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JeepHammer - Grounding Diagrams

28K views 31 replies 19 participants last post by  CJ7Guy1 
#1 ·
Hey Guys,

A while back I was reading a thread about Grounding Issues in Jeeps. JeepHammer had posted a few diagrams on what proper grounding should look like. I just cant seam to find the original thread. If anyone has seen this thread or has saved the documents can you please post them back up or send a link to the thread.

Thanks in advance

Josh
 
#6 ·
Grounds are something that are overlooked so much you simply wouldn't believe it!

This is absolutely true.
AMC (and most other vehicle manufacturers) wouldn't pay the extra $6 per vehicle to have dedicated grounds added to the wiring harnesses.

Chevy stated that it took an extra $6 per vehicle harness to add dedicated grounds for the military in 1983, and since all vehicle harnesses cost about the same amount...

As long as your vehicle lived through the warranty period (usually 12 months/12,000 miles to 36 months/36,000 miles)
Not having dedicated grounds wasn't an issue, and the company saved $6 per unit.

After the warranty period, any electrical problems were pretty well known to the dealership mechanics, so any electrical issues the owner had were money in the bank for the dealership.

If you got fed up after the warranty period, you would buy a new vehicle to get away from the problems...
This too was money in the bank for the dealerships.

Military vehicles required dedicated grounds for most accessories, even in fleet vehicles (non-combat rated vehicles that usually had much more extensive modifications) since they would be used long after the average warranty was expired...
--------------------------

If you pay attention to the diagrams I've posted, not only do I run a battery cable to the starter to ground it directly from the battery,
But I run a heavy wire to a grounding post on the fender, and run dedicated grounds from that...





Since the ignition produces between 20,000 volts and 45,000 volts, it needs a good ground, or your ignition coil will heat up and cook it's self...
A simple 12 Ga. dedicated wire to the head(s) will make sure your ignition spark energies have a good ground...
Run it off the grounding post on the fender.

That same ground can be run over to the ignition module and give the module a dedicated ground.
Costs you nothing but a connector and a little time, and gives your ignition module a new lease on life, and gives you faster, cleaner switching for the ignition coil, and that will result in more usable spark energy....

Since your alternator has a dedicated 12 volt, 10 gauge positive wire,
AND,
Since every electron your vehicle uses is produced by that same alternator,
WHY NOT GIVE IT A DEDICATED GROUND?
Only takes a short run of 10 Ga. wire from the grounding post to the alternator case, and no more alternator problems from bad grounds!

Your dedicated grounds should include, but not limited to,
1. The dash, so your gauges and wipers work since they are grounded there,

2. The tub, so your appliances work,

3. The grill shell, so your head lights/turn lights work,

4. Rear lights, tail, brake, turn, plate, backup, ect. should have a dedicated ground.

5. Fuel tank, so the sending unit works correctly.

6. The engine block, and in particular, the head(s) so the high voltage from the ignition has a clear path to ground,

7. The ignition module, so it doesn't have to fight for ground through the distributor housing.

8. The STARTER should have it's own dedicated ground cable that attaches directly to the starter housing!
This is the highest amp load your vehicle is going to have, so DON'T TORTURE THE CURRENT PATH!

9. The alternator. Since every electron your vehicle uses is produced in the alternator, you REALLY need a dedicated ground for it!

10. In my case, the electric radiator fan, electric fuel pump and a half dozen other things like air compressor,
 
#7 ·
Hammer, not to hijack the original post but I was hoping you would add in your thoughts on grounds so that everyone could read them again....thank you for doing so...this information is invaluable.
I have seen too many postings including my own regarding YJs with 'ghosts', just cutting out randomly, mine was solved with the addition of the distributor ground and now it runs pure. I for one have printed out your list of grounds and I am going to add them all in.
 
#8 ·
I am new to grounds and do not really understand what they are doing. I would like to add some or all of Jeep Hammers suggested grounds but I do not know what to connect to what to make the ground. Do I connect all of the items listed above to the negative terminal or the suggested brass bolt?

Confused here... I apologize, but Im knew to electronics as related to Jeep wiring.
 
#10 ·
I am new to grounds and do not really understand what they are doing. I would like to add some or all of Jeep Hammers suggested grounds but I do not know what to connect to what to make the ground. Do I connect all of the items listed above to the negative terminal or the suggested brass bolt?

Confused here... I apologize, but Im knew to electronics as related to Jeep wiring.
Any piece of steel connected to another piece of steel which indirectly is connected to the negative battery post is in effect a ground.

