Mercury 9.9 TwoStroke, 15 TwoStroke, 18 TwoStroke, 6 TwoStroke, 8 TwoStroke Maintance Manual

Operation

Maintenance

and

Installation

Manual

© 2017 Mercury Marine

9.9, 15, 18 TwoStroke

8M0133464 617 eng

eng

Welcome

You have selected one of the finest marine power packages available. It
incorporates numerous design features to ensure operating ease and durability.

With proper care and maintenance, you will enjoy using this product for many
boating seasons. To ensure maximum performance and carefree use, we ask
that you thoroughly read this manual.

The Operation and Maintenance Manual contains specific instructions for using
and maintaining your product. We suggest that this manual remain with the
product for ready reference whenever you are on the water.

Thank you for purchasing one of our products. We sincerely hope your boating
will be pleasant!

Mercury Marine, Fond du Lac, Wisconsin, U.S.A.

Name / function:

John Pfeifer, President,
Mercury Marine

Read This Manual Thoroughly

IMPORTANT: If you do not understand any portion of this manual, contact your
dealer. Your dealer can also provide a demonstration of actual starting and
operating procedures.

Notice

Throughout this publication, and on your power package, warnings, cautions,

and notices, accompanied by the International Hazard Symbol

!

, may be
used to alert the installer and user to special instructions concerning a
particular service or operation that may be hazardous if performed incorrectly
or carelessly. Observe them carefully.

These safety alerts alone cannot eliminate the hazards that they signal. Strict
compliance with these special instructions while performing the service, plus
common sense operation, are major accident prevention measures.

!

WARNING

Indicates a hazardous situation which, if not avoided, could result in death or
serious injury.

!

CAUTION

Indicates a hazardous situation which, if not avoided, could result in minor or
moderate injury.

eng i

NOTICE

Indicates a situation which, if not avoided, could result in engine or major
component failure.

IMPORTANT: Identifies information essential to the successful completion of
the task.

NOTE: Indicates information that helps in the understanding of a particular step
or action.

IMPORTANT: The operator (driver) is responsible for the correct and safe
operation of the boat, the equipment aboard, and the safety of all occupants
aboard. We strongly recommend that the operator read this Operation and
Maintenance Manual and thoroughly understand the operational instructions for
the power package and all related accessories before the boat is used.

!

WARNING

The engine exhaust from this product contains chemicals known to the state
of California to cause cancer, birth defects or other reproductive harm.

The serial numbers are the manufacturer’s keys to numerous engineering
details that apply to your Mercury Marine power package. When contacting
Mercury Marine about service, always specify model and serial numbers.

Descriptions and specifications contained herein were in effect at the time this
was approved for printing. Mercury Marine, whose policies are based on
continuous improvement, reserves the right to discontinue models at any time
or to change specifications or designs without notice and without incurring
obligation.

Warranty Message

The product you have purchased comes with a limited warranty from Mercury
Marine; the terms of the warranty are set forth in the Warranty Manual included
with the product. The Warranty Manual contains a description of what is
covered, what is not covered, the duration of coverage, how to best obtain
warranty coverage, important disclaimers and limitations of damages, and
other related information. Please review this important information.

Mercury Marine products are designed and manufactured to comply with our
own high quality standards, applicable industry standards and regulations, as
well as certain emissions regulations. At Mercury Marine every engine is
operated and tested before it is boxed for shipment to make sure that the
product is ready for use. In addition, certain Mercury Marine products are
tested in a controlled and monitored environment, for up to 10 hours of engine
run time, in order to verify and make a record of compliance with applicable
standards and regulations. All Mercury Marine product, sold as new, receives
the applicable limited warranty coverage, whether the engine participated in
one of the test programs described above or not.

ii eng

Copyright and Trademark Information

© MERCURY MARINE. All rights reserved. Reproduction in whole or in
part without permission is prohibited.

Alpha, Axius, Bravo One, Bravo Two, Bravo Three, Circle M with Waves Logo,
K‑planes, Mariner, MerCathode, MerCruiser, Mercury, Mercury with Waves
Logo, Mercury Marine, Mercury Precision Parts, Mercury Propellers, Mercury
Racing, MotorGuide, OptiMax, Quicksilver, SeaCore, Skyhook, SmartCraft,
Sport‑Jet, Verado, VesselView, Zero Effort, Zeus, #1 On the Water and We're
Driven to Win are registered trademarks of Brunswick Corporation. Pro XS is a
trademark of Brunswick Corporation. Mercury Product Protection is a registered
service mark of Brunswick Corporation.

