The guy I bought it from told me that he sucked something up into the jet and it started making a loud noise. He got an estimate for the repair and decided to park it. I believe him on this. The trailer and boat registration both expired in '07 (the same year he bought it) When I got the boat home, I started it and verified that the jet makes noise. A friend and I partially took the jet apart and we found a baseball cap in it. We think that he continued to drive the boat with the baseball cap in there as opposed to shutting it down and getting a tow.
If it was just the cap in there, yeah, the whole boat would shake and shimmy like a mofo. Did it many times with rocks in the impeller. I really cant see the cap completely ruining the pump, though, unless he ran it a LOT ..........personally, I'd drop it in the lake and see what it does WITHOUT the baseball cap in it.......

These pumps have been running well for over 40 years sucking up you name it. I've personally seen diapers, ski ropes, sunglasses, and I think in was Ralph I heard processed a duck through one. The things are pretty damn resilient.
Brad and I kinda jacked up a rock grate and inducer on a wet bike that had problems on a beach once. Took a 3' prybar I carry in my boat to get the rock out, but the guy was happy as hell! Thing ran fine.
Anyways, welcome! 76Bonneville is you're go to guy on Rogers as you've figured out......I'm kinda curious how you managed to find and buy one without Ron beating you to it though.......
Ray