On my 1996 Z28 the batt neg grounding point is on the right side front motor mount. Having starting problems I consulted this website and was told such problems often involve the battery cables. I began my search by trying to remove the neg ground cable at the engine mount but the nut was stuck and when i put some muscle on it it the entire stud (to which the cable was attached) turned! This is a VERY confined area and I cant get any lock pliers on the stud. I can not understand why the stud could turn; it APPEARS to be screwed in to the mount but since the cable is still lockedon all that happens when I turn the nut us that the cable just twists all up. ONLY solution I think I have is ti cut the cable and the try to remove the stud. ANY OTHER IDEAS?

 

Did you use a decent rust penetrant?

 

OP

as Fred notes use penetrant on it, ideally it will come off then.

If you can't for whatever reason get it off or are not able to tighten the stud resulting in a now unstable ground... you could just cut the cable off and abandon that ground location. Buy a new cable long enough to go to an alternate block ground location more accessible to you

 

Wow; what a learning experience. Yes Fred, I used Kroil but--no luck. So, today, I tried heat and since the metal "bracket" (that was part of the grounding bolt) was wrapped around the bolt I put visegrips on the now twisted bracket and applied heat but still no luck. Finally I used Chimera's solution & simply cut the cable and UNSCREWED the bolt which, amazingly, revealed a recessed hole from which OIL came out! For sure I am no engineer but I can't conceive of a screw-in bolt being used that would (as mine did) loosen as you tried to take off the retaining nut! Why on earth would GM not require the bolt to be welded in place? Thanks both to

 

In my notes above I was continuing to thank both Fred (Injuneer) and Chimera96.

 

I don't have a F-body LT1 so don't know of the location you describe where the cable was grounded to. Fred is way more familiar with the F-body platform than I am

I don't know why or if the cable attachment point is to a bracket that is held with a bolt that goes into a oil passage. Of all the places to secure a ground available in any car....surprising that it is done that way.

In any event obviously put bolt back in block (maybe even with some RTV) to plug.

 

The wiring diagrams show the battery ground (G100, one of two) on the passenger side of the engine, between the A/C compressor and the motor mount. Given the location shown in Figure 69 (not very clearly shown) I could see that it might be into the water jacket. I don't know what oil passage would be present at that location. Are you sure it was oil, and not coolant?

 

It should be a blind hole and not going into any kind of passage. Perhaps it was some oil that had seeped down the block over time and migrated into there. Maybe it had been previously messed with and not tightened back properly. If it had oil or fluid of some type on it, I could see why it might not stay put while you removed the nut for the cable.

http://shbox.com/1/battery_cable_ground.jpg

 

Wonder if someone forced it in too deep and penetrated the blind hole???

You don't weld a stud. What would you do if you broke it off? I suspect the real problem was the nut was fused to the stud after 20 years. If you could have twisted the cable to get the stud to back out one or two threads, you could probably loosened the eyelet from the grip of the nut, and unscrewed the stud.