Identification Records

Please record the following applicable information:

Outboard

Engine Model and Horsepower

Engine Serial Number

Gear Ratio

Propeller Number Pitch Diameter

Hull Identification Number (HIN) Purchase Date

Boat Manufacturer Boat Model Length

Exhaust Gas Emissions Certification Number (Europe Only)

eng iii

eng iv

General Information

Boater's Responsibilities..................................................................................... 1

Before Operating Your Outboard........................................................................ 1

Boat Horsepower Capacity................................................................................. 1

Outboard Remote Control Models ..................................................................... 2

Remote Steering Notice......................................................................................3

Lanyard Stop Switch........................................................................................... 3

Protecting People in the Water........................................................................... 6

Passenger Safety Message ‑ Pontoon Boats and Deck Boats...........................6

Wave and Wake Jumping................................................................................... 8

Impact with Underwater Hazards........................................................................9

Safety Instructions for Hand‑Tilled Outboards.................................................. 10

Exhaust Emissions........................................................................................... 10

Selecting Accessories for Your Outboard......................................................... 12

Safe Boating Recommendations...................................................................... 12

Recording Serial Number................................................................................. 15

Model Year Production Code............................................................................15

Specifications....................................................................................................17

Component Identification.................................................................................. 20

Associated Parts............................................................................................... 25

Transporting

Removing the Motor......................................................................................... 26

Carrying the Motor............................................................................................ 26

Storing the Motor.............................................................................................. 26

Trailering Boat/Outboard.................................................................................. 27

Transporting Portable Fuel Tanks.................................................................... 28

Fuel and Oil

Fuel Requirements........................................................................................... 29

Oil Recommendation........................................................................................ 30

Mixing Fuel and Oil........................................................................................... 30

Engine Break‑In................................................................................................ 31

Filling Fuel Tank............................................................................................... 31

eng v

Features and Controls

Remote Control Features................................................................................. 32

Tilt Up and Tilt Down........................................................................................ 32

Shallow Water Operation.................................................................................. 34

Trim Angle Adjustment..................................................................................... 35

Steering Friction Adjustment.............................................................................36

Throttle Grip Turning Friction Adjustment......................................................... 37

Trim Tab Adjustment........................................................................................ 37

Operation

Prestarting Check List.......................................................................................40

Operating in Freezing Temperatures................................................................ 40

Operating in Saltwater or Polluted Water......................................................... 40

Operating at High Elevations............................................................................ 41

Operating Outboard as an Auxiliary Engine..................................................... 41

Prestarting Instructions..................................................................................... 41

Engine Break‑In Procedure.............................................................................. 42

Warming Up the Engine....................................................................................43

Starting the Engine........................................................................................... 44

Gear Shifting..................................................................................................... 47

Stopping the Engine......................................................................................... 49

Emergency Starting.......................................................................................... 51

Maintenance

Cleaning Care Recommendations.................................................................... 53

Outboard Care.................................................................................................. 54

Inspection and Maintenance Schedule ............................................................ 54

Flushing the Cooling System............................................................................ 56

Top Cowl Removal and Installation.................................................................. 57

Battery Inspection ............................................................................................ 58

Fuel System...................................................................................................... 58

Exterior Care.....................................................................................................60

Fuse Replacement ‑ Electric Start Remote Control Models............................. 60

Replacing the Anodes.......................................................................................61

Propeller Replacement..................................................................................... 62

Spark Plug Inspection and Replacement..........................................................65

Lubrication Points............................................................................................. 66

Changing Gear Oil............................................................................................ 66

Submerged Outboard....................................................................................... 67

vi eng

Storage

Preseason Check............................................................................................. 68

Storage Preparation..........................................................................................68

Protecting External Outboard Components...................................................... 69

Protecting Internal Engine Components........................................................... 69

Gearcase.......................................................................................................... 69

Positioning Outboard for Storage..................................................................... 69

Battery Storage................................................................................................. 70

Troubleshooting

Starter Motor Will Not Crank the Engine (Electric Start Models)...................... 71

Engine Will Not Start.........................................................................................71

Engine Runs Erratically.................................................................................... 71

Performance Loss.............................................................................................72

Battery Will Not Hold Charge............................................................................ 72

Installation

Mercury Marine Validated Engine Mounting Hardware.................................... 73

Installing Outboard............................................................................................73

Installing the Remote Control Devices..............................................................75

Wire Color Code Abbreviations........................................................................ 80

Battery Installation............................................................................................ 81

Propeller Selection............................................................................................82

Accessories

Propeller Table................................................................................................. 83

Accessories...................................................................................................... 84

Wiring Diagrams

MH Models........................................................................................................86

EH Models........................................................................................................ 88

E Models........................................................................................................... 90

Single Remote Control Box.............................................................................. 92

eng vii

Owner Service Assistance

Service Assistance........................................................................................... 94

Ordering Literature............................................................................................96

Maintenance Log

Maintenance Log.............................................................................................. 98

viii eng

Boater's Responsibilities

The operator (driver) is responsible for the correct and safe operation of the
boat and the safety of its occupants and general public. It is strongly
recommended that each operator read and understand this entire manual
before operating the outboard.

