McCulloch Model 73 American Production

Model: 73  -------------------------------------------------------------------------------- MANUFACTURED BY:  McCULLOCH MOTORS CORP.   LOS ANGELES, CALIFORNIA, U.S.A. SERIES OR ASSEMBLY NUMBER:   YEAR INTRODUCED:  June 1955 YEAR DISCONTINUED:  September 1956 ENGINE DISPLACEMENT:  7.3 cu. in. (120cc) NUMBER OF CYLINDERS:  1 CYLINDER BORE:  2.50 in. (63.5mm) PISTON STROKE:  1.50 in. (38mm) CYLINDER TYPE:  Aluminum with cast iron sleeve INTAKE METHOD:  Rotary valve MANUFACTURER ADVERTISED H.P.:   WEIGHT :   OPERATOR CONFIGURATION:  One Man operation HANDLEBAR SYSTEM:   CHAIN BRAKE:   CLUTCH:  Centrifugal DRIVE TYPE:  Gear reduction CONSTRUCTION:  Die cast magnesium MAGNETO TYPE:  McCulloch CARBURETOR:  McCulloch diaphragm type MAJOR REPAIR KIT:   MINOR REPAIR KIT:   AIR FILTER SYSTEM:  Wire screen element STARTER TYPE:  McCulloch automatic rewind OIL PUMP:  Manual OPERATING RPM:   IGNITION TIMING:  fixed BREAKER POINT SETTING:  0.018 in. FLYWHEEL/COIL AIR GAP:   SPARK PLUG TYPE:  Champion J8J SPARK PLUG GAP:  0.020 in. CRANKSHAFT MAIN BEARINGS:  Ball and roller type FUEL TANK CAPACITY:   FUEL OIL RATIO:  1/2 pint to 1 gallon (20:1)1 RECOMMENDED FUEL OCTANE:  Regular MIX OIL SPECIFICATION:  McCulloch two-cycle mix CHAIN PITCH:  1/2 in. CHAIN TYPE:  McCulloch BAR MOUNT PATTERN:   SHORTEST GUIDE BAR SUPPLIED:  18 in. (45 cm) LONGEST GUIDE BAR SUPPLIED:  36 in. (91 cm) COLOUR SCHEME:  McCulloch Yellow enamel