I have been writing “Common Pumping Mistakes” for Pumps & Systems for more than three years. Typically the hardest part of the job is topic selection so it will be fresh, educational and interesting. This month, I am writing on a collection of shorter subjects and baking them up into one article. Instead of a meal, we will have hors d’oeuvres. Hopefully it will satisfy your appetite. If you have been reading my column, many of these tidbits will be a review. These comments are based on single-stage overhung centrifugal pumps moving ambient temperature clear water, except when otherwise noted. Pumps are