Frame as ground? ...moving battery to rear...

[nvrstuk]

Moving battery to rear with 1/0 high quality welding cable and would like to use a weld on stud to use the frame as a ground. Frame is solid.

Pros or cons?

 

[DirtDonk]

Not sure, but it should work.
As long as you have good contact at the stud by the battery, then good contact at the stud near the starter, it should flow sufficient current.

Are you running lots of sensitive electronics? EFI setups or radios? Not sure if it makes a difference, but I'm wondering if there could be any kind of interference issue with the frame as the conductor, vs a shielded cable?
I think just making sure that everything is grounded well, especially the body, should help resolve this, but maybe someone else with more knowledge on the subject will know if there are any pitfalls.

Why don't you want to run a ground wire next to your positive though? Just cleaner? Less expensive? Something else or all of the above?

If you do go with the stud method, make sure you remember to run a full-size ground cable to the engine near the starter (or directly to a starter bolt) for the best performance, and tie the body into the ground scheme in multiple places.

Whatcha making by the way? Full buggy, or just relocating weight to the rear?

Paul

 

[Viperwolf1]

Should be fine. Make sure to use some dielectric grease on the frame connections so corrosion doesn't get in there. Go big on the block to frame cable too. If the battery is going inside it needs to be vented to the outside.

 

[nvrstuk]

Weight distribution and cleaner look. Been on the list for 10 years...finally doing it.

I run an AGM battery and no top, venting shouldn't be an issue.


Thanks for the corrosion tip under the stud surface.
Have thought of running the ground cable only for the winch. It's also 1/0.

Yes, sensitive electronics but with proper straps I should be OK.

 

[TAC71]

I have had my ground wire on a welded stud for 12 yrs with zero problems. Do use dielectric silicone to prevent rust though. Even the winch is on a welded stud.

 

[Broncobowsher]

Remember to add a ground cable from the frame to the engine as well. Factory setup the frame is insulated from the body and drivetrain with rubber engine mounts, rubber transmission mounts, rubber body mounts. The only factory grounded item on the frame is the sending unit for the main tank.

But the frame will work fine. Iron isn't the greatest conductor, but shear quantity of iron makes up for that. It will be fine.

My latest trick is finding a stainless bolt and welding that to the frame for the ground lug. I started doing that to my trailers as the trailer wiring always had grounding issues. I have had no corrosion issues with the stainless grounding lugs. Nothing fancy to attach them, use standard MIG welder with gas shield mild steel wire. Yes you can weld stainless to regular steel just fine. Some welding expert may step in and say what structural deficency that this will cause. But I am not doing this for structure, I am doing it for a solid eletrical connection. For that it works great. (ME does not understand IE needs)

 

[nvrstuk]

Good idea, thanks.

 

[Steve83]

I wouldn't use the frame as the main ground for the starter or winch - it's pushing the limit, and adding unnecessary resistance to critical circuits. I'd run a good ground wire from the batt to the starter bolt (or block), and also hit the frame/body somewhere along the way. That's the way Ford does it on '80-up trucks.

.

Another few feet for the winch is a good investment.

 

[DanWheeler]

nice project. I want to do the same eventually with 2 batteries mounted sideways in the cavernous space that was my fuel tank or maybe even in front of the rear crossmember embedded into the floor under the passenger seat.

where are you putting yours? What are you using for cable ends?

 

[jim3326]

I cut out the floor below the passenger seat, welded up a box and am venting it to the outside. As long as they don't make the optimas bigger there is enough room for 2 side by side.

Jim W.

 

[nvrstuk]

What's nice about the new AGM batteries is you can lay them on their sides or mount 'em upside down...doesn't matter. Common for sprint boats to mount them on their sides...

Fit them in some tight spots like that...