Be sure that at least one additional person onboard is instructed in the basics
of starting and operating the outboard and boat handling in case the driver is
unable to operate the boat.

Before Operating Your Outboard

Read this manual carefully. Learn how to operate your outboard properly. If you
have any questions, contact your dealer.

Safety and operating information that is practiced, along with using good
common sense, can help prevent personal injury and product damage.

This manual as well as safety labels posted on the outboard use the following
safety alerts to draw your attention to special safety instructions that should be
followed.

!

WARNING

Indicates a hazardous situation which, if not avoided, could result in death or
serious injury.

!

CAUTION

Indicates a hazardous situation which, if not avoided, could result in minor or
moderate injury.

NOTICE

Indicates a situation which, if not avoided, could result in engine or major
component failure.

Boat Horsepower Capacity

!

WARNING

Exceeding the boat's maximum horsepower rating can cause serious injury
or death. Overpowering the boat can affect boat control and flotation
characteristics or break the transom. Do not install an engine that exceeds
the boat's maximum power rating.

GENERAL INFORMATION

eng 1

Do not overpower or overload your boat. Most boats will carry a required
capacity plate indicating the maximum acceptable power and load as
determined by the manufacturer following certain federal guidelines. If in doubt,
contact your dealer or the boat manufacturer.

U.S. COAST GUARD CAP ACITY

MAXIMUM HORSEPOWER XXX

MAXIMUM PERSON
CAPACITY (POUNDS)

XXX

MAXIMUM WEIGHT
CAPACITY

XXX

26777

Outboard Remote Control Models

The remote control connected to your outboard must be equipped with a start
in neutral only protection device. This prevents the engine from starting when
the shift is actuated in any position other than neutral.

!

WARNING

Starting the engine with the drive in gear can cause serious injury or death.
Never operate a boat that does not have a neutral‑safety‑protection device.

N

63103

GENERAL INFORMATION

2 eng

Remote Steering Notice

!

WARNING

Improper fasteners or improper installation procedures can result in
loosening or disengagement of the steering link rod. This can cause a
sudden, unexpected loss of boat control, resulting in serious injury or death
due to occupants being thrown within or out of the boat. Always use required
components and follow instructions and torque procedures.

The steering link rod that connects the steering cable to the engine must be
fastened utilizing self‑locking nuts. These self‑locking nuts must never be
replaced with common nuts (nonlocking) as they will work loose and vibrate off,
freeing the link rod to disengage.

a - Self‑locking nuts

Lanyard Stop Switch

The purpose of a lanyard stop switch is to turn off the engine when the operator
moves far enough away from the operator's position (as in accidental ejection
from the operator's position) to activate the switch. Tiller handle outboards and
some remote control units are equipped with a lanyard stop switch. A lanyard
stop switch can be installed as an accessory ‑ generally on the dashboard or
side adjacent to the operator's position.

A decal near the lanyard stop switch is a visual reminder for the operator to
attach the lanyard to their personal flotation device (PFD) or wrist.

a

3018

GENERAL INFORMATION

eng 3

The lanyard cord is usually 122–152 cm (4–5 feet) in length when stretched out,
with an element on one end made to be inserted into the switch and a clip on
the other end for attaching to the operator's PFD or wrist. The lanyard is coiled
to make its at‑rest condition as short as possible to minimize the likelihood of
lanyard entanglement with nearby objects. Its stretched‑out length is made to
minimize the likelihood of accidental activation should the operator choose to
move around in an area close to the normal operator's position. If it is desired
to have a shorter lanyard, wrap the lanyard around the operator's wrist or leg,
or tie a knot in the lanyard.

a - Lanyard cord clip
b - Lanyard decal
c - Lanyard stop switch

Read the following Safety Information before proceeding.
Important Safety Information: The purpose of a lanyard stop switch is to stop

the engine when the operator moves far enough away from the operator's
position to activate the switch. This would occur if the operator accidentally falls
overboard or moves within the boat a sufficient distance from the operator's
position. Falling overboard and accidental ejections are more likely to occur in
certain types of boats such as low sided inflatables, bass boats, high
performance boats, and light, sensitive handling fishing boats operated by a
hand tiller. Falling overboard and accidental ejections are also likely to occur as
a result of poor operating practices such as sitting on the back of the seat or
gunwale at planing speeds, standing at planing speeds, sitting on elevated
fishing boat decks, operating at planing speeds in shallow or obstacle infested
waters, releasing your grip on a steering wheel or tiller handle that is pulling in
one direction, drinking alcohol or consuming drugs, or daring high speed boat
maneuvers.

c

a

b

53910

OFF

RUN

ATTACH LANYARD

GENERAL INFORMATION

4 eng

While activation of the lanyard stop switch will stop the engine immediately, a
boat will continue to coast for some distance depending upon the velocity and
degree of any turn at shut down. However, the boat will not complete a full
circle. While the boat is coasting, it can cause injury to anyone in the boat's
path as seriously as the boat would when under power.

