View Full Version : Electrical: Damage by putting 12 volt battery on 6 volt system.

08-24-2017, 08:18 PM
Joe and I went to look at a 2R truck today. When the owner got ready to start it, he used a 12 volt battery and hooked it up negative ground. :o When I told him that was not right, he said when he bought the truck that was how the seller loaded it on his trailer and that he has driven it around his property like that. What parts may have been damaged? I did not see any voltage drops or 12 volt bulbs. The bulbs are no big deal, but did he fry the gas gauge or anything else?
The truck had this device on the firewall, but I think it was some kind of adjustable voltage regulator. The printing was faded.

08-24-2017, 09:12 PM
Short term probably no problems if lights are off. I don't think the gauges would be fried, but I wouldn't run it that way for more than a few minutes. On the other hand if the gauges are already fried no further damage will probably occur. If the generator is functional it may need to be flashed when a 6 volt pos grounded battery is installed.

08-24-2017, 09:40 PM
That would be good. We were thinking of making an offer on the truck and wondered what we might be getting. The seller is not at all familiar with Studebakers although he has other collector vehicles. He knows a lot more about them now that we visited. :)

08-24-2017, 09:51 PM
It's quite possible that the fuel and temperature gauges have been damaged, but the oil pressure gauge is mechanical and should be OK. The points and the coil will take a beating, as will the generator and voltage regulator. But those are small things compared to the rest of the truck.

If he has driven it fast enough to engage the overdrive, the relay and the solenoid could be damaged. Since the vast majority of great unwashed masses do not understand overdrive and leave the handle pulled out, the electrical overdrive components may be OK.

Either way, the guy deserves a dope slap. :)

08-24-2017, 10:30 PM
I don't think he ever drove it fast enough for overdrive. When I originally asked him, over the phone, if the truck had overdrive he didn't know, but it obviously does. The truck has a super nice body so I hope we can work out a deal.

08-25-2017, 04:51 AM
The generator will need to be polarized again when you'll hook up correctly a new battery. Gauges and voltage regulator are likely shot. If the ignition coil shows oïl leaks, it has boiled and might not be trustworthy anymore

08-25-2017, 08:04 AM
just for a laugh.... its amazing how many people tell me to get OD you "pull out" the handle.... did the OD systems ever operate that way..

08-25-2017, 10:20 AM
Joe would have probably made a cash offer on the truck yesterday except for some nits we didn't expect. The previous owner had someone start sanding the truck because he didn't like the original color. They removed the glass and regulators from the doors as well as the headlight buckets and door handles. The man passed away and the parts were lost. We can source all the missing parts, but it is a consideration to the value. The truck has an amazingly solid and straight body, but the asking price is steep. It is a shame that the truck was ever sanded down. :(

08-25-2017, 03:19 PM
For what it's worth, in my teenage years (around 1957-1959) I worked in a gas station in Chicago and had the job of jump starting a lot of cars during Chicago's wonderful winters. I ALWAYS carried ONLY a 12 volt battery and because of the time period, I had to start a lot of 6 volt cars. In my ignorance I didn't give much thought to any damage I might cause, but I was VERY careful to jump positive to positive and negative to negative. I always made sure the car would keep running before I disconnected the cables (usually a couple of minutes). I never had a customer come back to the gas station and complain that something electrical had failed. Just sayin'.

08-25-2017, 04:47 PM
I have done the same as Howard to MANY 6 Volt Cars jumping with 12 volts over the years, but you ALWAYS connect Positive to Positive, the Starter gets a really good spin and with everything turned off that could be and no damage was done for a quick "Start", NOT a longer than a 30 Sec. or a minute run cycle though.

That reminds me of "One Time" (NOT at Bandcamp, if you saw the Movie) where I could not get close enough to make Both Jumper Cables reach, so I connected them together, put them on the Negative Terminals of a 6 Volt Positive ground Car and a 12 Volt Negative running car, and ran the bumpers together! :ohmy:

Worked like a charm, the things you do in your youth! :lol:

08-25-2017, 09:03 PM
I have jumped 6 volt vehicles with a 12 volt battery. The thing that worried me was finding that he was hooking it up backwards and had driven it that way. Lucky for him that the brakes weren't good enough for a long drive.

08-26-2017, 01:44 AM
Hooking the battery up backwards was not as damaging as running the truck on 12 volts.

Jumping a 6 volt vehicle with 12 volts is less damaging than installing/operating a 12 volt battery.

But we are probably making too big a deal out of it. What's done is done. The electrical parts are more easily replaced than other things. Too bad he sanded the paint and then left it. That deserves another, even more vigorously applied dope slap. :) Or maybe just buy the truck to get it away from someone who is hell bent on making it worse. I've done that with a few cars.

08-26-2017, 09:16 AM
Too bad he sanded the paint and then left it. That deserves another, even more vigorously applied dope slap. :) Or maybe just buy the truck to get it away from someone who is hell bent on making it worse. I've done that with a few cars.

Too late to slap the guy who had it sanded. The current owner is not at fault. He bought the truck because of its superior condition to the Chevy pickup he is working on, but decided it needs to be passed on to someone else. He also has a couple of Model A cars so he is a car guy, just not a Studebaker guy.
It was interesting to hear him praise the modern features he discovered on the Studebaker. He is currently rebuilding his Chevy bed to prepare it for new wood and remarked on the Studebaker's steel floor and double walls. He also likes the step inside the doors. He had not been aware of these features and was impressed.