First Pass Yield Improvement by Eliminating Base Plug Leakage in Feed Pump Manufacturing

Base plug leakage caused by the inefficient tightening of the base plug in the feed pump of a diesel engine is the common problem in the field. The leakage of fuel is mainly due to the inefficient sealing of copper washer which is used to seal base plug and feed pump housing. A case study has been done in the industry to reduce the rejection of feed pump due to leakage of fuel through base plug in diesel engine. In this paper an effort is made to identify the factors which cause the leakage of fuel by using why-why analysis. It is found that some significant factors are the main cause in the feed pump assembly causing the major problem. Hence a trial on the present design is made and suggested the improved design by providing an undercut in copper washer landing area of the base plug.