We strongly recommend that other occupants be instructed on proper starting
and operating procedures should they be required to operate the engine in an
emergency (if the operator is accidentally ejected).

!

WARNING

If the operator falls out of the boat, stop the engine immediately to reduce the
possibility of serious injury or death from being struck by the boat. Always
properly connect the operator to the stop switch using a lanyard.

!

WARNING

Avoid serious injury or death from deceleration forces resulting from
accidental or unintended stop switch activation. The boat operator should
never leave the operator's station without first disconnecting the stop switch
lanyard from the operator.

Accidental or unintended activation of the switch during normal operation is
also a possibility. This could cause any, or all, of the following potentially
hazardous situations:

• Occupants could be thrown forward due to unexpected loss of forward
motion ‑ a particular concern for passengers in the front of the boat who
could be ejected over the bow and possibly struck by the gearcase or
propeller.

• Loss of power and directional control in heavy seas, strong current, or
high winds.

• Loss of control when docking.

KEEP THE LANYARD STOP SWITCH AND LANYARD CORD IN GOOD
OPERATING CONDITION

Before each use, check to ensure the lanyard stop switch works properly. Start
the engine and stop it by pulling the lanyard cord. If the engine does not stop,
have the switch repaired before operating the boat.

Before each use, visually inspect the lanyard cord to ensure it is in good
working condition and that there are no breaks, cuts, or wear to the cord.
Check that the clips on the ends of the cord are in good condition. Replace any
damaged or worn lanyard cords.

GENERAL INFORMATION

eng 5

Protecting People in the Water

WHILE YOU ARE CRUISING

It is very difficult for a person standing or floating in the water to take quick
action to avoid a boat heading in his/her direction, even at slow speed.

21604

Always slow down and exercise extreme caution any time you are boating in an
area where there might be people in the water.

Whenever a boat is moving (coasting) and the outboard gear shift is in neutral
position, there is sufficient force by the water on the propeller to cause the
propeller to rotate. This neutral propeller rotation can cause serious injury.

WHILE THE BOAT IS STATIONARY

!

WARNING

A spinning propeller, a moving boat, or any solid device attached to the boat
can cause serious injury or death to swimmers. Stop the engine immediately
whenever anyone in the water is near your boat.

Shift the outboard into neutral and shut off the engine before allowing people to
swim or be in the water near your boat.

Passenger Safety Message ‑ Pontoon Boats and Deck Boats

Whenever the boat is in motion, observe the location of all passengers. Do not
allow any passengers to stand or use seats other than those designated for
traveling faster than idle speed. A sudden reduction in boat speed, such as
plunging into a large wave or wake, a sudden throttle reduction, or a sharp
change of boat direction, could throw them over the front of the boat. Falling
over the front of the boat between the two pontoons will position them to be run
over by the outboard.

BOATS HAVING AN OPEN FRONT DECK

No one should ever be on the deck in front of the fence while the boat is in
motion. Keep all passengers behind the front fence or enclosure.

GENERAL INFORMATION

6 eng

Persons on the front deck could easily be thrown overboard or persons
dangling their feet over the front edge could get their legs caught by a wave
and pulled into the water.

26782

!

WARNING

Sitting or standing in an area of the boat not designed for passengers at
speeds above idle can cause serious injury or death. Stay back from the front
end of deck boats or raised platforms and remain seated while the boat is in
motion.

BOATS WITH FRONT MOUNTED, RAISED PEDESTAL FISHING SEATS

Elevated fishing seats are not intended for use when the boat is traveling faster
than idle or trolling speed. Sit only in seats designated for traveling at faster
speeds.

Any unexpected, sudden reduction in boat speed could result in the elevated
passenger falling over the front of the boat.

26783

GENERAL INFORMATION

eng 7

Wave and Wake Jumping

Operating recreational boats over waves and wake is a natural part of boating.
However, when this activity is done with sufficient speed to force the boat hull
partially or completely out of the water, certain hazards arise, particularly when
the boat enters the water.

26784

The primary concern is the boat changing direction while in the midst of the
jump. In such case, the landing may cause the boat to veer violently in a new
direction. Such a sharp change in direction can cause occupants to be thrown
out of their seats, or out of the boat.

!

WARNING

Wave or wake jumping can cause serious injury or death from occupants
being thrown within or out of the boat. Avoid wave or wake jumping whenever
possible.

There is another less common hazardous result from allowing your boat to
launch off a wave or wake. If the bow of your boat pitches down far enough
while airborne, upon water contact it may penetrate under the water surface
and submarine for an instant. This will bring the boat to a nearly instantaneous
stop and can send the occupants flying forward. The boat may also steer
sharply to one side.

