Mortimer Schnerd wrote:
....
went out this morning and cleaned off some crud from the battery
terminals, then checked the snugness of the connections between battery
and starter. Just doing that seemed to correct my problem as the three
times I attempted to start the engine: it engaged vigorously each time.
A very different experience from a couple of days ago.
....

What did I suggest in very first response????

Remove each cable at each end and clean both cable ends and mounting
locations thoroughly. At battery ends particularly one of the foaming
battery cleaners/neutralizers would be good followed by the thorough
rinse they recommend and then a terminal protectant.

Also make sure to trace the negative battery cable to the ground mount
location and do your duty there as well.

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