How to jumpstart 6V?

[daveboy]

I took Daisy (my mostly restored '52 1/2 ton) for about a twenty mile ride today. I've only had her for about a month and today was the first time I drove her in the rain. What were they thinking with vacuum-operated wipers anyway? I did discover a few leaks around the windishield/cowl area, and I will address that later. I had to turn on my headlights and yep...wouldn't you know it? I forgot to turn them off when I got home. As luck would have it, I realized my mistake before it was too late and Daisy fired right up. But, that started me thinking...can you jumpstart one of these 6V trucks SAFELY with a 12V battery? I know it is not designed for such, and can't be good for it to do it much. But, in case of emergency, can a friend with a modern 12V vehicle give me a jump without causing damage?

daveboy

[G&R's57GMC]

Your gauges and accessories would be at risk of frying.

The battery could have a problem and may explode.

Time to upgrade to 12v and electric wipers.

The beauty of this is you just need to change bulbs, headlamps, coil, add a ballast resistor,
a voltage drop resistor for the gauges and heater fan.
Add an alternator with a 10 gauge wire to the battery, a volt meter in place of the ammeter. The Starter can handle the 12v and spin the engine faster.
If your wiring is in good shape it will handle 12v just fine because its about twice the gauge larger then what 12v would require.

[daveboy]

Thanks, but it is important to me to keep this truck as original as possible. I will make exceptions for safety, but I really would like to keep the 6V system. It is quirky, but this truck will not be used as a daily driver, so I think I can live with it.

daveboy

[mechanixman]

It's tricky.
What you do, is disconnect everything that is connected to the top of the starter.
Circled blue in the picture.
Leave it all connected. one should be the positive from the battery, the other should be the wire to everything else in the truck. Coil, lights, Gauges. So you connect your jumper cables (from the 12 battery) negative on frame, I like to use the copper ground strap. And the positive to the copper stud. Your starter won't be affected (unless you keep it turning for like 5 minutes). And hopefully, you'll have enough juice in the 6 volt to get spark to the plugs.


I hope that helps,

[_Ogre]

turn everything off and jump start it
done it many times

[Russell Ashley]

Originally Posted by _Ogre

turn everything off and jump start it
done it many times

yep. In the late fifties I worked at a Pure Oil service station and we were often called to jump start cars, mostly still six volt. We carried a 12V battery in the truck and that's what we used on them. Never hurt anything that I remember.

[sweet70beast]

Another option rather than putting an alternator on it you could put a 12v generator and voltage regulator on it so that it looks stock but has a better electrical system and brighter light.

[mknittle]

Originally Posted by sweet70beast

Another option rather than putting an alternator on it you could put a 12v generator and voltage regulator on it so that it looks stock but has a better electrical system and brighter light.

That reminds me Somewhere is my searches I found an alternator that was built to look like a generator for the stock look. I cant remember where though.

[mknittle]

Originally Posted by _Ogre

turn everything off and jump start it
done it many times

yeap me too. I don't miss generators

[mr48chev]

If you made it home I'd just put the charger on it and if you don't have a six volt charger or one that can be switched to six volts it's probably time to get one.

If you have to jump it it is better to jump it to the stud on the starter rather than to the battery though with the negative jumper cable hooked to the ground strap or the block. My grandfather blew up the battery in his 48 one ton jumping it at the battery and was over the battery looking down at it at the time and ended up in the hospital for a couple of days.

As Ogre said earlier turn everything off when you are jumping it as that is where the problems start with the accessories and lights.

Outside of lights that aren't as bright as they could be and not being able to add any 12 V accessories I don't see any other problems with keeping the 6 volt systems. Normally a guy with a six volt rig isn't going to drive it all that far from home base nor does he/she intend to add accessories as they plan to keep them stock just like they came out of the box. If you do make a road trip to a event with the truck it would be prudent to get a spare headlight and some spare bulbs for the tail lights as many parts houses may not have them in stock if you burn one out.

My only real issue with generators either six or twelve volt is that you may have a real hard time finding a replacement or repair parts on road trip to some event that several hundred miles away. Those of us who are on the Hamb will tell you that the biggest number of "broke down on the side of the road need help" threads are from or about guys running generators who have had their generator crap out on a road trip to some big event that is three states away from their home base. If you run one take it into a good generator shop and have it checked out and gone through so it is in top shape so you can hopefully eliminate problems and don't add power draining accessories like big sound systems or halogen headlights that cause the generator to charge at close to it's amp rating for hours on end.

[meter swinger]

I have jumped my dodge a few times, and like OGRE says, i do it with everything off. But i take a 12v battery out of one of my other cars or shut the 12v car off when i jump it, not sure it makes any difference, but makes me feel better. LOL. Never had any issues, but i only have done it a few times.
Posted via Mobile Device

[mechanixman]

Originally Posted by mknittle

That reminds me Somewhere is my searches I found an alternator that was built to look like a generator for the stock look. I cant remember where though.

Here it is!
I got it for $100


The reason I said take the wires off, but leave them connected, was because you still need juice to the coil. If you just leave it turned off and connect the jumper cables, then all you're going to be doing is turning the engine over. Or am I missing something?

[55dude]

When you get tired of the issues with 6V you will do the conversion to 12V.