I agree that if the helix is clean and lightly lubed, it should come right down when the engine lights off. The only other thing I could possibly think of is that the SOLENOID and/or key switch is staying engaged for a few seconds? I’d hook up a volt meter to the starter stud and operate the starter, to see if the stud continues to have positive voltage after the engine fires and you let go of the key.
Long live American manufacturing!
