Old engine model

GMW 73

The Gasparin GMW 73 is a special CO2 motor designed for the drive of sport aircraft models, including the regulations of the category FAI F1k. The motor has been designed for maximum utilization of energy originating from the compressed CO2 in a flight tank of 3ccm, or larger.



The construction of the motor has following characteristics:



•The crankshaft is positioned in two ball bearings

•The crankshaft pivot rotates in the ball bearing of the piston connecting rod

•The connecting rod is made of brass for better sliding properties of its ball pivot in the piston

•The sealing O-ring of the piston features a small cross section to prevent friction losses

• The stroke of the motor is extended to 6.5 mm for a better use of compressed gas energy

• The inlet tube conducting gas into the cylinder head has a larger diameter for the purpose of a better conversion of CO2 spray into gas before its processing in the motor

• By means of an insert positioned in the upper part of the cylinder it is possible to change the power output and the gas consumption of the motor

• By using the filling valve it is possible to discharge sharply the gas from the tank, thereby strongly under cool the tank for the purpose of the following highly efficient filling of the flight tank with liquid CO2 to a maximum level. This is 2.7 to 3.1 grams, when using the 3ccm tank.





Basic technical characteristics:

• Single Cylinder CO2 Motor

• Bore 3.8 mm, Stoke 6.5 mm

• Displacement is 73.72 cubic mm

• Weight, with pipes and 3 cubic cm tank, but without propeller, and its screw and washer, is .564 ounces.

• A very efficient black plastic propeller is supplied with this motor, 7" diameter. This propeller, including its screw and washer, weights .059 ounces.

• Total weight, with stock propeller, is .623 ounces, or 17.66 grammes.