GENERAL INFORMATION

8 eng

Impact with Underwater Hazards

Reduce speed and proceed with caution whenever you drive a boat in shallow
water areas, or in areas where you suspect underwater obstacles may exist
which could be struck by the outboard or the boat bottom. The most important

thing you can do to help reduce injury or impact damage from striking a
floating or underwater object is to control the boat speed. Under these
conditions, boat speed should be kept to a minimum planing speed of
24 to 40 km/h (15 to 25 mph).

26785

Striking a floating or underwater object could result in an infinite number of
situations. Some of these situations could result in the following:

• Part of the outboard or the entire outboard could break loose and fly into
the boat.

• The boat could move suddenly in a new direction. Such a sharp change in
direction can cause occupants to be thrown out of their seats or out of the
boat.

• A rapid reduction in speed. This will cause occupants to be thrown
forward, or even out of the boat.

• Impact damage to the outboard and/or boat.

Keep in mind, the most important thing you can do to help reduce injury or
impact damage during an impact is control the boat speed. Boat speed should
be kept to a minimum planing speed when driving in waters known to have
underwater obstacles.

After striking a submerged object, stop the engine as soon as possible and
inspect it for any broken or loose parts. If damage is present or suspected, the
outboard should be taken to an authorized dealer for a thorough inspection and
necessary repair.

The boat should also be checked for any hull fractures, transom fractures, or
water leaks.

Operating a damaged outboard could cause additional damage to other parts
of the outboard, or could affect control of the boat. If continued running is
necessary, do so at greatly reduced speeds.

GENERAL INFORMATION

eng 9

!

WARNING

Operating a boat or engine with impact damage can result in product
damage, serious injury, or death. If the vessel experiences any form of
impact, have an authorized Mercury Marine dealer inspect and repair the
vessel or power package.

Safety Instructions for Hand‑Tilled Outboards

No person or cargo should occupy the area directly in front of the outboard
while the boat is in motion. If an underwater obstacle is struck, the outboard will
tilt up and could seriously injure anyone occupying this area.

MODELS WITH CLAMP SCREWS:

Some outboards come with transom bracket clamp screws. The use of clamp
bracket screws alone, is insufficient to properly and safely secure the outboard
to the transom. Proper installation of the outboard includes bolting the engine to
the boat through the transom. Refer to Installation ‑ Installing Outboard for
more complete installation information.

!

WARNING

Failure to correctly fasten the outboard could result in the outboard propelling
off the boat transom resulting in property damage, serious injury, or death.
Before operation, the outboard must be correctly installed with the required
mounting hardware.

If an obstacle is struck at planing speed and the outboard is not securely
fastened to the transom, it is possible the outboard could lift off the transom
and land in the boat.

Exhaust Emissions

BE ALERT TO CARBON MONOXIDE POISONING

Carbon monoxide (CO) is a deadly gas that is present in the exhaust fumes of
all internal combustion engines, including the engines that propel boats, and
the generators that power boat accessories. By itself, CO is odorless, colorless,
and tasteless, but if you can smell or taste engine exhaust, you are inhaling
CO.

Early symptoms of carbon monoxide poisoning, which are similar to the
symptoms of seasickness and intoxication, include headache, dizziness,
drowsiness, and nausea.

GENERAL INFORMATION

10 eng

!

WARNING

Inhaling engine exhaust gases can result in carbon monoxide poisoning,
which can lead to unconsciousness, brain damage, or death. Avoid exposure
to carbon monoxide.

Stay clear from exhaust areas when engine is running. Keep the boat
well‑ventilated while at rest or underway.

STAY CLEAR OF EXHAUST AREAS

41127

co

co

co

co

co

co

co

co

co

co

co

co

co

co

co

co

co

co

co

co

Engine exhaust gases contain harmful carbon monoxide. Avoid areas of
concentrated engine exhaust gases. When engines are running, keep
swimmers away from the boat, and do not sit, lie, or stand on swim platforms or
boarding ladders. While underway, do not allow passengers to be positioned
immediately behind the boat (platform dragging, teak/body surfing). This
dangerous practice not only places a person in an area of high engine exhaust
concentration, but also subjects them to the possibility of injury from the boat
propeller.

GOOD VENTILATION

Ventilate the passenger area, open side curtains or forward hatches to remove
fumes.

Example of desired air flow through the boat:

21622

POOR VENTILATION

Under certain running and/or wind conditions, permanently enclosed or canvas
enclosed cabins or cockpits with insufficient ventilation may draw in carbon
monoxide. Install one or more carbon monoxide detectors in your boat.

Although the occurrence is rare, on a very calm day, swimmers and
passengers in an open area of a stationary boat that contains, or is near, a
running engine may be exposed to a hazardous level of carbon monoxide.

