Why operating a propulsion diesel engine at less than 30% of designed normal load for prolonged periods should be avoided?
Such operation will result in carbon formation on the combustion chamber surfaces. When an engine runs at low loads, the turbocharger efficiency drops. Consequently, less quantity of air is supplied to the cylinder. The quantity of fuel which is burnt get reduced. At the same time, the fuel will not burn efficiently. Unburnt fuel will lead to carbon formation and the combustion chamber surfaces will get coated with the carbon deposits.
