[Shimaze]

Attention: All B-Body owners, the wire going from the negative battery terminal to the body is a likely cause of any electrical problem you may have. And if you don’t have any problems now, I still strongly suggest you still fix the problem before it happens. The wire going from the negative battery terminal to the body attaches to the body with a stupid sheet metal screw and a star washer. The only real surface to conduct electricity comes from the screw cutting into the hole. This may be OK for the first ten years, but after it gets a little dirty (i.e. slight corrosion or rust), the ability of this connection to conduct electricity is severely compromised. The end result is the negative ground problems that these cars have (in my opinion).

My fix was to use a bolt thru one of the existing holes already near the battery. I sanded off the paint to get down the bare metal. I used a fender washer to make sure I had a good contact between the bolt & the body. I then used one of the side post bolts that have a stud on the end of it and ran two 10 awg wires from the battery terminal bolt to my special grounding bolt. Now all the circuits in the car have a good solid connection to negative side of the electrical system! This connection feeds everything except for what is attached to the engine (i.e. starter & alternator).

I have for several months been having a bad issue with the car not wanting to start. It would turn over very slow and half the time it would just click. These are classic signs of a low battery or a starter that pulls too much current. I checked all three: the battery, starter, & alternator. They all tested fine. I was at my wits end. I had swapped in three different batteries from my other cars and even removed the starter and had it checked at two separate shops. Every test passed and the car still started extremely slow …when it started!

I got to looking around at the battery (for the 20th time) and saw what appeared to be two wires from the negative terminal to the body ground. Upon closer inspection, I found that the insulation burned off of the wire and made it look like it had two wires. Burned copper wire will conduct electricity, but not too good. I bet this problem has caused my fuel pump wires to burn and the turn signal switch to fail and is most likely the reason why I have never had all the brake lights working!

Just wanted to share the information with others that may not know this, but I suspect the guys that have been around for awhile have known this problem for years. So I don’t mean to come off like I discovered a new planet… Good luck, Shimaze

 

[Coney]

Thanks for the info, I looked at the ground you are talking about for a long time and thought how ****ty of a connection that was, now I will fix it

 

[ssondubs]

My fix was to use a bolt thru one of the existing holes already near the battery. I sanded off the paint to get down the bare metal. I used a fender washer to make sure I had a good contact between the bolt & the body. I then used one of the side post bolts that have a stud on the end of it and ran two 10 awg wires from the battery terminal bolt to my special grounding bolt. Now all the circuits in the car have a good solid connection to negative side of the electrical system! This connection feeds everything except for what is attached to the engine (i.e. starter & alternator). , Shimaze

Sounds like a great idea. Do you have any pictures?

 

[k gee]

Pics would be good.
My screw hole stripped out and I had to use a bolt/washer/nut (I think it is on this current Caprice I have lol).

But yea, the lil screw and star washer is a JOKE!

I do have the upgraded 1/0 battery cables though...but if you are stock, I'd upgrade to the BIG 3 even if you don't run a big stereo.

 

[ssondubs]

Pics would be good.
My screw hole stripped out and I had to use a bolt/washer/nut (I think it is on this current Caprice I have lol).

But yea, the lil screw and star washer is a JOKE!

I do have the upgraded 1/0 battery cables though...but if you are stock, I'd upgrade to the BIG 3 even if you don't run a big stereo.

Hahaha...me to I stripped that fender sided ground hole doing the big 3 upgrade too. I would like to see what the pro's on the forum do so I can have a idea.

 

[Mikeceli]

Re-Opening this thread to add INFO.

While you near the battery..........follow the Black wire fomr the right headlight bulb socket. A few inches away from the socket, in the harness, 4 black ground wires are crimped together. Mine were corroded. I cut them apart and soldered them together, making a good ground.

 

[grandpas wagon]

Thanks for this good post...........again. On a similar note - check the 3 ground wires at the coil. They use flimsy connectors which are prone to break off. I bundled all three together in a heavy duty ring terminal and then crimped and shrink wrapped it. Now very strong and won't break.

I once got into a heated discussion about wiring with a punk "know it all" He insisted ground wires weren't important like the positive ones "because they don't carry electricity". I kept telling him that the circuit has to be complete or it is no good.......... it didn't have much affect on him.

 

[WindSSurfer]

Speaking of ground wires

Re-opening this thread to discuss the block to firewall ground wire. I have a wire braid from the block to the firewall that I replaced several years ago with one from another vehicle. What if any difference would it make if I used a heavier insulated wire like 10 or 8 gauge?

 

[1slow96]

Negative lead from battery to ground of body

I like 4ga.ground straps. Also ground body to frame,and motor/trans to frame. Electrical problems stay away from my door.

 

[WindSSurfer]

I like 4ga.ground straps. Also ground body to frame,and motor/trans to frame. Electrical problems stay away from my door.

