The invention concerns a method for controlling the fuel supply to an internal combustion engine at start-up. The fuel supply system can be set in at least two start modes, a lean mode and a rich mode, and the selection of mode is based on an evaluation of a previous start attempt or successful run. The invention also concerns a carburetor (10) having a fuel supply system including a main fuel path (13) with an actively controlled fuel valve (26) and an idling fuel path (14) branching off from the main fuel path (13) downstream of the valve (26). The fuel supply system further includes a start fuel line (23, 423) starting upstream (FIG. 1) or downstream (FIG. 4) of the fuel valve (26) and ending in at least one start fuel outlet near and downstream of a choke valve.

An integrated ignition and electronic auto-choke module for an internal combustion engine and an internal combustion engine including the same. In one aspect, the module includes a housing that is configured to be mounted to an engine block of an internal combustion engine. The housing may contain at least a portion of a first temperature sensor that measures a first temperature indicative of an engine temperature. The housing may also contain a controller and at least a portion of an ignition circuit. The controller may be coupled to the first temperature sensor and configured to determine a starting position of a choke valve based on the first temperature and operate an actuator to move the choke valve into the starting position accordingly.

An integrated ignition and electronic auto-choke module for an internal combustion engine and an internal combustion engine including the same. In one aspect, the module includes a housing that is configured to be mounted to an engine block of an internal combustion engine. The housing may contain at least a portion of a first temperature sensor that measures a first temperature indicative of an engine temperature. The housing may also contain a controller and at least a portion of an ignition circuit. The controller may be coupled to the first temperature sensor and configured to determine a starting position of a choke valve based on the first temperature and operate an actuator to move the choke valve into the starting position accordingly.

The invention relates to a method for adapting the composition of a mixture of fuel and combustion air. The mixture is supplied to a combustion chamber of a mixture-lubricated combustion engine in a work apparatus. The fuel is supplied to the combustion engine via a controlled fuel valve. In an operating state (I) of the combustion engine, the quantity of fuel is metered by the fuel valve. For the purpose of adapting the composition of the mixture, the combustion engine is shifted into a special operating state (II) which differs from the normal operating state (I). After starting, the combustion engine is operated in a first rotational speed range (B) for a prespecified operating time (T.sub.min), wherein, after the prespecified operating time (T.sub.min) has elapsed, the operating state (II) for adapting the composition of the mixture is initiated by a prespecified user action.

The invention relates to a method for adapting the composition of a mixture of fuel and combustion air. The mixture is supplied to a combustion chamber of a mixture-lubricated combustion engine in a work apparatus. The fuel is supplied to the combustion engine via a controlled fuel valve. In an operating state (I) of the combustion engine, the quantity of fuel is metered by the fuel valve. For the purpose of adapting the composition of the mixture, the combustion engine is shifted into a special operating state (II) which differs from the normal operating state (I). After starting, the combustion engine is operated in a first rotational speed range (B) for a prespecified operating time (T.sub.min), wherein, after the prespecified operating time (T.sub.min) has elapsed, the operating state (II) for adapting the composition of the mixture is initiated by a prespecified user action.

In at least one implementation, a method of operating a combustion engine, includes determining a temperature equal or related to a temperature of an engine at an engine start and comparing the determined temperature to a temperature threshold, determining if an engine operating condition exceeds an engine threshold within a threshold time after the engine was started, and if the determined temperature is below the threshold temperature and the engine operating condition remains above the engine threshold and the threshold time has not passed, providing an enriched fuel and air mixture to the engine.

An integrated ignition and electronic auto-choke module for an internal combustion engine and an internal combustion engine including the same. In one aspect, the module includes a housing that is configured to be mounted to an engine block of an internal combustion engine. The housing may contain at least a portion of a first temperature sensor that measures a first temperature indicative of an engine temperature. The housing may also contain a controller and at least a portion of an ignition circuit. The controller may be coupled to the first temperature sensor and configured to determine a starting position of a choke valve based on the first temperature and operate an actuator to move the choke valve into the starting position accordingly.

An integrated ignition and electronic auto-choke module for an internal combustion engine and an internal combustion engine including the same. In one aspect, the module includes a housing that is configured to be mounted to an engine block of an internal combustion engine. The housing may contain at least a portion of a first temperature sensor that measures a first temperature indicative of an engine temperature. The housing may also contain a controller and at least a portion of an ignition circuit. The controller may be coupled to the first temperature sensor and configured to determine a starting position of a choke valve based on the first temperature and operate an actuator to move the choke valve into the starting position accordingly.

A choke system for an internal combustion engine includes a carburetor having a choke valve disposed in a passage; a cooling fan providing a variable air flow; an air vane moveable in response to the variable air flow; an air vane linkage coupling the air vane to the choke valve, the air vane linkage operating the choke valve by the movement of the air vane; a manually operated choke control; an override linkage coupling the choke control to the choke valve; and a thermally responsive member configured to engage the override linkage to retain the choke in a partially open position above a threshold temperature. The choke control may be moved to a first position in which the choke control overrides the thermally responsive member and the air vane linkage to maintain the choke valve in a closed position.

A choke system for an internal combustion engine includes a carburetor having a choke valve disposed in a passage; a cooling fan providing a variable air flow; an air vane moveable in response to the variable air flow; an air vane linkage coupling the air vane to the choke valve, the air vane linkage operating the choke valve by the movement of the air vane; a manually operated choke control; an override linkage coupling the choke control to the choke valve; and a thermally responsive member configured to engage the override linkage to retain the choke in a partially open position above a threshold temperature. The choke control may be moved to a first position in which the choke control overrides the thermally responsive member and the air vane linkage to maintain the choke valve in a closed position.