In the ship MV Vishva Kaushal, where Sulzer RD engine was fitted, there used to be frequent scavenge fires. Each time, the engine used to be stopped and the scavenge spaces used to be cleaned and engine restarted. Though the fire was getting stopped for a few days, but on the long voyages it was giving a big nuisance and restlessness to watch keepers. During one such occasion, it was decided to do thorough investigation. On investigation it was found that the line leading to the scavenge drain tank had a filter and this filter was choked with cotton rags. On clearing this, it was found that the scavenge fire had completely stopped and it was not giving frequent problems.