Mercury Racing 500R Operation And Maintenance Manual page 116

4. Check the spark plug gap. Refer to General Information ‑ Specification.
a. All of the spark plugs should have the gap checked and corrected as
necessary before installation.
b. Measure the gap with a feeler gauge or pin gauge. Never use a
wedge‑type gap checking tool to inspect or to adjust the gap.
c. If an adjustment is necessary, do not pry or apply any force on the
center electrode. This is critical with any type of spark plug that has a
wear surface, such as platinum or iridium added to either the ground
electrode or the center electrode.
d. When it is necessary to widen the gap, use a tool that only pulls back
on the ground electrode without touching the center electrode, the
porcelain, or the wear portion of the ground electrode.
e. When it is necessary to close the gap, gently tap the plug ground
electrode on a hard surface.
5. Saltwater use—Apply Anti‑Seize Compound only onto the threads of the
spark plugs.
Description
Anti-Seize Compound
6. Before installing the spark plugs, remove any dirt on the spark plug seat
area. Install the plugs finger‑tight and then tighten an additional 1/4 turn or
tighten to the specified torque.
Description
Spark plug
7. Insert the spark plug boot into the valve cover. The boot is self‑aligning
with the spark plug.
MAINTENANCE
27848
Where Used
Spark plug threads
Nm
20
106
Part No.
92-898101389
lb‑in. lb‑ft
177 –
eng