[El Campo]

Am building my 72 Chevy from the ground up and as I live in South Texas close to the coast rust is a giant issue. Therefore EVERYTHING on the truck is getting the best coatings possible. My question is how do you keep grounds on this without opening the truck to opportunitistic rust? Is tapping my holes after epoxy primer and paint and putting dielectric grease into them going to be the best method? Any other suggestions?

[T-bucket23]

Originally Posted by El Campo

Am building my 72 Chevy from the ground up and as I live in South Texas close to the coast rust is a giant issue. Therefore EVERYTHING on the truck is getting the best coatings possible. My question is how do you keep grounds on this without opening the truck to opportunitistic rust? Is tapping my holes after epoxy primer and paint and putting dielectric grease into them going to be the best method? Any other suggestions?

These are two good ideas. The other item to assure good metal to metal contact is star washers. They bite right into the metal.

[vicrod]

Before priming the metal, grind an area where the ground connection will be.
Next, solder a piece of copper sheet about 1" x 1" square to that area.
Mask the copper before paint.
Drill a hole through the copper and body/frame to make a tight connection when bolting on the ground lug.
Ground lugs should be tinned copper.
Paint or seal the connection area.

vicrod

[El Campo]

Excuse my ignorance but what is tinned copper? Is that when you solder and you coat the item with solder first? I like all the ideas set forth here. Especially if I use the star washers in conjuntion with the copper idea.

[vicrod]

Tinned is tin plating. Very common on electrical terminals and connectors.

vicrod

[EOD Guy]

I'd grind and prep the area, install your ground wire using star washers the seal the entire area, bolt washer etc with some undercoating spray or I like line-x bed liner..... that'll seal the entire area from corrosion and if needed, allow you to remove it later….. that’s how I did when I was stationed in Florida.

Copper will corrode in the salt spray and you will get some exposed copper when the star washers bite in when tightening the bolt. You could apply the sealant over the star washer/tinned copper etc…. but a lot of trouble when the 1st method works very well.

[nine4gmc]

Be sure you are grounded,
1. Body to Frame
2. Body to Engine
3. Body to Battery
4. Engine to Frame
5. Engine to Battery
6. Frame to Battery

I would grind any paint away and use star, or cutter washers on every connection, along with the dielectric grease to seal it up. The larger gauge wire, less likely to have issues with accessories later.

[Hotrod 80]

I have the same trouble hear . I use die electric grease on everything . I solder the connections ,, then grease them and heat shrink pre installed tubing squeezing out the excess grease . I do the smae thing on my boat trailer lights except i use black rtv to hepl seal the solder joint up . Im 4 miles from the bay .

[vicrod]

Star washers are a band-aid method for a good connection. Star washers may dig into the metal but will cause a decrease in the contact surface area required for good current flow.
Copper may oxidize when exposed to air but it remains conductive unlike rusty steel.
Contact compounds and conductive greases help to seal the connection.

vicrod

[EOD Guy]

Beg to differ with you, star washers make a very good ground connection, after they dig in, the inner portion of the washer comes in full contact with the base metal and makes a solid connection, probably why auto makers use them. rusted steel, like oxidized copper (copper sulfide) will not conduct electrical current worth a flip.

Both if protected from the elements will last a very long time with little maintenance, I believe grease will not last in hot areas (engine compartments) very long without reapplication etc.....

Using the copper takes a lot of time to prepare properly and if you have never tinned copper before..... good luck. Drilling a hole, adding a star washer, encapsulating the area with a good quality sealant is, IMO, the best method

[T-bucket23]

Originally Posted by EOD Guy

Beg to differ with you, star washers make a very good ground connection, after they dig in, the inner portion of the washer comes in full contact with the base metal and makes a solid connection, probably why auto makers use them. rusted steel, like oxidized copper (copper sulfide) will not conduct electrical current worth a flip.

Both if protected from the elements will last a very long time with little maintenance, I believe grease will not last in hot areas (engine compartments) very long without reapplication etc.....

Using the copper takes a lot of time to prepare properly and if you have never tinned copper before..... good luck. Drilling a hole, adding a star washer, encapsulating the area with a good quality sealant is, IMO, the best method

X2 star washers are the key, always have been

[sparkchaser]

Get one of these piloted bonding brushes from yardstore.com. they do a great job of removing paint, rust, or anything else that can keep you from getting a good ground. It does a lot nicer looking job than sandpaper or scraping with a knife. Star washers are used by the automotive industry, because they attach grounds directly to painted surfaces and star washers cut through the paint. The aviation and marine industries require grounding surfaces to be properly prepped and star washers are not used, because they damage the metal around the hole and wil cause cracks. There are many good sealers to apply over the connection. LPS3 does a great job and will last for years.

[stich626]

I just plug weld the grounding straps end ring then paint over the area..
no hole to allow rust to start, there is a reason they stoped drilling holes for trim.. rust..

[Danz28]

Ok, you guys all have good ideas. But what do you do like in my case? Ihave a 1987 Chevy Camaro Iroc Z-28 where you have to watch were you put the grounds because it is a unibody. Now what do you do?

[curtis73]

I like to use battery terminal converters... the kind that convert side post to top post.





Its just a lead nub with a bolt cast into it. What I do is make the grounds as one of the last things. Paint and coat what you want, then I drill and tap the frame for those bolts (I forget 5/16"?). Now the only exposed metal you have is in the threads.

You can put a little loctite on the threads if you wish - both to seal out water and to prevent the lug from backing out. It will probably reduce the surface area for current flow but not by much.

Then you can use one of those big flat braided straps to ground something. I have done that to ground diesel engine blocks to frames and never had an issue, even with the massive cranking amps they need.