Research of Solutions and Cause Analysis on Opening Malfunction of Engine Pressure Limiting Valve
A pressure limiting valve opening malfunction occurs on a certain running engine,which lead to torque limiting and abnormal operating.This paper analyses the working principal of pressure limiting valve and electrical priming pump,the inner structure of fuel injection pump,the layout of low pressure fuel pipelines and the test results.It is determined that the positive pressure fuel generated by the operating of the electrical prim-ing pump is the cause of the pressure limiting valve opening malfunction.The experiment shows that the elec-tronic control unit can control electrical priming pump by adding relay,which can solve the openness malfunction of Pressure limiting valve effectively;In addition,through the analysis,changing the layout of low pressure fuel pipelines is also a good solving idea.The research on solutions above has an important guiding significance for the layout of low pressure pipelines and the matching of electrical priming pump.