Way worse than that, Karl. If you install a TOP checkvalve in any
well deeper than 32ft, you're going to get a whale of a waterhammer
....

You and jano raise valid points. But that pump is 24 years old, it will have
to be replaced when I pull it this time. Big $, about $4K I'd guess. I only
get paid in the fall, so I'm going to try and limp by for a few months.

Karl