There are lots of 4 and 5 cylinder Mercedes deisels used in sailboats. I recently saw a 46-foot Hinckley (top-o-the-line) with one. If they are marinized correctly, they are truly great. If my old Perkins ever gives out in my sailboat, I'm going Mercedes.

__________________
1984 300Sd 210k

Former cars:
1984 300D 445k (!!) (Strider) Original (and not rebuilt) engine and transmission. Currently running on V80 ( 80% vegetable oil, 20% petroleum products). Actually not, taking a WVO break.
1993 300d 2.5 275k. Current 120/day commuter
1981 300SD 188k (Hans) Killed by a deer