It's a path for electricity back to the negative side of the battery. The better the path, the fewer the problems you'll have, electrically speaking. If you have a relay with the ground wire connected to the drivers side fender, and the fender is connected well to the tub, and the tub has a wire going to the negative battery post, you have a path for electricity to follow. Now, if your drivers side fender has a 10ga wire connected to the negative post, it has a more direct and better path to follow with less resistance. Less resistance means better performance from the part.

You can't have too many paths back to negative, though there are points of diminishing returns. The only rule is that positive and negative can never touch, directly or indirectly.
 
#11 ·
I recently did this "upgrade" to my Jeep; also grounded the electric choke, alternator and distributor (still need to get the headlights and turn signals wired in). What a HUGE improvement! The Jeep idles better, runs smoother and stoped running on after I shut it off. I highly recommend this mod.

I'm working on dedicated grounds from the dash panel and all the "inside stuff".
 
#12 ·
Would love to see a picture or two of the grounding bolt/bus that you are all using for these dedicated grounds. I'm starting to work on this and want to ensure that my wiring stays clean. With such an abundance of grounds coming to one place, I'm just wondering what the end result looks like. Thanks......
 
#14 ·
Pick a spot under the battery tray and don't worry about what it looks like.

Worrying about how things look is for 'Barbie'.
Worrying about how they function is for Men, Off Roaders, people who hate walking to get a tow...

I actually use the bottom of the battery tray now, there is a stud that sticks down, and it works well for the grounding post...
 
#16 ·
I'm with Shawn, I wish I'd done a cleaner job, but what the heck, it works...

Like I said, there is a stud on the bottom of your battery tray, for the support arm, and it works fine for the ground stud if you want to hide it... Can't say it's fun to get at, but it's cleaner...
 
#17 ·
I added a dedicated ground cable a few months ago on my Jeep. I had a length of #8 cable and a bunch of #10, so all I had to buy was a few copper lugs. Here's an edited excerpt from my build thread:

The ground wire that was connected to the sending unit on my fuel tank was pretty corroded and barely connected to the bumper. I'm thinking this is why the sending unit was burned up when I bought the Jeep...



Since the gas tank is out of the Jeep now it seemed like a good time to install the dedicated ground wire from the front end to the rear. I'll want a good ground before I put the gas tank back in with the new sending unit anyway. I ran a #8 copper wire from the rear crossmember to the front passenger side motor mount, bolting each end down with a copper lug and plenty of never seize.



From the rear lug I also ran two #10 wires, one as a daisy chain for the tail lights (tied in to the body ground at each light) and one for the fuel tank sending unit. Since I have a 20 gallon poly tank this is the only possible ground connection the tank will have. At the front of the Jeep I passed the cable through the ground lug and up to the battery. There I crimped a large ring terminal that I could screw down on the battery post. Never seize went on all the connections. All ring terminals were crimped, soldered, and heat shrunk.


I also had the bright idea (we'll find out the next time I have to pull the tank how bright it was) to put some clips on the inside of the rear bumper to keep the wiring in place.



If you look at the wiring on the right side of the photo you can see where I bolted the copper lug to the crossmember.

2013/10/09


I also elected to replace the body ground strap to the battery. The old one was the flat braided style. It was very green and tattered. Since I have a marine starting battery I've got the screw terminals as well as the traditional posts. All of the grounds that I've added got screwed down on this screw top instead of the large terminal post. The body ground strap that I replaced was done after the other ground wires so it is a second ring terminal under the nut.

All of the exposed electrical connections got never seize on them to keep them covered.

Lastly, I made another ground cable up from the #10 wire to go from the body ground bolt through the firewall to the dash. The dash side is connected to one of the four mounting studs on the speedometer assembly. Sometimes when I work on the dash instruments I unbolt it from the body to get more access to stuff, and I'm likely to forget at first that the gauges need to be grounded if I turn power on. This way it will still be grounded and I won't accidentally burn anything up.

I don't have photos of everything, but I hope the above helps in some way (I did things a bit differently than Aaron or Shawn though, so I also hope I didn't add confusion instead of clarity).

Good luck,
Dave
 
#24 ·
Since the gas tank is out of the Jeep now it seemed like a good time to install the dedicated ground wire from the front end to the rear. I'll want a good ground before I put the gas tank back in with the new sending unit anyway. I ran a #8 copper wire from the rear crossmember to the front passenger side motor mount, bolting each end down with a copper lug and plenty of never seize.