GENERAL INFORMATION

eng 11

1. Examples of poor ventilation while the boat is stationary:

a - Operating the engine when the boat is moored in a confined space
b - Mooring close to another boat that has its engine operating

2. Examples of poor ventilation while the boat is moving:

a - Operating the boat with the trim angle of the bow too high
b - Operating the boat with no forward hatches open (station wagon effect)

Selecting Accessories for Your Outboard

Genuine Mercury Precision or Quicksilver Accessories have been specifically
designed and tested for your outboard. These accessories are available from
Mercury Marine dealers.

IMPORTANT: Check with your dealer before installing accessories. The misuse
of approved accessories or the use of nonapproved accessories can damage
the product.

Some accessories not manufactured or sold by Mercury Marine are not
designed to be safely used with your outboard or outboard operating system.
Acquire and read the installation, operation and maintenance manuals for all
your selected accessories.

Safe Boating Recommendations

To safely enjoy the waterways, familiarize yourself with local and all other
governmental boating regulations and restrictions and consider the following
suggestions.

Know and obey all nautical rules and laws of the waterways.

21626

a

b

a

b

21628

GENERAL INFORMATION

12 eng

• We recommend that all powerboat operators complete a boating safety
course. In the U.S., the U.S. Coast Guard Auxiliary, the Power Squadron,
the Red Cross, and your state or provincial boating law enforcement
agency provide courses. For more information in the U.S., call the Boat
U.S. Foundation at 1‑800‑336‑BOAT (2628).

Perform safety checks and required maintenance.

• Follow a regular schedule and ensure that all repairs are properly made.

Check safety equipment onboard.

• Here are some suggestions of the types of safety equipment to carry
when boating:

Approved fire extinguishers

Signal devices: flashlight, rockets or flares, flag, and whistle or horn

Tools necessary for minor repairs

Anchor and extra anchor line

Manual bilge pump and extra drain plugs

Drinking water

Radio

Paddle or oar

Spare propeller, thrust hubs, and an appropriate wrench

First aid kit and instructions

Waterproof storage containers

Spare operating equipment, batteries, bulbs, and fuses

Compass and map or chart of the area

Personal flotation device (one per person onboard)

Watch for signs of weather change and avoid foul weather and rough‑sea
boating.

Tell someone where you are going and when you expect to return.

Passenger boarding.

• Stop the engine whenever passengers are boarding, unloading, or are
near the back (stern) of the boat. Shifting the drive unit into neutral is not
sufficient.

Use personal flotation devices.

• Federal law requires that there be a U.S. Coast Guard‑approved life
jacket (personal flotation device), correctly sized and readily accessible
for every person onboard, plus a throwable cushion or ring. We strongly
advise that everyone wear a life jacket at all times while in the boat.

Prepare other boat operators.

GENERAL INFORMATION

eng 13

• Instruct at least one person onboard in the basics of starting and
operating the engine and boat handling in case the driver becomes
disabled or falls overboard.

Do not overload your boat.

• Most boats are rated and certified for maximum load (weight) capacities
(refer to your boat's capacity plate). Know your boat's operating and
loading limitations. Know if your boat will float if it is full of water. When in
doubt, contact your authorized Mercury Marine dealer or the boat
manufacturer.

Ensure that everyone in the boat is properly seated.

• Do not allow anyone to sit or ride on any part of the boat that was not
intended for such use. This includes the backs of seats, gunwales,
transom, bow, decks, raised fishing seats, and any rotating fishing seat.
Passengers should not sit or ride anywhere that sudden unexpected
acceleration, sudden stopping, unexpected loss of boat control, or sudden
boat movement could cause a person to be thrown overboard or into the
boat. Ensure that all passengers have a proper seat and are in it before
any boat movement.

Never operate a boat while under the influence of alcohol or drugs. It is
the law.

• Alcohol or drugs can impair your judgment and greatly reduce your ability
to react quickly.

Know your boating area and avoid hazardous locations.

Be alert.

• The operator of the boat is responsible by law to maintain a proper
lookout by sight and hearing. The operator must have an unobstructed
view particularly to the front. No passengers, load, or fishing seats should
block the operator's view when the boat is above idle or planing transition
speed. Watch out for others, the water, and your wake.

Never drive your boat directly behind a water‑skier.

• Your boat traveling at 40 km/h (25 mph) will overtake a fallen skier who is
61 m (200 ft) in front of you in five seconds.

Watch fallen skiers.

• When using your boat for waterskiing or similar activities, always keep a
fallen or down skier on the operator's side of the boat while returning to
attend to the skier. The operator should always have the down skier in
sight and never back up to the skier or anyone in the water.

Report accidents.

GENERAL INFORMATION

14 eng

• Boat operators are required by law to file a boating accident report with
their state boating law enforcement agency when their boat is involved in
certain boating accidents. A boating accident must be reported if 1) there
is loss of life or probable loss of life, 2) there is personal injury requiring
medical treatment beyond first aid, 3) there is damage to boats or other
property where the damage value exceeds $500.00, or 4) there is
complete loss of the boat. Seek further assistance from local law
enforcement.

