The trimmer finally died… I suppose it was at least partially my fault as I did very little to care for it properly though on the other hand I’m not sure it ever functioned well. In any case, when I retrieved the trimmer from the shed and tried to crank it after several attempts I determined that it finally had given up. Gas was leaking out of the engine case.
I detached the trimmer attachment from the motor and tossed the motor. Perhaps some future yard sale shopper will benefit from the purchase of an inexpensive trimmer head along with a tiller and edger.