MANUFACTURED BY: |  | JONSEREDS FABRIKERS AB |
 | | PARTILLE, SWEDEN |
SERIES OR ASSEMBLY NUMBER: | | XN 621 |
SERIAL NUMBER PREFIX: | | |
YEAR INTRODUCED: | | 1970 |
YEAR DISCONTINUED: | | 1982 |
ENGINE DISPLACEMENT: | | 56ccm (3.4 cu. in.) |
NUMBER OF CYLINDERS: | | 1 |
CYLINDER BORE: | | 45mm (1.77 in.) |
PISTON STROKE: | | 35mm (1.378 in.) |
PISTON RING THICKNESS: | | |
CYLINDER TYPE: | | Aluminum with Nikasil coated bore |
INTAKE METHOD: | | Piston ported |
MANUFACTURER ADVERTISED H.P.: | | 2.65kW @ 7700 rpm |
WEIGHT: | | 6.3 kg (14 lbs.) powerhead only |
OPERATOR CONFIGURATION: | | One Man operation |
HANDLEBAR SYSTEM: | | Anti-vibration |
CHAIN BRAKE: | | none |
CLUTCH: | | Centrifugal |
DRIVE TYPE: | | Direct |
CONSTRUCTION: | | Die cast MAGNESIUM |
MAGNETO TYPE: | | Pagani |
CARBURETOR: | | Tillotson HS-21D series |
MAJOR REPAIR KIT: | | RK-23HS |
MINOR REPAIR KIT: | | DG5-HS/T |
AIR FILTER SYSTEM: | | Nylon mesh cylinder |
STARTER TYPE: | | Jonsereds automatic rewind |
OIL PUMP: | | Automatic, worm gear driven |
MAXIMUM ENGINE RPM: | | 10,300 |
IDLE RPM: | | 2,900 |
IGNITION TIMING: | | 2.7mm before TDC |
BREAKER POINT SETTING: | | 0.3 to 0.4mm |
FLYWHEEL/COIL AIR GAP: | | 0.30 mm (0.012 in.) |
SPARK PLUG TYPE: | | Champion CJ7Y |
SPARK PLUG GAP: | | 0.5 to 0.6mm (0.020 to 0.024 in.) |
CRANKSHAFT MAIN BEARINGS: | | Ball |
FUEL TANK CAPACITY: | | 1 litre |
FUEL OIL RATIO: | | 25:1 |
RECOMMENDED FUEL OCTANE: | | Regular |
MIX OIL SPECIFICATION: | | Two-cycle chain saw mix oil |
CHAIN PITCH: | | 3/8 in. |
CHAIN TYPE: | | Chisel |
BAR MOUNT PATTERN: | | 18 link |
SHORTEST GUIDE BAR SUPPLIED: | | 33cm (13 in.) |
LONGEST GUIDE BAR SUPPLIED: | | 58cm (23 in.) |
COLOUR SCHEME: | | Red and Silver enamel |
PAINT CODES: | | |
ILLUSTRATED PARTS LIST: | |  |
SERVICE MANUAL: | | |