Well because of work and other pressing obligations I put off changing the starter, but when I got stranded at Home Depot today I wasted no time after getting a jump to pass by O'Reilly's on the way home and pick up a rebuilt, while I left the engine running and sure enough, the starter was the problem. The guy from AAA told me the battery was fully charged and it barely cranked enough to start with his battery pack hooked up. I knew all the connections were clean, so by this time there was little doubt, actually, none.
Well, anyway after wrestling the old one out and installing the rebuilt I put all the tools away, cleaned the grime off my hands and went out to savor the joy of a fast cranking, quick starting engine. Bingo! it started right up! Only problem was the starter kept cranking. I turned the engine off but the starter kept cranking! SH#T!!! I popped the hood and tried to yank off a battery cable, but I had cinched them both down tight. I ran inside to get the 1/2 inch wrench to loose the bolt on the cable. By this time it's dark and I didn't bring out the flashlight, so I'm fumbling around doing this by feel. Finally got it loose and pulled the cable off the post and the starter stopped spinning. whew!
So I put the cable back on the post, not knowing what to expect, but nothing happened. I leave the hood up and the cable loose on the post and go to try again, being ready to sprint back to the battery to pull the cable if necessary, but this time the starter motor disengaged. I tried it several more times with no drama. The engine started and the starter disengaged every time. Cool, but not cool. I disconnect the battery cable so as not to have to worry about the starter spontaneously starting.
I go to Google and look up 'starter motor keeps cranking' and found this not to be an entirely uncommon problem. The possible cause that appealed to me the most was that a new or rebuilt starter has tolerances that are tight, causing the solenoid not to disengage. This problem, I was lead to believe, can work itself out as the starter does its work . I thought maybe the minute and half that this one was cranking while I fumbled to pull the battery cable might have done just that. I'm hoping that's the case because that would mean no more work. But it seems just as likely from the symptoms that the starter relay was stuck. But this has never happened before, so I'm leaning toward the rebuilt starter as the source of the problem. But tomorrow I will pull the relay and pop it open to inspect the contacts for any sign of weld spots.
I'm assuming that the starter was cranking the engine after I turned the key off and not just spinning. The fact that it continued for so long cranking at a good solid rpm tells me I should have no starting problems for quite a while. But I am going to disconnect the battery at night until I feel comfortable that it won't spontaneously start :-)
I also see that this thread seemed to take on a life of its own after my last post. I have some catch-up reading to do!
Jack