System and method for carburetor venting

An internal combustion engine assembly with a system for venting fuel vapors, the internal combustion engine assembly comprising:

• a fuel tank;
• a structure that receives incoming air for use by an engine of the internal combustion engine assembly;
• a connector assembly including a filter and a coupling device having first, second and third ports that are all connected with one another internally at a junction within the coupling device, wherein the first port is in communication with the fuel tank, the second port is in communication with the structure, and third port is in communication with an outside atmosphere indirectly by way of the filter;
• wherein at least one obstruction is formed within one or both of (a) a first channel within the coupling device linking the junction with the second port and (b) a second channel at least partly linking the second port with the structure, wherein the at least one obstruction partly but not entirely obstructs a flow path through one or both of the first and second channels.

A method of operating an internal combustion engine assembly, the method comprising:

• providing a coupling device having first, second, and third ports that are in communication with one another, wherein the first port is at least indirectly coupled to a fuel tank of the engine assembly, wherein the second port is at least indirectly coupled to a throttle structure of the engine assembly, and wherein the third port is in communication with an outside atmosphere by way of a filter;
• during a first time at which an engine of the engine assembly is not being operated, either (a) allowing a first portion of fuel vapors to proceed from the fuel tank to the outside environment via the coupling device and the filter, or (b) at least partly restricting the first portion of the fuel vapors from proceeding from the fuel tank to the outside environment due to the filter;
• and
• during a second time at which the engine is being operated, either (c) allowing a second portion of fuel vapors to proceed from the fuel tank to the throttle structure via the coupling device, or (d) allowing at least some air from the outside environment to proceed into the coupling device via the filter and toward the fuel tank, whereby a vacuum within the fuel tank is reduced.