Been having a fairly low Voltage reading on my dash, of late, circa 11.7 volts. Yesterday I attempted to get to the bottom of it.
Went to remove the starter cover and the top mounting screw (which itself screws into the earth point) turned freely but with the stud coming with it. OMG, I say, no wonder things are a tad screwy. More importantly, why did it come loose? Was it because some numpty forgot to tighten it up last time?
Cleaned said stud, and single lug underneath it and re-assembled. Checked the main earth, which had previously been moved to one of the clutch housing bolts and all was good. Note to self, check this more often and not every 27 years!
Voltage on dash is now 12.5 volts, without the engine running. All good, comfort can be had from knowing things are right in the world. Still need to check my battery connections and will do so, in the next week.