Spark plugs are electrical devices for firing the explosive mixture within an internal combustion engine. And to keep the outboard motor in good working condition, we’ve listed spark plug maintenance, spark plug type and gapping requirements outlined by the manufacturer.
Model application: 2001 thru 2008 Suzuki DF90T
Spark plug type
Only use resistor (R) type spark plugs. Using a non-resistor spark plug can cause malfunctions in the fuel injection and ignition system.
Standard spark plug: 2001 thru 2003 NGK BKR6E, 2004 thru 2008 NGK BKR6ES
Inspect spark plugs every 100 hours or every 6 months, whichever comes first. Replace spark plugs every 200 hours or every 12 months, whichever comes first.
When checking used spark plugs, inspect for carbon deposit on its base. If carbon is present, carefully remove it with a pointed tool or with a spark plug cleaning machine.
Replace the spark plug if damage is present i.e. broken insulator, pre-ignition, damaged thread or if other mechanical damage is present. If the spark plug appears burnt or excessively worn, replace spark plug.
Spark plug gap
Using a thickness gauge, measure the spark plug gap. If the gap is out of specification, adjust to within specified range.
Spark plug gap: 0.7 – 0.8 mm (0.028 – 0.031 in.)
Spark plug torque specifications: Sparkplug: 28 N.m (2.8kg-m,20.0lb.-ft.)
When replacing the plug, confirm the spark plugs thread size and reach. If the spark plug reach is too short, carbon can potentially be deposited on the thread portion of the plug hone and result in possible engine damage.