An all-purpose engine , comprising: an intake member which accommodates a filter part and has an opening , leading to a carburetor , in an end wall opposing the filter part ; an opening/closing member which is disposed between the filter part and the end wall , and opens/closes the opening ; and a working member which is disposed on an opposite side to the opening/closing member so as to interpose the end wall , and allows the opening/closing member to be operated, wherein the intake member has a cylindrical boss part which projects to an opposite side than the filter part to interpose the end wall , and constitutes a passage that returns a gas returned from a side of the carburetor to the carburetor via the opening , wherein the boss part is provided above the opening in the gravity direction of the intake member , wherein the working member includes: an arm part which extends along the end wall and is linked with the opening/closing member to interpose the end wall at one end part , and a holding part provided to another end part of the arm part , wherein the arm part has a bend section which is bent in a substantially semicircular arc shape and accommodates the boss part at an inner side, wherein the intake member , at a rear side, has a guide hole into which the arm part is inserted and guides movement of the arm part , and wherein the holding part is disposed to project from the guide hole to a side of a rear side wall arranged at the rear side of the intake member , among side walls surrounding a periphery of the end wall , is provided to be wider than the arm part , extends towards the opposite side to the carburetor along the rear side wall from the arm part and has a notch part at a surface opposing the rear side wall of the intake member , wherein the notch part is obliquely notched out so as to gradually become a narrow shape toward a linking part with the arm part . an intake member which accommodates a filter part and has an opening , leading to a carburetor , in an end wall opposing the filter part ; an opening/closing member which is disposed between the filter part and the end wall , and opens/closes the opening ; and a working member which is disposed on an opposite side to the opening/closing member so as to interpose the end wall , and allows the opening/closing member to be operated, wherein the intake member has a cylindrical boss part which projects to an opposite side than the filter part to interpose the end wall , and constitutes a passage that returns a gas returned from a side of the carburetor to the carburetor via the opening , wherein the boss part is provided above the opening in the gravity direction of the intake member , wherein the working member includes: an arm part which extends along the end wall and is linked with the opening/closing member to interpose the end wall at one end part , and a holding part provided to another end part of the arm part , wherein the arm part has a bend section which is bent in a substantially semicircular arc shape and accommodates the boss part at an inner side, wherein the intake member , at a rear side, has a guide hole into which the arm part is inserted and guides movement of the arm part , and wherein the holding part is disposed to project from the guide hole to a side of a rear side wall arranged at the rear side of the intake member , among side walls surrounding a periphery of the end wall , is provided to be wider than the arm part , extends towards the opposite side to the carburetor along the rear side wall from the arm part and has a notch part at a surface opposing the rear side wall of the intake member , wherein the notch part is obliquely notched out so as to gradually become a narrow shape toward a linking part with the arm part . <EOS>