Painkiller
Member
Last weekend there were 5+ footers on Lake Michigan. I hit a wave and my boat came out of the water and came down hard. I have twin 8.1 L Horizons with ZF inboard v drives. After that hit I got a reoccurring (every 45 90 seconds) growling noise and vibration at 2000 RPM and above especially when riding the big waves. While limping back in I isolated the noise and vibration to the starboard side. In addition, I put up the engine hatch and put my hand on the engines and could not feel anything but normal vibration and could not hear the growling noise while in engine compartment. Later that day I ran the boat in no wake zones (700 RPM) for a couple of hours with no noise or vibration. Any thoughts on what this could be?
