2006 Johnson SD 30 HP 4 Stroke Outboards Service Manual, PN 5006592, Page 68Get this manual
MAINTENANCE SPARK PLUGS
SPARK PLUGS&CAUTION
Use thickness gauge to measure the spark plug gapThe correct gap is 0.031 to 0.035 in(0.8 to 0.9 mm)If the gap is out of specification, adjust it within the specified range
Only use resistor (R) type spark plugs with this engineUsing non-resistor spark plug will cause ignition system malfunctions Standard spark plug: NGK DCPR6E
Remove the spark plug
1Spark plug gap
1Spark plug
CAUTION