I must have been in some real shallow water as I was about to put it on the trailer. I sucked up a rock about the size of a quarter. It made a hell of a racket. I shut it down and checked the inlet and there sat the rock between the grates. After more inspection I now need a new impeller and ware ring. How hard is it to do by myself? and do I need any special tools? Its a 2006 GTI/SE.