Hi - My 1982 RENKEN runabout has a 2.5L OMC inboard engine with a OMC stringer outdrive. I hit a stump that was about 2 feet underwater. I bent the SKEG. I straightened it with two pieces of wood and a clamp. I ran the boat again and I still have a bad vibration at slow speeds. Any idea where this vibration is coming from and how to fix it?