| 摘要 |
PROBLEM TO BE SOLVED: To provide an engine capable of supplying negative pressure from a negative pressure part to a diaphragm chamber of a diaphragm type fuel pump and capable of preventing inflow of oil into a communication passage supplying the negative pressure.SOLUTION: A 4-stroke engine 1 includes a piston 9 and a carburetor 25. The carburetor 25 includes a diaphragm type fuel pump 109. The diaphragm type fuel pump 109 includes a pump chamber 1108 suctioning and discharging fuel, a diaphragm chamber 110 into which a pressure driving the pump chamber 1108 is supplied, and a communication passage 104 connecting a negative pressure part which is put into a negative pressure by displacement of the piston 9 and the diaphragm chamber 110. In the communication passage 104, there is provided a back flow check part (check valve 115) which allows only movement of fluid from the diaphragm chamber 110 toward the negative pressure part. |
