MANUFACTURED BY: |  | SKIL CORPORATION |
 |  | CHICAGO, ILLINOIS, U.S.A. |
SERIES OR ASSEMBLY NUMBER: |  | 1644, 1645 |
SERIAL NUMBER PREFIX: |  | |
YEAR INTRODUCED: |  | 1969 |
YEAR DISCONTINUED: |  | |
ENGINE DISPLACEMENT: |  | 4.2 cu. in. (69ccm) |
NUMBER OF CYLINDERS: |  | 1 |
CYLINDER BORE: |  | 2.0625 in. (52.3 mm) |
PISTON STROKE: |  | 1.250 in. (31.7 mm) |
PISTON RING THICKNESS: |  | |
CYLINDER TYPE: |  | Aluminum with cast iron sleeve |
INTAKE METHOD: |  | Piston ported |
MANUFACTURER ADVERTISED H.P.: |  | |
WEIGHT: |  | 13.75 lbs. (6.23 kg) powerhead only |
OPERATOR CONFIGURATION: |  | One Man operation |
HANDLEBAR SYSTEM: |  | Rigid |
CHAIN BRAKE: |  | none |
CLUTCH: |  | Centrfiugal, 3 metal shoes |
DRIVE TYPE: |  | Direct |
CONSTRUCTION: |  | Sand cast magnesium housings |
MAGNETO TYPE: |  | Flywheel magneto |
CARBURETOR: |  | Tillotson HS series |
MAJOR REPAIR KIT: |  | RK-23HS |
MINOR REPAIR KIT: |  | DG-5HS/T |
AIR FILTER SYSTEM: |  | Flocked wire screen |
STARTER TYPE: |  | Fairbanks Morse automatic rewind |
OIL PUMP: |  | Automatic with manual override |
MAXIMUM ENGINE RPM: |  | |
IDLE RPM: |  | |
IGNITION TIMING: |  | Fixed |
BREAKER POINT SETTING: |  | 0.015 in. |
FLYWHEEL/COIL AIR GAP: |  | Position is fixed |
SPARK PLUG TYPE: |  | Champion J6J, Autolite A3X, AC M44C |
SPARK PLUG GAP: |  | 0.025 in. |
CRANKSHAFT MAIN BEARINGS: |  | Ball |
FUEL TANK CAPACITY: |  | 1.85 Imp. Pints |
FUEL OIL RATIO: |  | 16:1 |
RECOMMENDED FUEL OCTANE: |  | Regular grade 72 to 83 |
MIX OIL SPECIFICATION: |  | Two-cycle chain saw mix oil |
CHAIN PITCH: |  | 3/8 in. |
CHAIN TYPE: |  | Oregon 73D |
BAR MOUNT PATTERN: |  |  |
SHORTEST GUIDE BAR SUPPLIED: |  | 15 in. (38 cm) |
LONGEST GUIDE BAR SUPPLIED: |  | 24 in. (60 cm) |
COLOUR SCHEME: |  | |
PAINT CODES: |  | |
ILLUSTRATED PARTS LIST: |  | PM1644IPL1.pdf |
SERVICE MANUAL: |  |  |