Mercury Service Intervals

Mercury Optimax Inspection And Maintenance Schedule

BEFORE EACH USE

• Check that lanyard stop switch stops the engine.
• Visually inspect the fuel system for deterioration or leaks.
• Check outboard for tightness on transom.
• Check steering system for binding or loose components.

MAINTENANCE

• Visually check steering link rod fasteners for proper tightness. See Steering Link Rod Fasteners.
• Check propeller blades for damage.

AFTER EACH USE

• Flush out the outboard cooling system if operating in salt or polluted water. See Flushing the Cooling System.
• Wash off all salt deposits and flush out the exhaust outlet of the propeller and gearcase with fresh water if operating in salt water.

EVERY 100 HOURS OF USE OR ONCE YEARLY, WHICHEVER OCCURS FIRST

• Lubricate all lubrication points. Lubricate more frequently when used in salt water. See Lubrication Points.
• Replace spark plugs at first 100 hours or first year. After that, inspect spark plugs every 100 hours or once yearly. Replace spark plugs as needed. See Spark Plug Inspection and Replacement.
• Replace fuel filter. See Fuel System.
• Replace compressor air intake filter. See Compressor Air Intake Filter.
• Inspect alternator belt. See Alternator Belt Inspection.
• Check corrosion control anodes. Check more frequently when used in salt water. See Corrosion Control Anodes.
• Drain and replace gearcase lubricant. See Gearcase Lubrication.
• Check power trim fluid. See Checking Power Trim Fluid.
• Inspect battery. See Battery Inspection.
• Check control cable adjustments.1.
• Lubricate splines on the driveshaft and shift shaft.1.
• Check tightness of bolts, nuts, and other fasteners.

EVERY 300 HOURS OF USE OR THREE YEARS

• Replace water pump impeller (more often if overheating occurs or reduced water pressure is noted).

Flushing The Cooling System

Flush the internal water passages of the outboard with fresh water after each use in salt, polluted, or muddy water. This will help prevent a buildup of deposits from clogging the internal water passages.

Mercury 4-Storke Inspection And Maintenance Schedule

BEFORE EACH USE

• Check engine oil level. See Fuel & Oil - Checking and Adding Engine Oil.
• Check that lanyard stop switch stops the engine.
• Visually inspect the fuel system for deterioration or leaks.
• Check outboard for tightness on transom.
• Check steering system for binding or loose components.

MAINTENANCE

• Visually check steering link rod fasteners for proper tightness. See Steering Link Rod Fasteners.
• Check propeller blades for damage.

AFTER EACH USE

• Flush out the outboard cooling system if operating in salt or polluted water. See Flushing the Cooling System.
• Wash off all salt deposits and flush out the exhaust outlet of the propeller and gearcase with fresh water if operating in salt water.

EVERY 100 HOURS OF USE OR ONCE YEARLY, WHICHEVER OCCURS FIRST

• Lubricate all lubrication points. Lubricate more frequently when used in salt water. See Lubrication Points.
• Change engine oil and replace the oil filter. The oil should be changed more often when the engine is operated under adverse conditions such as extended trolling. See Changing Engine Oil.
• Replace spark plugs at first 100 hours or first year. After that, inspect spark plugs every 100 hours or once yearly. Replace spark plugs as needed. See Spark Plug Inspection and Replacement.
• Inspect thermostat visually for corrosion and broken spring. Make sure thermostat closes completely at room temperature.1.
• Check engine fuel filter for contaminants. See Fuel System.
• Check engine timing setup.1.
• Check corrosion control anodes. Check more frequently when used in salt water. See Corrosion Control Anodes.
• Drain and replace gear case lubricant. See Gearcase Lubrication.
• Lubricate splines on the drive shaft.1.
• Check and adjust valve clearance, if necessary.1.
• Check power trim fluid. See Checking Power Trim Fluid.
• Inspect battery. See Battery Inspection.
• Check control cable adjustments.1.
• Inspect timing belt. See Timing Belt Inspection.
• Check tightness of bolts, nuts, and other fasteners.

EVERY 300 HOURS OF USE OR THREE YEARS

• Replace water pump impeller (more often if overheating occurs or reduced water pressure is noted).1.
• 1. These items should be serviced by an authorized dealer.

Flushing The Cooling System

Flush the internal water passages of the outboard with fresh water after each use in salt, polluted, or muddy water. This will help prevent a buildup of deposits from clogging the internal water passages.

IMPORTANT: The engine must be run during flushing in order to open the thermostat and circulate water through the water passages.