I don't know if this is the correct place for this post but here goes. I recently pickup up a small (3hp) chipper leaf vac. The brand name is yardvark. I am trying to remove the impeller off the engine shaft. It appears to have a keyway, I have tried a puller but nothing also a lot of pb blaster. Any thought out there on this. Also would be nice to find info about this machine so far I'm not finding much. Thanks for any help