"JacksPerson" wrote
Has this derailleur been unistalled and reinstalled since this issue arose?
If the base plate of the derailleur (held into place by a "C" clip around the mouting screw) that retains the spring that is inside the mounting base is not sprung and locked into place by the little bent over tab on the side of this plate against the nipple on the side of the derailleurs base then that adjustment will not do anything and it will appear like the spring could be broken.
I know that’s a bit confusing, but it’s hard to explain without being able to point it out.
Aha,
I haven’t reinstalled the derailleur but that would explain why the adjusting screw doesn’t seem to do anything. I will chack that out. Thanks JacksPerson