1980 Johnson 2HP Service Manual, Page 16Get this manual
TROUBLE
POSSffiLE CAUSE
1MOTOR WILL NOT ST ART
FUEL SYSTEMSee Section No fuel Fuel shut-off valve not opened Fuel vent screw not Speed control not advanced (thrott1e closed) Engine flooded Old fuel Clogged fuel filter Choke not c10sing comp1ete1y Fuel system fau1ty IGNITION SYSTEMSee Section Spark p1ug lead not connected Spark p1ug fou1 ed or linkage improperly adjusted Invert ed breaker Sheared flywhe e1 key Ignition syste fau1tySee Section Carburetor and magneto not synchronized Air 1eak at manifo1d gasketswarped manifold (backfires) Broken leaf va1ves (backfires) Excessive carbon pistons and cylinder head Stuck piston rings, or scored cylinder, or pistonSee Section Poor fue1 mixtoo much 1ubricant Carburetor adjustment(too leanbackfires) (too richexcessive fuel) Choke not operating properly Air 1eaks at packing nuts or core plugs In1et need1e and seat worn or sticky gasket damaged Incorrect carburetor float setting Altitude or temperature ho rsepower 10ss FUEL ANKSee Section Fau1ty fuel line Fuel tank or filter p1ugged Fue1 line restricted Fue1 vent screw not Fue1 shut-off valve restricted DEXHAUST GAS ENTERING CARBURETORSee Section Exhaust cover screws leaking Cover plate gasket damaged Exhaust elief obstructed Lower bearing housing gasket eaking Cracked exhaust housing Lower bearing housing screwsSee Section Exhaust cover gasket 1eaking Power head gasket improperly installed or damaged Head gasket leaking (warped cylinder head) (water in cylinder) Water intakes obstructed cover ir bleed restricted Water passages or tube obstructed impeller damaged impeller plate worn impeller worn Water tube improperly installed Impeller cover grommet leaking