Packard Forum Index » Post-War (1946-54)

Quote:

I know lots have done it and still are. Starters we used are pretty robust winding wise so not too much an issue. IMHO, main reason not to routinely do it are either here or on the AACA Packard website. Some pictures a member posted showing an exploded Bendix and chipped and broken teeth on ring gear caused by the 12v slamming things into mesh. That expensive mess should give pause for thought.

With 12 volts applied to a 6 volt starter there are 2 potential problems. The starter will spin faster and the temperature inside the starter windings will go up faster. Usually spinning faster will fire the engine quickly and temperature is not an issue. If you have difficulty starting and do not let the starter cool that could damage the windings.

The higher starter speed could possibly damage the teeth on the flywheel or the bendix by impact loading.

Many people have successfully changed from 6 volt to 12 volt electrical systems and never touched the starter.

You did it correctly. It is not a good idea to leave the battery connected to 12 volts for long in fact it could blow the battery up. The right way is to have one person connect the jumper cable as the other person starts the car, then disconnect immediately.

Or, disconnect one battery cable and leave it out of the circuit, then stick the cable back on quickly once it starts.

By the way batteries that are not used very much are prone to sulfation especially 6 volt batteries. if your battery is sulfated you can revive it by adding EDTA and giving it a slow charge. I have done this on batteries that were dead as a door nail and over 10 years old, and they came back to life.

I replaced the old battery with a new one I picked up at a local CarQuest outlet. It was basically this model:

batterygiant.com/Product/3EH-925

CarQuest charged me $136 for the new battery but gave me $12 for the old core, so the net to me (before sales tax) was $124, which I thought was fair.

Once installed, the new battery performed very well and I had no trouble firing up the engine. By a happy coincidence my mechanic, Jerry, was also at the CarQuest store. He assisted me in installing the new battery (out in the store's parking lot) and then pulled out his voltmeter to do a quick check on the electrical system. He announced everything was working satisfactorily. I was a little nervous I'd adversely affected the generator or voltage regulator, or whatever, with the 12-volt jump, but Jerry assured me all was well. He did a quick check on the old battery and declared it had a bad cell.

Aside from needing a jump, the whole battery-change process was about as painless as could be. Less than 24 hours after the old battery let me down I have a shiny new one installed in the car and I'm now back on the road in style!

All the best and thanks to everyone for the advice.

Mark

For what it is worth-Tractor Supply sells these batteries for $89-in addition there are coupons available on line for a $5 discount.

On a related issue - has anyone seen a 6 volt jump starter? I have been looking for one and have only seen 12 volt machines.

has anyone seen a 6 volt jump starter

Never seen one, and never heard of one. As long as you follow the correct procedure you can use the 12-volt to jump a 6-volt so there really isn't any market for one.

I wish the originator had worded the title a little differently. I was real excited for about 15 seconds.

Not a problem. I recently had to get a 12v jump. I made sure I didn't have any lights on (including the brake lights) nor any accessories. The 12v jump was removed ASAP. There was no damage.

Sears / Diehard makes a 6V / 12V jump starter. Harbor Freight makes one very similar too but it's a little less expensive.

harborfreight.com/612v-battery-charger-starter-67855.html