not enuf pressure not cleaning

I think that my dish washer is not putting out enuf pressure. Water sprays out of the spinners, but they don’t spin. I am looking for a manual for teardown and trouble shooting. Since it drains fine impellers are probably ok. But I am not shure about any seals. Looking threw the parts manual here the seal has been updated. Now how to get to it? Any help is greatly appreciated.
thanx

Dustin

Model # is MDB7100AWB sorry. I have removed the spray arm and filter and cleaned filter and screen. But no change.