Diesel smell
Had the same problem with my 33, and found that stopping any very small leaks in fuel system by tightening nuts and clamps, or replacing washers, then scrubbing engine and bilge with appropriate engine and bilge cleaners made the smell disappear and not return. Most of the smell seeems to be spilled fuel on the engine surface or in the bilge under the engine that gets hot when the engine runs. this particuarly is a problem after bleeding the system or changing filters and spilling fuel.
