In case a diaphragm valve is opened, oil flows thru the multiple inlets(47a) of a filter(52) and a cooling path(51). The engine oil flowing in the cooling path(51) of the oil filter(52) is removed of the external material by a filter(46) and by a filtrating mesh(44). The cleaned oil is pushed to each lubricating point of the engine. In case the oil overflows in a housing(41), it pushes an overflow valve(63) to open, and is flowed to the lubrication line of the engine thru the upper center and an outlet(48a) of the overflow valve(63) and the filtrating mesh(44).
