My knowledge of perkins diesel is not vast, but I've rebuilt/replaced or worked on lots of them in Massey Furgeson tractors and combines. Would this engine you are referring to be the turbo 6-354. Six cylinder, 354 cubic inches. I'm not familiar with the engine in the previous post. The 6-354 is a great engine, as is the 4-236. Stone cold reliable, parts are cheap and available at most parts supply places. Depending on the marinization, most of those parts are easy to source. I'm not a big fan of turbos but they ok, as long as it has a watercooled turbine housing. The turbo'd 354 in most tractors will usually run about 6000 hours, in horrible conditions, loaded to the max, and spun at the top rpm. it should do better in a boat. I wouldn't be a bit concerned about it if it sounded good and held at least 15 pounds of oil pressure at idle, in gear, after a 30 minute run at full power, without getting hot. _________________________________________________________________ Get FREE Web site and company branded e-mail from Microsoft Office Live http://clk.atdmt.com/MRT/go/mcrssaub0050001411mrt/direct/01/