1974 Johnson 135 HP Outboard Motors Service manual, Page 36Get this manual
1SENSOR MAGNET
Engine missing or sur ging may also be caused by insuffi cient, con taminated or excessive fuelAlter determining that this condition is not caused by carbu retionproceed (in order listed) to check the ignition systemSPARK PLUG The spark plugs should be rem oved and examinedIf the center electrode has worn to point, it should be replacedNaturally, any plug which has cracked insulator or shows other signs of damage should be replacedSee Figure 4- 8CHARGE COIL
CHECKLNG FOR SPARK
Use spark checking device, such as a
Figure 4-6Magneto C.DIgnition lywheelneedle type spark gap checker (see Figure 4-9) to chec for spark at the pl ug: leads Spal'k must jump 7 16" gap on needle type spark heckerIf sparking does not occur while ra'nking engine, proceed with fo llowing checksIf sparks are, apparent, proceed to "C HECKING TIMING"