FUEL FILTER ABNORMALITY DETECTION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a fuel filter abnormality detection device capable of detecting abnormality in a fuel filter.SOLUTION: A fuel supply device 3 has a main filter 6 to filtrate fuel. An auxiliary filter 12 is installed at a downstream side of the main filter 6. A filter capacity of the auxiliary filter 12 is smaller than the same of the main filter 6. The auxiliary filter 12 collects foreign matters at the downstream side of the main filter 6 and generates a fuel pressure change indicating abnormality in the main filter 6. A bypass passage 14 connecting an upstream side of the auxiliary filter 12 and the downstream side thereof has an opening/closing valve 15 and a bypass filter 16. The auxiliary filter 12 generates a predetermined fuel pressure change due to clogging thereof in the case that: the main filter 6 is not installed; an element is not installed in the main filter 6; the main filter 6 is an inferior product having low filter performance; or the element in the main filter 6 is damaged. Thus, abnormality in the main filter 6 can be detected through the auxiliary filter 12.