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eric8 09-21-2022 11:48 AM

Engine ground strap
 
I have a 77 C10 that I’m pretty sure is virgin and unmolested. I noticed in the factory wiring diagram it shows what is supposed to be an “11 gage ground strap engine to body ground” connected somewhere toward the rear of the drivers side of the engine. Does anyone have a photo of how this is connected from the factory? Mine clearly has nothing back there resembling a ground strap. Everything on the truck works normal.

MJN 09-21-2022 02:03 PM

Re: Engine ground strap
 
Typically there is a ground strap from the rear valve cover bolt to the cab firewall, I've also seen them attached to the rear of the LH cylinder head. I don't have a picture handy right now to share. Usually they get forgotten when pulling the engine and get torn off too.

eric8 09-21-2022 02:17 PM

Re: Engine ground strap
 
From what I’ve found on here, the previous Gen trucks (67-72’s) had holes drilled on each side of the middle of the firewall (where the transmission tunnel area starts to form) and ground straps coming from both valve covers. Can’t find any pics of a 73-87 setup.

Something else I’ve found by researching this, is that Chevelles not equipped with a factory radio apparently didn’t come with the engine to firewall ground straps? Apparently they were to prevent radio interference? This is a factory radio delete truck so maybe there’s some truth to this? I’d still like to add them since the truck now has a radio. If anyone has a pic I’d appreciate it.

MJN 09-21-2022 02:38 PM

Re: Engine ground strap
 
1 Attachment(s)
Heres the factory engine to cab ground strap on my '74 K20. Firewall to rear bottom valve cover stud.

eric8 09-21-2022 02:43 PM

Re: Engine ground strap
 
Quote:

Originally Posted by MJN (Post 9126443)
Heres the factory engine to cab ground strap on my '74 K20. Firewall to rear bottom valve cover stud.

Thanks!

Dead Parrot 09-21-2022 09:41 PM

Re: Engine ground strap
 
Quote:

Originally Posted by eric8 (Post 9126438)
...

Something else I’ve found by researching this, is that Chevelles not equipped with a factory radio apparently didn’t come with the engine to firewall ground straps? Apparently they were to prevent radio interference? This is a factory radio delete truck so maybe there’s some truth to this? I’d still like to add them since the truck now has a radio. If anyone has a pic I’d appreciate it.

The strap from the firewall to the valve cover is fairly common. My 68 Impala, 75 C10 and 79 Camaro all had one very similar to MJN's photo. They all came with factory radio.

More grounds are almost always a good thing. Many weird electrical issues are due to poor or missing grounds.

GOPAPA 09-23-2022 09:34 AM

Re: Engine ground strap
 
A pack Rat climbed up in and around the motor of my 71 and our dog chewed the ground strap nearly off all the while barking at the rat,, when I opened the hood the Rat ran for its life,, When I started the truck it almost did not start because of the ground strap being almost chewed off ,,I found the chewed ground strap and changed it and all was good again ,

77 ChevySport 09-23-2022 09:53 AM

Re: Engine ground strap
 
1 Attachment(s)
eric8>Here is a picture of my stone stock 77 Sport(LS9) engine.Note>
Ground Strap from firewall to cylinder head on passenger side. There
is no ground strap like this on the drivers side. Larry:chevy:

Getter-Done 09-23-2022 10:26 AM

Re: Engine ground strap
 
1 Attachment(s)
Here is Another ground that is often deleted.
That Is the ground strap on the negative battery cable
that goes to the radiator core support.

At the time the owner is just trying to get it back running.
Or that's the only cable available without the ground strap.
Or it doesn't matter to the owner that it is not there.

Attachment 2220475

eric8 09-23-2022 12:15 PM

Re: Engine ground strap
 
Quote:

Originally Posted by Getter-Done (Post 9127119)
Here is Another ground that is often deleted.
That Is the ground strap on the negative battery cable
that goes to the radiator core support.

At the time the owner is just trying to get it back running.
Or that's the only cable available without the ground strap.
Or it doesn't matter to the owner that it is not there.

Attachment 2220475

Yep I just finished replacing the negative cable on mine. With a genuine AC Delco one like you have pictured. What made no sense to me is that the small wire with the butt splice is actually a fusible link on the replacement. I’ve never heard of a fusible link on the negative side of a system? Definitely wasn’t one there on the factory one.

Axle 09-24-2022 02:49 PM

Re: Engine ground strap
 
On my 73 Nova, 83C10, and 81 C1500, the ground is firewall to a bell housing bolt.

wazzabie 09-25-2022 05:11 PM

Re: Engine ground strap
 
Quote:

Originally Posted by 77 ChevySport (Post 9127110)
eric8>Here is a picture of my stone stock 77 Sport(LS9) engine.Note>
Ground Strap from firewall to cylinder head on passenger side. There
is no ground strap like this on the drivers side. Larry:chevy:

Is this a low mile engine? Would the alternator and starter be original to the engine?

eric8 09-25-2022 05:35 PM

Re: Engine ground strap
 
Quote:

Originally Posted by 77 ChevySport (Post 9127110)
eric8>Here is a picture of my stone stock 77 Sport(LS9) engine.Note>
Ground Strap from firewall to cylinder head on passenger side. There
is no ground strap like this on the drivers side. Larry:chevy:

Wow that is pristine. Thanks for the photo. Great reference.


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