Grounds - Useful Information

[demian5]

Please add to this thread for ground connections but in my experience with GM vehicle, the grounds should be:

• Cable between battery and engine (alternator bracket, water pump bolt, or bolt on front of block by fuel pump)
• Cable between battery and vehicle body (inner fender usually)
• Cable between engine and vehicle body (firewall and valve cover bolt usually)
• Cable between engine and chassis (valve cover bolt and frame)
• Cable between chassis and vehicle body (under cab)

I had to add one between my cluster and firewall because of the usual cluster lighting issues many have.

A simple check to see if you have a ground problem (slow crank when hot for example):

Take a set of battery cables (which you were going to ask for a jump start for the slow crank issue anyways) and do this:

• Hook one end to the engine block, the other end to the frame.
• For the other jumper cable, connect one end to the body and the other to the frame or engine block.
• If it cranks OK, verify you have good, clean, and sufficient grounds.

[LockDoc]

-
Here is an older thread, It spans quite a few years (2010-2018) but it covers just about everything.

https://67-72chevytrucks.com/vboard/...d.php?t=422234

Really shouldn't have to add a ground to the cluster if the original one is there and it is making good contact. Most of the time a bad ground to the cluster is because the cab isn't grounded correctly.

LockDoc

[custom10nut]

Subbed.

[Steeveedee]

We're working on some really old iron. Any connection made at the factory is suspect, even if someone did a frame-off, because corrosion waits for no one. (Rust never sleeps" :P ) My temp gauge went south, probably from corrosion. I'm thinking about replacing the whole instrument panel with custom gauges, to eliminate that printed circuit board which is certain to be corroded, based on what else I've seen in the cab. This on a truck that lives in the "irrigated desert" in southern California.

[Andy4639]

I have added extra grounds to all my old vehicles. Just good preventive maintenance to do it as said with older vehicles.

[OregonNed]

I remade all my grounds when the box was off a while back. Probably overkill but I have access to great bonding materials where I work.

[randy500]

Originally Posted by LockDoc

-
Here is an older thread, It spans quite a few years (2010-2018) but it covers just about everything.

https://67-72chevytrucks.com/vboard/...d.php?t=422234

Really shouldn't have to add a ground to the cluster if the original one is there and it is making good contact. Most of the time a bad ground to the cluster is because the cab isn't grounded correctly.

LockDoc

AGREED on the cluster ground, dumbest thing I have ever heard of....the cluster ground is via a clip to the dash, if there is a ground problem its in the ground straps at the engine, the inner front fender or the cab, FIX the actual Problem...............

[Shaky]

Originally Posted by OregonNed

I remade all my grounds when the box was off a while back. Probably overkill but I have access to great bonding materials where I work.

Any idea what that stuff is called? I'd like to track some down to have on-hand.

[OregonNed]

Originally Posted by Shaky

Any idea what that stuff is called? I'd like to track some down to have on-hand.

I took a quick look around and it doesn't appear to be manufactured any more. I could probably get some to you if you wanted to pay the shipping cost.

[Burbor]

Looks like that braid is made by 3M: http://m.3m.com/wps/portal/3M/en_US/...294469250&rt=d

[Shaky]

Originally Posted by OregonNed

I took a quick look around and it doesn't appear to be manufactured any more. I could probably get some to you if you wanted to pay the shipping cost.

Wow - that's a generous offer. It looks like Burbor tracked it down - I'll probably order that since I'll probably be going through a significant amount between my projects and some other people's...

Thanks!

[Shaky]

It looks like McMaster has it here:

https://www.mcmaster.com/#bonding-an...pment/=1bmek1r

[Richard2112]

I recently added a ground strap from my cluster to the firewall and inside the engine compartment, from the firewall to the block. Going to add yet another but haven't decided exactly what location yet. As had been said, grounds can't be trusted on vehicles this old and they are generally neglected. Sufficient grounding improves a great many things and increases the life of components.

[mike16]

I have a ground going from the underside corner of the rear bumper to the sheet metal across from it.

[OregonNed]

Glad you guys found something still being made out there! I still use the smaller brade from the back of both heads to the firewall. The big braid is great for chassis grounds.