Mercury 90 Operation Maintenance Installation Warranty Manual

2. Remove the spark plugs to inspect.
53782
3. Replace the spark plug if the electrode is worn; the insulator is rough,
cracked, broken, or blistered; or if the precious metal is not visible on the
spark plug electrode.
IMPORTANT: The color of the plug may not accurately reflect its condition. To
accurately diagnose a faulty plug, inspect the precious metal on the plug's
electrode. If no precious metal is visible, replace the plug.
a - Precious metal
4.
Set the spark plug gap. Refer to General Information ‑ Specifications.
27848
a
9381
MAINTENANCE
78 eng

Mercury 90 Specifications

General

Brand	Mercury
Model	90
Category	Outboard Motor
Language	English