Mercury 20 User Manual

MAINTENANCE
42
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.
• Remote control models ‑ 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.
• Inspect and clean spark plugs. See Spark Plug Inspection and Replacement.
• Check fuel line filter for contaminants. See Fuel System.
• Check carburetor adjustments, if required. See Carburetor Adjustments.
• Check corrosion control anodes. Check more frequently when used in salt water. See Corrosion Control
Anodes.
• Drain and replace gearcase lubricant. See Gearcase Lubrication.
•
Lubricate splines on the driveshaft and shift shaft.
1.
• Electric start models ‑ Inspect battery. See Battery Inspection.
•
Remote control models ‑ Check control cable adjustments.
1.
• Remove engine deposits with Mercury Precision or Quicksilver Power Tune Engine Cleaner.
• Check tightness of bolts, nuts, and other fasteners.
• Clean fuel tank pick up filter.
EVERY 300 HOURS OF USE OR THREE YEARS
•
Replace water pump impeller (more often if overheating occurs or reduced water pressure is noted).
1.
BEFORE PERIODS OF STORAGE
• Refer to Storage procedure. See Storage section.
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.
Use a Mercury Precision or Quicksilver accessory (or equivalent) flushing attachment.
IMPORTANT: The engine must be run during flushing in order to open the thermostat and circulate water through
the water passages.
1. These items should be serviced by an authorized dealer.

Mercury 20 Specifications

General

Exhaust	Through Prop
Starting	Manual
Steering	Tiller
Shaft Length	15"
Horsepower	20 HP