I have a pair of 3412’s 1989 d rated 760 hp in a 115’ yacht. The yacht was at the dock for about 30-40 days before running it. Last trip was SanDiego to Cabo 12 knot cruise whole time. Which is the usual running speed 10,000 hrs on engines. No rebuild. Clean exhaust Did an oil sample for sale and port engine had 24% fuel contamination with decreased viscosity. Cat mechanic said he just pulled the valve covers to check the “crossover” for a leak. Said everything looked good. Said it could be fuel pump or injectors or o ring rubber seals. Any idea what the possibilities are and how to get this ready to get back to Cabo? Mechanic said it is very tough getting parts for it. Any help is appreciated.
Get another mechanic in there. From your note; He did not do a thing for you. Sadly, your stuck. IMO, do not run the engine with out knowing where the fuel is coming from. A fuel washed lung will ruin a good engine. Change the oil, strap the propeller shaft (or pull the prop) and head back to where a real tech is, Or fly one in.