The Stovebolt Site Forums The Shop Area The Electrical Bay Ground strap help needed

I'm restoring a 46 1/2 t Chevy. The previous owner had jury rigged a 12 volt system. Just enough to run up and down the road, occasionally. The battery was mounted n the firewall.

I'm going back to 6 volt and moving the battery under the floor board. According to Jim Carter, I need two ground cables. My question is: what guage and where do these mount?

One to the engine, and one to the frame?

Ignore the original cable routing, unless you're building a 100-point show truck. Run a long ground cable from the negative post of the battery to a bolt at the bellhousing near the starter, or to one of the starter attaching bolts. Make sure the cable is at least a #0 diameter. Bigger is always better. If you can acquire welding cable instead of battery cable, so much the better. Hundreds of strands of very fine wire like a welding cable will carry current much better than the relatively coarse stranded cable normally used for batteries. Run the same size cable from the positive battery post to the switch on top of the starter.

For grounding accessories such as headlights, tail lights, and other frame or body mounted electrical parts, run a #4 or #6 wire from the frame to the engine. Connect another one from the frame to the cab, and maybe one from the frame to the bed would also be a good idea. It's just about impossible to have too many grounds!
Jerry

I too would run a large ground directly to the starter bolt from battery.
Make it real easy for those pesky electrons to get there and just as easy to find their way home.

I agree with that routing and it really helps. The other strap should go from the bell housing to the frame. With this arrangement it wouldn't be counted on to carry the starter current. It usually is made of the flat braided conductor.

I overdo everything with my 6v truck battery cables and grounding straps.

00 gauge cables from/to battery:
- positive to starter-button post
- negative to a starter mounting-post (for ground)

Three 2-gauge or heavier ground straps
- clutch housing to frame on driver side
- clutch housing to frame on passenger side
- coil mounting screw to fender support-rod bolt on the firewall

All attachment points shiny until copper-impregnated conducting anti-oxidant goop is applied before installing attachment bolts.

Great info from everyone. Is there an advantage to sing the braided strap for the ground? If so, does it come in 2/0 guage? Now to find a source for 2/0 cable. I have a 31 Model A pickup. Were all 6v cable 2/0? If so, I have a good source?

Braided is not necessary.

On two of my trucks, I had a truck shop (or welding shop) make them both in 00 gauge - one red and one black (neither braided).

If you have them made, bring in your battery (to match posts diameters to clamps).

The original 6v cables were supposedly 2 gauge.

"2 gauge" is smaller, less current capacity, than "0" or "1/0" (same thing) which are both smaller than "00" or "2/0".

Used "4/0" on an old crawler tractor with 6V system, that was likely plenty of overkill... Cable size depends on expected load and bigger is better until it just cost more money than necessary to do the job really well.

2/0 seems to be sufficiently oversized for a Stovebolt. Use welding or good quality battery cable for positive and negative, use the heavy bronze or copper tin plated battery terminal clamps/ends professionally crimped or soldered. (Never use the lead clamp on "repair" battery cable ends) Use heavy copper ring/lug terminals on the other end, crimped or soldered. Heat shrink with the glue/sealer inside at each end.
Braided ground strap as original from belhousing to frame is just fine, no real advantage to an insulated cable instead. Good idea to also ground cab to the engine or frame as others have said.

Grigg

Someone told me that welding cable does not work very well and they are wrong. It makes an amazing cable. When soldering on the ends, I make sure that I solder the thousands of strands together, right at the very end, to start the process.

There are various opinions on welding cable vs. battery cable and also plenty of opinions on soldering vs. crimping.

None of the options in my opinion are actually "bad". Large cable of whichever type and however it is attached so long as it is secure is better than most of what you find for old cobbled together and wimpy/inappropriate battery cables.

- Yes - any bigger cable is always better than any 12v cable