Abstract:
Although direct measurements of the fuel injection pressure and the travel of the injector needle in conjunction with
measurements of the valve train mechanism timing can provide complete diagnostic information about the technical
conditions of the fuel injection and valve train systems, this requires the installation of sensors and other equipment
directly into the systems, which is possible within research laboratories but is generally forbidden during operation of
the ship. Malfunctions in the fuel injection and valve train systems can also be identified from the indicator diagrams
of an engine operating cycle, expressed as P(V) and P(deg) diagrams. The basic parameters of the engine operating
cycle, such as the maximum combustion pressure Pmax, compression pressure Pcompr, and indicated mean effective
pressure IMEP, can also be used to indicate deviations from proper engine operation. Using a combination of a vibration
sensor with an in-cylinder gas pressure sensor widens the capabilities of diagnostics for marine diesel engines under
operational conditions. A vibration sensor with a magnetic base can help in determining the timings of the lifting
and landing of the injector needle, fuel delivery by the fuel injection pump, opening and closing of the circulation of
heated heavy fuel oil, and opening and closing of the gas distribution valves. This also offers a promising solution for
diagnostics of the cylinder lubrication oil injectors
