?

If you are having starting trouble, begin with a full tune-up. There are still some old-timey mechanics around who remember how to do this.

Changing to 12V will devalue the truck. Not sure how you do it either. I think the wiring is OK, but it is more involved than just changing 6V for 12V bulbs. Would you go to a 12V generator, or an alternator? What about the gauges, interior lights, dash lights, etc.?

If you want to make this a daily driver, a 12V system would help if you live in a cold winter climate. Me, I’d stick to 6V. I would consider a very light oil 5W-30 if you plan to run it in cooler weather. If you go with such an oil expect it to burn oil, so check the dipstick frequently. In the summer months go back to straight 30W oil which is likely what was called for in that era. The lighter oil will make it much easier on the starter to crank the motor and should make the starting a lot better.

These old trucks have increased in value and “collectivity” a great deal over the last few years. I would not do anything “non-stock” if the truck is still in near original shape. Putting up with the “flaws” of these old trucks is part of the fun of ownership.

I tried to find a 6V '54 F100 on ebay - maybe one in 20. Most all are restored/modified.

How about trying to fix it first.

I’m not familiar with 1954 carbs, but this strikes me as more likely to be a fuel metering problem. Perhaps the acelerator pump is shot (envision a 58 year old diaphragm…), or the high idle cam hasn’t worked since forever, or the gas is draining back into the tank when it’s shut off and the mecyhanical gas pump is losing its prime. There are other possibilitioes, but you get the idea.

Exactly what is it (not) doing when you try to start it? Is there a specific “dance” that helps it start? Is your grandad still with us to offer some input?

There are kits that allow the starter to operate at 12v but the truck remains 6v. It requires 2 6v batteries or an old style hard case battery that has external cell connectors.

If you’re considering redoing the system, I wouldn’t skimp and just replace every wire you see. 60 year old wire probably needs replacing at this point.
There are places out there that will sell you an entire tree of wire you just put in. You’ll probably at least need ballast resistors, a new voltage regulator and alternator. 6V starters tend to work fine on 12V.

Not to be redundant, but wouldn’t it make more sense to first figure out WHY it’s having a hard time starting? The fact that it’s 6V may have nothing to do with the problem.

There’s lots of info on this Ford truck forum on converting, if you end up doing that:“12+volt+conversion”&ref=esp-nav-bar&type=all

But make sure ignition and carb are correct, as noted above. In addition, on 6V systems the electrical connections need to be clean and tight throughout, can make a BIG difference.

You could just install a 6/12 volt battery. This allows the starter to operate on the 12 volt side of the battery while allowing all the vehicles electricals to operate on the 6 volt side of the battery.


I grew up with 6 volt systems. My first car had a 6 volt system. I am certain that your 1954 Ford is a positive ground. My suggestion is to leave the truck at 6 volts. Clean up all the connections-battery cable clamps at the battery and the connections on the other end of the cable. Make certain that the coil polarity is correct. Replace the ignition points and condenser, distributor cap and rotor, spark plugs and wires. You may have to replace the coil–coils sometimes deteriorate with age.
There is no reason that a 6 volt system won’t start a car in cold weather as well as a 12 volt system. In zero degree weather, the school bus that did my school unfortunately always started in the morning and we got to school. If the driver left his bus at school and rode back home with another driver, fortunately the bus always started and we got back home.

I’m also wondering how fresh the gas is. Grandfathers don;t alway drive their old pickups eniough to keep fresh gas in the tank.

I think there’s some stuff to check out here before assuming that a 12VDC conversion will solve the problem.

Do what alot of old Chevy owners used to do,put an 8volt battery in it.Generally the Gen and reg will keep the 8v charged-Kevin