Abstract: A positioning structure for a clutch of an engine of a remote control model contains: a flywheel, multiple connection parts, multiple torsion springs, and multiple limitation elements. The flywheel includes a fitting element, a nut, and multiple fixing posts. Each of the multiple connection parts includes two opposites through orifices, an accommodation chamber, an abutting portion, and a recess. Each of the multiple torsion springs has a first central hole, a first contact segment, and a second contact segment. Each of the multiple limitation elements is rotatably fixed between each fixing post of the flywheel and the first central hole of each torsion spring, wherein each limitation element includes a support portion concentric with each fixing post, and the support portion has a second central hole rotatably fitted with each fixing post and has an external fence contacting with the first central hole.

Abstract: A crankshaft structure for a model engine contains a body and at least one fin member. The body is formed in an elongated shaft shape and includes a cam disc disposed on a distal end thereof and a connecting shaft extending outwardly from an end surface of the cam disc, a window defined on a middle section thereof, and a channel formed therein and passing through the end surface of the cam disc so as to inhale and exhaust mixed oil gas. The at least one fin member is mounted at a position of the channel where corresponds to the window.

Abstract: A crankshaft structure for a model engine contains a body and at least one fin member. The body is formed in an elongated shaft shape and includes a cam disc disposed on a distal end thereof and a connecting shaft extending outwardly from an end surface of the cam disc, a window defined on a middle section thereof, and a channel formed therein and passing through the end surface of the cam disc so as to inhale and exhaust mixed oil gas. The at least one fin member is mounted at a position of the channel where corresponds to the window.

Abstract: An electric rotary starter for an engine of a radio control model includes a motor mounted therein. A drive shaft is electrified and longitudinally connected to the motor and rotated by the motor. A conduct tube is electrified and movably sleeved on the drive shaft, wherein the conduct tube is insulated from the drive shaft. When starting the engine, the drive shaft is longitudinally inserted into the engine for providing torsion. Simultaneously, the conduct tube is longitudinally moved relative to the drive shaft to make the front end of the conduct tube contract with the engine. The conduct tube and the drive shaft from a circuit and the power from the electric rotary starter is transmitted to the spark plug in the engine to make the spark plug sparkle for starting engine.

Abstract: An improved remote control model engine assembly includes an engine body, a cylinder and a crane shaft chamber. A piston and a piston link rod are pivotally installed in the cylinder. The crane shaft chamber is horizontally and pivotally coupled to a crane shaft, whose end is connected to the bottom of the piston link rod for performing linking and rotating operations. A passage is concavely disposed at a middle section of the crane shaft corresponding to an air intake opening and penetrated axially through the crane shaft chamber. The passage is pivotally and axially coupled to a vane wheel by coaxial rotation, such that a high-speed operation of the crane shaft produces a powerful guide suction in the passage to suck a mixed petroleum gas into the crane shaft chamber and an internal upper space of the cylinder to enhance the igniting explosion effect and the horse power output.

Abstract: An electric rotary starter for an engine of a radio control model includes a motor mounted therein. A drive shaft is electrified and longitudinally connected to the motor and rotated by the motor. A conduct tube is electrified and movably sleeved on the drive shaft, wherein the conduct tube is insulated from the drive shaft. When starting the engine, the drive shaft is longitudinally inserted into the engine for providing torsion. Simultaneously, the conduct tube is longitudinally moved relative to the drive shaft to make the front end of the conduct tube contract with the engine. The conduct tube and the drive shaft from a circuit and the power from the electric rotary starter is transmitted to the spark plug in the engine to make the spark plug sparkle for starting engine.

Abstract: An engine for a radio control model includes an input axle partially extending out of the engine. A drive device is laterally mounted to the engine for driving the input axle when starting the engine. The driving device includes a first casing and a second casing abutting each other and respectively made of insulating material. At least one drive element is rotatably mounted in the driving device for driving the input axle. A polygonal hole is longitudinally defined in the at least one drive element and adapted to be connected to an extra power source. A conducting ring is sleeved on the at least one drive element and a wire is electrically connected to the conducting ring and a spark plug that is mounted in the engine such that the spark plug sparkles and the input axle provides torsion at the same time for starting the engine.

Abstract: A manual engine starter includes a starting device having a driven shaft selectively connected to a crank of the engine and a drive shaft connected to the driven shaft for driving the driven shaft and starting the engine. The drive shaft has a tubular drive portion formed with a guide side and the driven shaft having a driven portion that is rotatably received in the tubular drive portion and engaged to the guide side and moved along the guide so as to make the driven shaft moved along an axis thereof when the drive shaft is rotated to drive the driven shaft. A puller laterally is mounted the starting device for driving the drive shaft to drive the driven shaft.

Abstract: A wrench for an engine clutch of a radio control model includes a handle having a receiving space longitudinally defined in the handle. A control unit is rotatably mounted in the receiving space, and includes a first end formed with a press portion and a second end formed with a hook. The press portion presses a centrifugal lever of the engine clutch when mounting and the hook engages to the centrifugal lever when detaching. A drive unit is pivotally mounted to one end of the handle and corresponds to the press portion. The drive unit includes a hole defined in a free end thereof for receiving an input shaft of the engine clutch. A partition is securely laterally attached to the drive unit and has a separation extending therefrom. The separation is provided for easily detaching/mounting a torsion spring of the engine clutch.