Mercury 80 User Manual

• Inspect the outboard for tightness to the boat transom. If any looseness of
the outboard or mounting fasteners exist, tighten the outboard mounting
fasteners to the specified torque. When looking for signs of looseness,
look for loss of outboard transom bracket material or paint caused by
movement between the outboard mounting fasteners and the outboard
transom brackets. Also look for signs of movement between the outboard
transom brackets and the boat transom (lift plate/setback bracket).
Description Nm lb‑in. lb‑ft
Outboard mounting locknuts and
bolts ‑ standard boat transom
75 – 55
Outboard mounting locknuts and
bolts ‑ metal lift plates and setback
brackets
122 – 90
• Visually inspect the fuel system for deterioration or leaks.
• Check steering system for binding or loose components.
• Check propeller blades for damage.
AFTER EACH USE
• Flush out the outboard cooling system if operating in salt or polluted
water. Refer to 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 saltwater.
• If operating in saltwater, inspect the powerhead and powerhead
components for salt buildup. Refer to Cleaning Care for the Powerhead
(Saltwater Use).
EVERY 100 HOURS OF USE OR ONCE YEARLY, WHICHEVER
OCCURS FIRST
• 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. Refer to Changing Engine Oil.
• Inspect the thermostat visually for corrosion or a broken spring. Verify the
thermostat closes completely at room temperature. This item should be
serviced by an authorized dealer.
• Check low‑pressure fuel filter for contaminants. Replace filter if required.
Refer to Fuel System.
• Check the outboard mounting fasteners that secure the outboard to the
boat transom. Tighten the fasteners to the specified torque. This item
should be serviced by an authorized dealer.
MAINTENANCE
64 eng

Mercury 80 Specifications

General

Steering	Remote
Shaft Length	20 in (508 mm)
Gear Ratio	2.07:1
Horsepower	80 hp
Full Throttle RPM Range	5000-6000 RPM
Bore x Stroke	3.15 x 3.15 in (80 x 80 mm)