These engines have 2200 hours in a 84 Viking aft cabin. Original, never rebuilt. General consensus seems to be that the 671 pushed to 485HP is a ticking time bomb. If they were in a sport fisher I would think they were probably run hard. In a aft cabin MY, maybe not. Am I asking for trouble here? I'm hoping the broker will let me do a cold start. Other than a cold start, watch for smoke and how long it takes to clear, is there anything else I can do without getting a DD mechanic involved?