Ground Strap Locations

[Jason Edge]

We often have discussions regarding the location of ground straps and the fact they can often cause electrical failure when not attached or not securely attached. Below is a run-down of the ground straps used. This post will be updated with additional pictures and info in the future and will be added to the Help Topics page.

Negative Battery Cable
These originally came with spring ring terminal type cables, but have often been replaced with bolt terminal cables over the years. Either type is fine, however, you need a clean tight metal to metal connection as with all ground connections!
Below is a picture of a original type spring ring terminal negative battery cable.

Below is a picture showing an original type spring ring negative cable with the short braided harness that attaches to radiator support:

Negative Battery Cable to Frame and Radiator Support
Battery cable negative to frame and short braided harness from bottom of battery cable to radiator support..where you have lots of electronics attached to or feeding through.  I often see newer bolt terminal cables installed on these cars with no ground back to the radiator support and wonder if that degrades the current flow.

Picture below shows the bottom of the negative cable connected to the frame; the short braided ground strap attached to radiator support. You can also see in this picture the right/passenger side forward lamp harness small ground wire attached to the frame all in that same picture.  That's 3 grounds in one area.

Right Frame Rail to Engine:
Very large heavy gauge ground strap from right frame rail just underneath the firewall cowl area, over to engine block at transmission. This is the main culprit for ground related starting problems. Here is a picture mounted on the frame which is just above the front transmission cross-member location:

63 Hydramatic Ground Strap at Starter Bold

Forward Lamp Harness to Frame
just in front of the radiator support on both left and right side (will cause headlights to not work. See picture above for example of Right side and the picture below of Left Side which is just beside the VIN # stamped on front frame rail:

 

Left and Right Cylinder Head to Firewall/Cowl Ground Straps
One ground strap from back of each cylinder head to firewall/cowl. 
See pictures below:

RIGHT SIDE CYLINDER HEAD TO FIREWALL:
LEFT SIDE CYLINDER HEAD TO FIREWALL:

Voltage Regulator Harness to Radiator Support
Small black ground wire mounts thru lower left base of voltage regulator bracket to radiator support.  Other end attaches to Alternator Ground Connector.

Alternator Ground
Grounds to radiator support at voltage regulator

Antenna Cable Ground
Attaches to firewall on lower right side near where cable comes through firewall. 

Dash Harness Ground
The dash harness ground wire attaches to the metal dash framing at the section of the dash near the center that attaches to the firewall.

Control Arm Ground Strap - Shaft to Control Arm - On Left and Right at Rear

Several Other Smaller Ground Straps
 There are many other grounds throughout the car such as the  AC compressor to water outlet pipe cover bolt, wiper motor to attaching bolt, power seat motor to seat rail, fuel sending unit to frame, etc. Also the relays such as horn, seat/window (on 64), etc generally complete the "control/feed" circuit by way of ground to the body somewhere.

[3ovpja9jmackq]

Awesome Jason!  Thanks for the info...

[Jason Edge]

Thanks, Todd. I just added 5 new pictures, 4 from the current parts car, showing additional ground strap locations.  The forward lamp harness and cylinder head to firewall show a lot of corrosion built up over 50+ years and one reason why these need to be inspected, cleaned, and reinstalled to make sure you have solid metal to metal contact. 

[25bwbuma9wtwr]

Can someone post the location on the engine where the right frame rail to engine attaches on the engine? I seem to not have that ground. Could be one of the issues with my starter

[Rob Barker]

Does anyone know where to buy the replacement straps for the "Control Arm Ground Strap - Shaft to Control Arm - On Left and Right at Rear" 

Lectric Limited and OPGI (who sells Lectric Limited) only sell replacements for the three major straps: engine to frame and both engine to firewall straps. 

Also accepting advance on gauge choice if homemade :)

Thank you in advance,

Rob

[Jason Edge]

I have them very good used for $10 each. Email me at [e-mail]