I've noticed recently I've got a vibration when cruising. Dove on running gear found lots of barnacles on shafts & prop nuts, with much less on props, struts & rudders. I was able to clean the shafts, rudders, struts & props, but not my nuts (smile). While cruising today at 1700 rpm's, I checked the shafts in the engine room. I found a slight oscillation of the port shaft log. Can I continue to run the boat till haul out, or does this need immediate attention. Vibration is worse at higher speeds and when making turns.