Have you ever needed to jump off a 6 volt truck and had nothing but 12 volt truck and cars around? I just had that problem recently when my 1953 GMC truck battery went dead. Is there a device out there or some way to to jump off a 6 volt GMC truck with a newer 12 volt car or truck without risk to the 6 volt electrical or risk to the battery? Thanks.
It's been a long time, maybe 37 or 38 years ago I purchased a 41 Chevy Master Deluxe that hadn't run in quite a while. If I'm not mistaken I jumped it off with my 12 volt car. We drove it home and everything worked just fine from that on. Ken
It works; quite well in fact. Just make sure all the lights and radio are turned OFF. Ask me how I know.
You can do it. But if you crank on it very long the caps on the six volt will go very, very high into the air. Also will make an exploding noise. Ask me howmI know.
It works, just don't crank it for too long, short bursts! Had to do it all the time with my 53 Chevy, until I purchased an Optima Red top battery. I cannot say enough good things about them.
A friend of mine actually had the whole top of the 6 volt battery go high into the air covering him with acid . Nothing got in his eyes and fortunately there was a hose handy
It takes two people, one guy turns off everything in the dead car, the other guy hooks the jumpers for only a few seconds. If the dead car fails to start quickly , push it.
I've done it before. The car cranks very fast and started immediately. If it doesn't start right away, you may have other problems.
A friend had a 1954 Ford (6v positive ground) that we jumped with 12v cars quite often. we were careful to hook the cables up correctly, and never hooked both cables directly to the 6v battery. We would hook up everything except the positive connection to his car until his was ready to crank it then we would connect the positive cable to his engine block and disconnect as soon as it started. The only problem we had was the one time the bumpers accidentally touched while we had the cables hooked up -- sparks!
The starter almost "doesn't care" about voltage, it's amps that they like. As has been said, turn EVERYTHING else off. The safest way, again as mentioned, is to use 2 people. The one in the car should begin cranking then the one at the battery attach the cable. Yes, it makes a spark. Better off being at the 12V battery to make the hook up and that car/truck running. The spark at initial clamping will be much less. Why be cranking 1st before hook up? Because the starter draw will lessen the voltage to the rest of the car/truck and provide a modicum of "protection" to the 6V items that will be in play during the starting procedure. Just be careful, and especially careful of the sparks near a battery. Maintenance free 12V are fairly safe in that regard.
I always went directly to the starter connection if you can reach it! two people works best, have one guy engage the starter as normal, then touch the twelve volts to the starter. ( have the hot side hooked to the starter before hand and attach the ground to start ) Gary
I used to do it myself - the early Ford starter relays had a button on the bottom to manually engage the starter relay contacts. I could hook the battery up, push the button, engine fired, release the button & disconnect the jumper cables... As mentioned, turn everything else off and be quick about it. It works fine. The challenge becomes when there's an underlying problem that is causing the car not to start and the battery is dead because you killed it trying to start the car with no fuel/air/ignition - 12V won't fix that and you're likely to spin the engine over and over trying to get it fired up....so, check the basics first.
Always hook up the 6 volt battery first, then hook to the 12 volt last, with 12 volt vehicle not running, use caution I have seen the 6 volt battery explode when hooking to the 6 volt, after cables hooked to 12 volt
Bad idea. Better idea: Charge the 6 volt battery from the 12 volt with a light bulb in series with the 12 volt source to control the current. An old sealed beam 12 volt with one bad side works great, save one for that purpose. or really any 12v bulb will do if it's big enough you don't sit there forever. Solder some zip cord to either good terminal and use the jumper cables on the other side. Do not leave it on there unattended. When the battery gets to about 6.8 volts take it off. Sears Roebuck used to sell a "Miracle Battery Charger" that was good for 6, 8, 12 or 24 volt batteries. You had to unhook both cables from the battery to the vehicle, hook it up, plug it in....It was just a diode and a 40 watt appliance bulb in series with the 120 volt plug. It worked until you didn't unhook both the cables and hooked it up to the car. Then you burned out every bulb in the car or started the charger on fire, depending. Or shocked the living hell out of anyone who touched the car.
My battery charger has a selection which is 12 volt, low amps but is also a 6 volt quick start. Just used it a few weeks ago to start up the 41 which had been sitting for a year. But before I charged the battery, I checked the battery water level and added some that was needed. I also didn't crank it for long. Maybe 3 times and stop and then 3 times again. Too much current at once and the battery water will boil so as a precaution, don't let anyone stand next to the battery while you are trying to start the car.
2 methods. #1 Disconnect the ground cable of the 6 volt battery. Make sure all lights, radio etc are shut off in the 6V car. Connect 12V battery, start car, take jumper cable off ground and quickly stick the 6V cable back on before car stalls out. #2 This takes 2 people. Get set by connecting jumper cables except leave off the ground from the 6V car. Have one person turn key while second person touches cable to ground. As soon as motor starts, take off jumper cables.In other words cables are connected only while starter is turning. If car does not start within 30 seconds stop. Have used both these methods with success and never blew a battery. But will cover battery with rags just in case.
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