1979 Johnson 2HP Outboards Service Manual, Page 9Get this manual
Model Number 2R79 Horsepower (B.I.Acertified) (1.4 kW) at 4500 rpm Full throttle operating range to 4800 rpm Test tank with test wheel 3900 rpm Test wheel Part Number 316021 Idle rpm 650 rpm Engine type Single cylinder, stroke cycle Bore and stroke 1-916" bore 1-3 8" stroke (39.69 34.93 Piston displacement 2.64 cubic inches (43 Piston ring sets (2 per set) Standard Part Number 383920 0.030" (0.76 oversize Part Numbel' 384312 Width of ring 0.06250.0615 in(1.5881.562 Piston assemblystandard Part Number 384651 0.030" (0.76 oversize piston less rings Part Number 384666 Crankshaft size journa 0.75020.7497 in(19.05519.042 Bottom journal 0.75020.7497 in(19.05519.042 Connecting rod crank pin 0.67000.6695 in(17 .01817.005 Carburetion Single barrel f10at feed, with high and low speed adjustments Float level setting Flush with casting 0.620" (15.7 Inlet needle seat 0.050-0.053 (1.271.35 Use #55 drill as gage Cooling system Centrifugal Propeller gear ratio 12:25 Propeller drive pin Part Number 316558 Propeller 7-114 4-12 Speed control Single lever, synchronized throttle and spark Weight 24 lbs(10.9 kg) Fuel capacity Gravity feed integral tank qt(0.95 litre) Starter self rewinding Ignition Flywheel magneto Spark plug Champion J6J14 Spark plug gap 0.030 inch (0.8 Spark plug torque 17-11220-112 foot-pounds (24-27 N'm) Breaker point gap 0.020 inch (0.5 Condenser Part Number 580321 Capacity 0.18 to 0.22 MfdCoil Part Number 580971