4 ga. ground straps like this one?

Taylor 20314 4 Ga. Grounding Strap 14in

 

[1slow96]

Yep,but I also added some heavier gauge ground cables which were made from left-over lengths from 0/2ga. welding cable I constructed the battery cables from.(delcity.net)

 

[Nor-CalSS]

Had a no start issue on Saturday. Tried another battery and had the same issue then I remembered this thread. I re did my ground wire to where it was actually touching metal with a larger area rather than just the screw part . Fired up with no issues. Thanks for this post.


Since this turned into a "ground location" thread lets get it stickied.

 

[swampfoxjr]

could this b the reson my lights flicker while running...

 

[CapriceLt1]

pics?

 

[4DoorSS]

Re-opening this thread to discuss the block to firewall ground wire. I have a wire braid from the block to the firewall that I replaced several years ago with one from another vehicle. What if any difference would it make if I used a heavier insulated wire like 10 or 8 gauge?

Just installed some of Gary's battery cables. I too hate the fender connection and will be figuring out something better/more rigid for the fender connection. Maybe a nutsert on the fender that I can use a threaded bolt in? Somthing similat that Gary uses on the bracket for his headlight harness.

On the "heavier insulator wire" that Windssurfer was asking about, I would stay away from doing that. I THINK the reason they use a braided wire there is for flex-ability. The engine can move quite a bit under load. With a heavy rigid wire there like you suggested, the connection to the firewall may work loose as the engine moves. That's my guess on this and I would just stay with the flex-able ground wire there.

EDIT - Something like this to replace the Starwasher and Screw in the fender. Just drill a larger hole in the fender and use a nutsert and Stainless bolt.

http://www.avdel-global.com/en/products/threaded-inserts/thin-sheet-nutsertr.html

 

[CapriceLt1]

The engine to firewall ground fell off as i went to grab it lol. The bolt on the back of the head is NOT coming off. Anywhere else i can ground it to so that i have an engine to firewall ground? I know aluminum isn't a good one so the intake is off and i was going to go from a head bolt to the firewall but the eye hole would have to be huge and i don't have those so where would be a good one?

 

[1slow96]

There are other locations,but you may need a longer strap. I continue to recommend the 4ga. braided. On the rear of the engine on the drivers side is a bolt holding a clip that secures the harness going to the transmission. There are also unused threaded holes on the trans itself. I grounded everything to the frame,and then grounded the engine to the body. Rock solid voltage is the result,and no more mysterious electrical problems.

 

[CapriceLt1]

After being out there all day I am going to take a break. Its hotter than the devils draws outside lol. I will try those later tonight when its cooler. I have 4 ga. cable, not braided but i think i can make it work.

 

[4DoorSS]

Went to Harbor Freight yesterday and picked up this kit for $17 and also got a FREE gift for Memorial day....

http://www.harborfreight.com/45-piece-threaded-insert-riveter-kit-1210.html

The Nut-serts with the HF piece are Aluminum which will conduct current flow fine and will not rust.

Here is the old setup with the Star Washer and the little sheet metal screw....Not a Good Connection especially with the heavy gauge of Gary's cables. Notice Gary's 2 Relay Headlight Kit/Bracket tucked nicely in the fender and out of the way?

I then got a drill bit that was just slightly smaller than the 1/4" Nut-sert I intended to use. I also went with a bolt that is a little longer and used a flatwasher against the insert, then the cable, then another flat washer, then a lock washer and the the bolt.

Drilled the hole in the same location which is also boxed behind the hole so it would be difficult to get a nut behind this location. Made sure the nutsert fit tight into the opening, then sanded the area around the hole where the Nut-sert would be installed. I also used some dieletric grease around the nutsert so when I crimped it into place I would have a tight connection with good electrical contact. Before doing this, I used a DVM to measure continuity from the bare metal on the fender and had .02 ohms....EXCELLENT! Here is the Nut-sert installed in the fender.

Here is the cable installed with a bolt and assorted washers, along with a good coating of dieletric grease on all pieces. The connection is very rigid now and connectivity is excellent with one less thing to worry about.

I will add aditional ground straps as 1slow has mentioned. I will pick up some braided flat cables and ground the tranny to the frame and the body to the frame somewhere. I look forward to brighter lights and no more flickers.

EDIT - This worked so well and I have quite a few Nut-serts left that I may just do the same thing with the Ground Strap on the Firewall. This connection is also how the Fender connection used to be. Why GM used these crappy connections, I'll never know. Maybe due to cost. But there sure seem to be a lot of electrical Gremlin's that can usually be tracked down to a bad Ground wire somewhere.

EDIT2 - Nevermind on the Firewall connection. It appears there is a threaded stud that comes off the firewall for this connection.

 

[CapriceLt1]

Awesome! can't wait for more. I need these gremlins gone!!!