A well functioning and maintained fuel treatment system is vital for the safe operation of the diesel engine. Provided that the fuel is within the limits specified by ISO and CIMAC, then there is a good probability that the oil injected into the engine will have a harmless level of contaminants.
There are however a number of pitfalls to look out for, which, one by one, or in combination with each other might reduce the efficiency of your cleaning system.
A good cleaning system correctly installed and operated, with a built in high level of performance is the best way to protect the diesel engine and also to provide a safety margin for off spec fuels or random conditions outside the control of the operator.
 MER, May 2000.
 J. Vardi and C.W. Siegmund, Products Research Division, Exxon Research and Engineering Company. Removal of Cat Fines From Marine Residual Fuel Oils Eastern USA Branch. The Institute of Marine Engineers. New York. October 3 1985
 A Pallmar, Sludge: in the tank or in the engine, Motor Ship, June, 1999.
 D. Coghill, The effect on centrifuge performance of the addition of used lubricating oil in residual fuel. Result of a joint study between BP Marine and Alfa Laval. The 20th International Bunker Conference, Oslo, Norway, October 1999.