Recording Serial Number

It is important to record the serial number and other important information for
future reference.

Please record the serial number of the engine as indicated (on the lower engine
cover and the cylinder block) in the space below. This number will come in
handy in the event of theft and it can help you to quickly identify the product
type.

Serial number:
Model year:
Model designation:
Year manufactured:
Certified Europe Insignia (as applicable):

Model Year Production Code

The serial number decal lists the year of manufacture as an alpha code. This
code can be deciphered into a corresponding number utilizing the following
table.

XXXXXXXXX

XXXXXXXX

XXXX

AG

62972

Serial number decal alpha code

GENERAL INFORMATION

eng 15

Model Year Manufactured Code
Alpha Production Code A B C D E F G H K X
Corresponding Number 1 2 3 4 5 6 7 8 9 0

Examples:

• XX = 2000

• HK = 2089

• AG = 2017

GENERAL INFORMATION

16 eng

Specifications

MODEL 9.9 MH 9.9 EH

Overall length 869 mm (34.2 in.)
Overall width 345 mm (13.6 in.)

Overall height

S = 1067 mm (42.0 in.)
L = 1194 mm (47.0 in.)

XL = 1321 mm (52.0 in.)

Transom height

S = 435 mm (17.1 in.)
L = 562 mm (22.1 in.)

XL = 689 mm (27.1 in.)

Weight

S 41.0 kg (90.3 lb) 44.0 kg (97.0 lb)
L 42.0 kg (92.6 lb) 45.0 kg (99.2 lb)

XL 43.0 kg (94.8 lb) 46.0 kg (101.4 lb)
Output 7.3 kW
Maximum operating

range

4500–5300 RPM

Number of cylinders 2
Displacement 247 cc
Bore x stroke 55 x 52 mm (2.1 x 2.0 in.)
Exhaust system Through‑the‑hub exhaust
Lubrication system Engine oil mixed gasoline
Cooling system Thermostat controlled
Starting system Manual Electric with manual backup
Ignition Flywheel magneto CDI

Spark plugs

NGK B7HS‑10/BR7HS‑10 or Champion L82C/

RL82C

gap 1.0 mm (0.039 in.)

Trim system Manual, 6 positions

Engine oil mixing ratio

Mercury/Quicksilver 2‑Stroke engine oil: Unleaded

gasoline

1:50

Gear oil

Mercury/Quicksilver gear oil API GL5, SAE #80–90

approximately 370 mL (12.5 oz)
Fuel tank capacity 25 Liter (6.6 US gal)
Gear reduction ratio 13:24 (1.84:1)

GENERAL INFORMATION

eng 17

MODEL 15 MH 15 EH

Overall length 869 mm (34.2 in.)
Overall width 345 mm (13.6 in.)

Overall height

S = 1067 mm (42.0 in.)
L = 1194 mm (47.0 in.)

XL = 1321 mm (52.0 in.)

Transom height

S = 435 mm (17.1 in.)

L = 562 mm (22.1 in.)

XL = 689 mm (27.1 in.)

Weight

S 41.0 kg (90.3 lb) 44.0 kg (97.0 lb)
L 42.0 kg (92.6 lb) 45.0 kg (99.2 lb)

XL 43.0 kg (94.8 lb) 46.0 kg (101.4 lb)
Output 11.0 kW
Maximum operating

range

5200–5800 RPM

Number of cylinders 2
Displacement 294 cc
Bore x stroke 60 x 52 mm (2.3 x 2.0 in.)
Exhaust system Through‑the‑hub exhaust
Lubrication system Engine oil mixed gasoline
Cooling system Thermostat controlled
Starting system Manual Electric with manual backup
Ignition Flywheel magneto CDI

Spark plugs

NGK B7HS‑10/BR7HS‑10 or Champion L82C/

RL82C

gap 1.0 mm (0.039 in.)

Trim system Manual, 6 positions

Engine oil mixing ratio

Mercury/Quicksilver 2‑Stroke engine oil: Unleaded

gasoline

1:50

Gear oil

Mercury/Quicksilver gear oil API GL5, SAE #80–90

approximately 370 mL (12.5 oz)
Fuel tank capacity 25 Liter (6.6 US gal)
Gear reduction ratio 13:24 (1.84:1)

GENERAL INFORMATION

18 eng

MODEL 18 MH

Overall length 869 mm (34.2 in.)
Overall width 345 mm (13.6 in.)

Overall height

S = 1067 mm (42.0 in.)
L = 1194 mm (47.0 in.)

XL = 1321 mm (52.0 in.)

Transom height

S = 435 mm (17.1 in.)
L = 562 mm (22.1 in.)

