Jumping a six volt battery with 12

[Allis chalmers 6]

I read somewhere where a six volt starter can be safely turned over with 12 volts by hooking jumper cvables up in a certain way to bypass the battery. Anyway I have a 1941 dodge 4door sedan and I want to fire it up but 6 volts just aint cranckin it over like it should. Any ideas

 

[Goose]

I used to have a '48 Dodge farm truck with a 6 volt system and it sat around quite a bit when I wasn't harvesting or hauling livestock. Sometimes I would start it by hooking jumper cables to a 12 volt pickup and holding the positve cable directly onto the lug on the starter motor on the Dodge just long enough for it to start. I mention this, but I refuse to take responsibility for any negative outcomes from anyone else who tries it.

J.C. Whitney sold a special solenoid wherein you could install 2 six volt batteries and wire them through the solenoid. The batteries would run in paralell at 6 volts normally, but when starting they would switch to series and shoot 12 volts to the starter. I put one of these on the truck and it worked great, as long as it lasted. After about a year it quit working. If I still owned the truck, I would have converted it to 12 volts by now.

BTW, I was the fourth owner of the truck and I lived about 4 miles from the original owner. When I sold the truck on an auction, the original owner bought it back.

 

[Ken Crisman]

Just set the 12 v next to your vehicle . Now hook the cables to the 12 v as normal but on the 6 v system ya hook the pos to ground & touch the starter stud with the neg clamp . Be sure its out of gear tho & the key is on .

 

[Jeff-oh]

Make sure you line Pos to pos. and Neg to negative. and as said just touch the leads to turn it over. Do not clamp the last one down.

 

[JT]

Actually this is the correct way to jump, but I would put the correct cable on the starter lug, then put the other cable to ground. By doing that, you do not arc the starter bolt and posibly mess up the threads for getting the nut off later.

 

[Spritzer]

Used to have a '50 Dodge car I restored. Installed an aux. 12-volt system so I could run the AC, AM-FM radio, and the starter. Worked for years that way. I have also jumped a 6-V battery with a 12-V, but do it only while starter is being used. Shouldn't hurt. How about batt. chargers that can deliver 70 amps while starter is cranking? Same difference.