All ring terminals were crimped, soldered, and heat shrunk.



I also had the bright idea (we'll find out the next time I have to pull the tank how bright it was) to put some clips on the inside of the rear bumper to keep the wiring in place.

Good luck,
Dave
Questions that might not be of interest to most:

- How are you doing the #10 (10 AWG) wire connectors: Where are you getting them, are you cutting off the insulation or find some that don't have it, what size rings are you using?

Also, where did you get that brass ground connector that looks like it is attached to the frame?

Thanks,
Patrick
 
#19 ·
Actually, if the ground goes bad on the gas tank, nothing will happen. The gauge will just not work.

If you loose the ground to the dash, then the regulator stops regulating and then you can burn up the gauge or the sending unit.

I was unaware that never seize had dielectric properties to it. What happens when it washes off?

I think the best way to keep a good ground is to use dielectric grease with a toothed washer with internal teeth.
As for exposed copper, there is just not any way to protect it. But I'll try the never seize and see if it works
 
#23 ·
Actually, if the ground goes bad on the gas tank, nothing will happen. The gauge will just not work.

If you loose the ground to the dash, then the regulator stops regulating and then you can burn up the gauge or the sending unit.
Thanks for the reminder John, no ground at the tank = no signal (but also no burning). Also, I did put a dedicated ground to the speedometer housing to help with the gauge grounding.
 
#20 ·
I use Nooxid grease on all my terminals. Since its conductive you can't just jam it in a connector. But, its great on ground and battery connections.

This picture is of one of my truck battery's. Its at least 3yrs old.

The grease also seems to resist engine bay washing. I've not had to go over any connections. I've been using it for at least 15years now. Ever since I volunteered to work a Saturday doing manhole inspections and redoing all the corona grounds. They always had a few feet of water and that ground bar was at the bottom.
 

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#21 ·
I don't believe never seize has dielectric properties. It does have aluminum and copper powder in it. I use it on battery and ground connections. It doesn't wash off easily, quite the opposite. If I had a bottle of no ox I'd probably switch to that. I do have a tube of dielectric grease that I use in connectors, spark plug boots, etc.
 
#22 ·
I use 'Never-Seize' to PROMOTE connections.
Grease keeps corrosion out, Copper promotes connection.
Can't use it on multipul wire connectors since it would short out between terminals, but it works good on 'Ground' and single pole (Starter Relay, Starter Terminal, ect.) Positive Connections.

If it's a multi path connector, then I use plain dielectric grease. No short out, and a pretty good level of protection.

When I use bare copper connections, I find that spray on battery terminal protector stays in place pretty good and adds some protection to the copper.

Bare Copper ANYTHING is just asking for problems. If you can see copper that is untreated, it's just waiting to suck up corrosion causing contaminants...
Grease it up, seal it up, treat it, but don't leave it bare.

I try to 'Tin' wire ends... I don't like 'Crimp' terminals since they leave that copper waiting to corrode with no protection.
Solder and tin the exposed wire, then use heat shrink if at all possible, and if not, dielectric grease or spray protection...
I just hate seeing bare copper ANYWHERE...
But I do live in the 'Rust Belt' and they do spend millions spreading salt, calcium chloride and who knows what all over the roads here...

Aircraft guys all whine "We don't solder connections"...
Can't remember the last time I saw an aircraft dragging it's wiring though slush that has so much salt in it it's making white foam...
 
#27 ·
#28 ·
Minnesota Mining and Manufacturing (3M) has always been my go to when I'm looking for quality that will last. I do the HF, HD, Lowes, etc brand if it's cheaper and I don't need it to last too long. Example is electrical tape. I bought a ten roll pack from HF for about five bucks on sale. Edges would unravel even under ideal conditions. I use the 3M stuff if I think I need it to last over five years. I'm sure there are other brands as good but don't scrimp with the cheap stuff if you want it to last.
 
#29 ·
I was re-reading one of my old JP Magazines yesterday and ran across a Randy's Electrical Corner regarding Rescue Tape, self vulcanizing and durable. My go-to remains 3M adhesive walled shrink tubing but this stuff looked promising, especially when dealing with failures in the field.
 
#30 ·
I remember that article. It was silicone tape. Very common nowadays but new to the market back then. It only sticks to itself. NAPA has their own branded version too. I have it in black, blue, red, and clear.
 
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