1971 Johnson 4HP Outboard Motors Service Manual, Page 7Get this manual
SPECIFICATIONS Model 4W71 (weedless gearcase) 4R71 (standard gearcase) hp at 4500 gear ratio drive 17:28 4W71 Model 12:25 4R71 Model Part Number 203230 1 8" 13 16" stainless steel 4R71 Models Standard8" diameter 5-12" pitch, blade Optional8" 4-12"blade 4W71 Models 6-3 8" diameter 5-12" pitch, blades Speed control Weight Engine type and stroke Piston displacement Piston ring sets (2 standard .030" oversize Diameter of ring Width of ring Lbscompression recommended when pressed Piston less rings standard .030" oversize Crankshaft size top journal center journal bottom journal Connecting rod crank pin Carburetion cylinder, cycle alternate firing 1-9 16" 5.28 1-3 8" stroke inches Single lever, synchronized throttle and spark 4W71 Model35 lbs4R71 Model35 lbs
Horsepower (B.I.Acertified) Full throttle oprange Test tank with test wheel
4000 to 5000
4200 Part Number 316021 for 4W71 Part Number 316960 for 4R71
Lift vacuum fuel system Fuel capacity Starter Ignition Spark plug
3 galtank and plug in hose gallons Swing-Arm, self-rewinding Flywheel magneto Champion J6J,14mm .030 inch 17-120-12 foot-pounds .020 inch Part Number 580321 .18 to .22 Mfd