How is the wire feed cable assy held in place at the wire feed assy on the lincoln weld pack 100?

You do need to make sure the shank portion of the assembly goes through and almost touches the feed wheel. Then snug the set screw or thumbscrew down until it locks that shank into place.

I will see if I can upload a picture of how my Century is held in place. Yours will differ a bit, but will be largely similar in concept although the clamping method will differ.

If your entire drive assembly is loose, that needs to be secured to the inner bulkhead. You do need to make sure the shank portion of the assembly goes through and almost touches the feed wheel. Then snug the set screw or thumbscrew down until it locks that shank into place. I will see if I can upload a picture of how my Century is held in place. Yours will differ a bit, but will be largely similar in concept although the clamping method will differ. If your entire drive assembly is loose, that needs to be secured to the inner bulkhead.

I am not finding a window to upload image, but it dawned on me- if you have a groove on the end of the welding cable shank that is visible when installeld, it would be retained by a clip. My Century uses 2 bolts to press a block against that shank to lock it in place for example. It is also possible your set screw fell out, or if new- was not drilled at the factory. If it needs to be drilled, a 10-32 or 1/4-20 set screw should be perfectly adequate. I am not finding a window to upload image, but it dawned on me- if you have a groove on the end of the welding cable shank that is visible when installeld, it would be retained by a clip. My Century uses 2 bolts to press a block against that shank to lock it in place for example. It is also possible your set screw fell out, or if new- was not drilled at the factory. If it needs to be drilled, a 10-32 or 1/4-20 set screw should be perfectly adequate.