Hi... I have a kioti/kubota lk3054 4wd tractor. I just replaced the engine with a used one. When I release the clutch pedal I have a noticeable vibration, not real bad but enough to feel it in the seat. It gets worse as rpms increase and does it in neutral and in gear. I assumed something was wrong with the pilot bearing so I split it back into. The bearing is intact, it spins but has one spot with a slight bit of drag, doesn't seem like enough to cause the vibration. The clutch looks fine and I didn't have the vibration before the engine swap. I am going to put a new pilot bearing in but wanted some input on what else I could check for before I put it back together. Thanks in advance