No water pressure from lower wash arm

Never having repaired a dishwasher before, I disassembled everything I dared to until I found the root of the problem--part of the impeller had broken into several little bits. It wasn't apparent where the pieces came from, but the on-line diagrams and product photos helped. The broken impeller didn't want to come off the shaft, so I just crunched it up with a pair of vise grips. That seemed to be the gentlest solution for the pump bearings. The bits of impeller also took out the pump housing, which I could have ordered with the impeller had I been more observant. [insert four more days of washing by hand here] Inspect all parts for damage and clean out all stray chunks of food and plastic before reassembling!