Check all of your O-Rings and make sure they're still in tact. Then take the spray tips out and make sure there is no debris in them. If there is something in one of the spray tips it won't let the bar spin or it will make it vibrate violently. If there is something lodged in one of the spray tips DO NOT stick anything in there bc you will mess the spray pattern up eventually. Just tap the threaded side on a flat surface and let the debris break free on their own. Make sure you flush out the swivel and the bar really well before putting the spray tips back in. When you thinks it's been flushed enough, do it again, lol. I also run a filter just before the swivel and that seems to help a lot. If none of that works, your pressure may be set to high for that surface cleaner.