630.16303401 Kenmore Elite (by Bosch) dishwasher upper arm spinning lower not!

[mbed]

Greetings all!

Puzzled by water flow path...upper arm is spinning fine, lower arm dead in the water (pun intended). Have hard water, cleared out a stalagtite like mess a few months ago...do sulfamic acid occasionally...parts diagrams don't show a diverter valve. Any other obvious or non-obvious suggestions as to where to find problem? Thanks in advance!

mbed

[16345Ed]

Part number: 00437051

I would make sure this is clear, holes not plugged up. Run water through it at sink to test it. 

[mbed]

Domo Sensei Ed!

It was clear prior to posting...swap out a pair of the center filters.  What I did was remove the lower rack, the lower arm, the Dishwasher filter
Part #: 170841 & Dishwasher fine filter Part #: 441905 (Substitution: 00441905).  poked a bit down the center hole where the lower arm inserts and ran it a bit with everything wide open...water began to come out of the port then so no idea of what actually fixed it.

Thanks again!