Probably correct. Have you tried physically blowing into the pumps?
Not sure how it turned out. He didn't say anything about having any issues doing it so I assume it's ok. He took it clear apart also...impeller out and everything.
/www.marinedepot.com/ps_ViewItem~idp...71~isKit~0.html
Here's some photos to show how dirty it really was.



Hope my power doesn't go out. Earlier there was a tornado warning about an hour south of us