I have a 1988, 28 hp Johnson on a 16 Klamath aluminum boat. I slow troll for trout just above stall with a sea anchor, for the most part this works pretty good for catching fish. <br /><br />The fellow at the local marina tells me I am risking a high amount of carbon build up. I am asking you folks that know outboards, is this in fact the case?. This conversation was followed by a sales comment that maybe I should consider buying a "new" kicker motor.