Alan S N Ft Myers , FL February 27, 2015 Appliance: Whirlpool Undercounter Dishwasher WDF310PAAB1 Whirlpool Dishwasher Wdf310paab1 / : Top rack mot cleaning. How to replace Middle Spray Arm. Replaced center spray arm, found clogged with food from poor cleaning of the dishes when loading. So clogged I was unable to clear wash holes so was unable to turn. Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes