I recently purchased a 1950 F6 with a flathead V8 in it. It’s in pretty rough shape but who doesn’t like a challenge. There wasn’t a battery in the truck and the cables are also gone. The distributor is missing some parts and I want to order some stuff. What I’m trying to figure out is if this truck is a positive or a negative ground truck? Anyone have a way to tell that I am not aware of?

 

Welcome to FTE! Sounds like a great project.

From the factory it would have been a positive ground, but there is always the slim chance it has been converted.

Are there any part numbers visible on the generator or the voltage regulator?

I would check things like the headlights first. That would be a fairly accurate indicator.

 

Welcome to the forum! Is this truck a COE, as alluded to in your user name? Congrats on your find. Originally the truck would have been 6 volt positive ground. If it were converted to 12v at some time, it would also be changed to negative ground. Since your wiring is gone to the point of not being able to tell, one of the easiest ways to determine would be to pop out a headlight sealed beam and see if it has markings on the back. Usually there's a stamping with brand and voltage.

 

I’ll have to check the generator and see what I can see.

Both the headlights are also gone. Also it is a COE truck.

 

Check the cover of the voltage regulator. Sometimes on the top or bottom of the cover it will tell you the voltage and polarity.

 

I’ll have to check it out on Thursday. That’s my one evening a week I get to work on it lol. Thanks for the info everyone.

 

Does your truck have a heater? Although not definitive, a 12v conversion may have included a large resistor for a voltage drop to the heater motor. It was an easier mod and routinely done back in the day rather than changing out the blower motor.

Given how boned out the truck is, electrically, it may be as good a time as any to set it up for 12v, if for no other reason than convenience.

 

that’s a good point. I don’t know the condition of the remaining electrical components so now may be a good time to switch it all over.

 

The engineers back in the day knew what they were doing. A well maintained 6V system is just as good as a well maintained 12V system. I feel that those who boast "performance improvements" with their new 12V systems with new battery, charging apparatuses, new wires etc are comparing to a rundown 6V system. The 6V system would have the same improvements if all the same items were refreshed (and probably for a little less $$$ and less frustration and you get the bonus of originality too)...

I have many numerous 6V systems and don't have any issues or qualms with them, including in my big trucks just like yours.

 

i don’t really have a preference as to 6 or 12 volt. I just assumed the 12 volt stuff would be less expensive. Guess I shouldn’t assume lol.

 

100% Correct! Just this last summer a friend of mine was having what he described as many electrical issues with his '50 F-3. Everyone was telling him just to convert to 12 volts. He decided instead to try an 8 volt battery. The one problem though was he needed his voltage regulator re-adjusted. He asked me to help him out with that. If we did the 6 volt to 8 volt conversion, I wanted to try to find another 6 volt regulator that was good that we would try to adjust to 8 volts, so if he wanted, he could just swap out the battery and regulator to go back to 6 volts again. The day I got to his shop, the first thing we did was look at his battery cables. They both showed corrosion around the area where the battery post connectors were crimped on the cables. Plus they were #4 gauge. I told him before we mess around with any voltage regulator adjustments, let's try going to NAPA and have them build some 1/0 or 2/0 cables. We put his battery on a charger, and went into town to get the cables made. We changed out the battery cables as well as the solenoid relay to starter cable. After changing the cables with a topped off battery, the truck starts like a dream. Just a bump on the starter button and she's running. We knew it would make an improvement, but couldn't believe the end result. Before he was always hesitant about driving his truck anywhere wondering where a jump start would come from. Now he is driving it all over town, even taking his wife out for ice cream on Saturday nights with no more starting problems. He was so impressed he had new battery cables made up for all his 6 volt tractors and cleared up starting issues with those. And he returned his 8 volt battery. Long story I know. Just saying I agree with Bmoran. There is really no reason a 6 volt system won't work good as long as you have good heavy battery cables, ground grounds, and tight clean connections. All this is true as long as you don't want to add 12 volt accessories.

 

if the parts are the same or less expensive I don’t mind keeping it 6 volt. I just need to figure out which one goes to ground and I’m set. I’ll try and find out this Thursday.

 

Agreed....

 

The main reason for switching to 12 volt would be adding accessories; modern radio, heated seats, AC, etc. And your headlights might be a little brighter, but not significantly. If that doesn’t interest you it may not be worth the hassle.

 

If the truck has any tail lights or signal lights left, you may get a clue there. For example, an 1154 bulb is 6 volt while an 1157 is 12 volt......