XL = 689 mm (27.1 in.)

Weight

S 41.0 kg (90.3 lb)
L 42.0 kg (92.6 lb)

XL 43.0 kg (94.8 lb)
Output 13.2 kW
Max operating range 5200–5800 RPM
Number of cylinders 2
Displacement 294 cc
Bore x stroke 60 x 52 mm (2.3 x 2.0 in.)
Exhaust system Through‑the‑hub exhaust
Lubrication system Engine oil mixed gasoline
Cooling system Thermostat controlled
Starting system Manual
Ignition Flywheel magneto CDI

Spark plugs

NGK B7HS‑10/BR7HS‑10 or Champion L82C/RL82C

gap 1.0 mm (0.039 in.)

Trim system Manual, 6 positions

Engine oil mixing
ratio

Mercury/Quicksilver 2‑Stroke engine oil: Unleaded

gasoline

1:50

Gear oil

Mercury/Quicksilver gear oil API GL5, SAE #80–90

approximately 370 mL (12.5 oz)
Fuel tank capacity 25 Liter (6.6 US gal)
Gear reduction ratio 13:24 (1.84:1)

GENERAL INFORMATION

eng 19

Component Identification

40465

1

2

3

4

5

6

8

9

10

11

15

16

17

18

19

21

22

23

24

12

13

14

25

27

28 2926

30

20

7

GENERAL INFORMATION

20 eng

MH Models

1 - Tilt handle
2 - Top cowl
3 - Bottom cowl
4 - Reverse lock lever
5 - Water pump indicator hole
6 - Driveshaft housing
7 - Water strainer
8 - Anti‑ventilation plate
9 - Anode/trim tab
10 - Secondary water intake
11 - Propeller
12 - Oil drain plug (upper)
13 - Water plug
14 - Oil drain plug (lower)
15 - Starter handle
16 - Shift lever
17 - Stop switch
18 - Starter switch button
19 - Choke knob
20 - Fuel hose connector
21 - Throttle grip
22 - Clamp screws
23 - Transom brackets
24 - Thrust rod
25 - Primer bulb
26 - Fuel pickup elbow
27 - Fuel connector
28 - Fuel tank cap
29 - Air vent screw
30 - Fuel tank

GENERAL INFORMATION

eng 21

40466

1

2

3

4

5

6

8

9

10

11

15

16

17

18

19

21

22

23

24

12

13

14

26 28 29

30

27

31

20

7

25

GENERAL INFORMATION

22 eng

EH Models

1 - Tilt handle
2 - Top cowl
3 - Bottom cowl
4 - Reverse lock lever
5 - Water pump indicator hole
6 - Driveshaft housing
7 - Water strainer
8 - Anti‑ventilation plate
9 - Anode/trim tab
10 - Secondary water intake
11 - Propeller
12 - Oil drain plug (upper)
13 - Water plug
14 - Oil drain plug (lower)
15 - Starter handle
16 - Shift lever
17 - Stop switch
18 - Starter switch button
19 - Choke knob
20 - Fuel hose connector
21 - Throttle grip
22 - Clamp screws
23 - Transom brackets
24 - Thrust rod
25 - Battery cables
26 - Primer bulb
27 - Fuel pickup elbow
28 - Fuel connector
29 - Fuel tank cap
30 - Air vent screw
31 - Fuel tank

GENERAL INFORMATION

eng 23

40467

1

2

3

4

5

6

8

9

10

11

15

16

17

18

19

21

22

23

24

12

13

14

26 28 29

30

27

31

20

7

25

32

33

34

35

GENERAL INFORMATION

24 eng

E Models

1 - Tilt handle
2 - Top cowl
3 - Bottom cowl
4 - Reverse lock lever
5 - Water pump indicator hole
6 - Driveshaft housing
7 - Water strainer
8 - Anti‑ventilation plate
9 - Anode/trim tab
10 - Secondary water intake
11 - Propeller
12 - Oil drain plug (upper)
13 - Water plug
14 - Oil drain plug (lower)
15 - Starter handle
16 - Shift lever
17 - Stop switch (optional)

18 - Starter switch button
19 - Choke knob
20 - Fuel hose connector
21 - Throttle grip
22 - Clamp screws
23 - Transom brackets
24 - Thrust rod
25 - Battery cables
26 - Primer bulb
27 - Fuel pickup elbow
28 - Fuel connector
29 - Fuel tank cap
30 - Air vent screw
31 - Fuel tank
32 - Remote control box
33 - Main switch
34 - Lanyard stop switch
35 - Harness assembly

Associated Parts

Name

Qty. Dimensions

Service tools

Tool bag 1
Pliers 1
Socket wrench 1 10 x 13 mm
Socket wrench 1 21 mm
Socket wrench

handle

1

Screwdriver 1
Screwdriver handle 1

Spare parts

Starter rope 1 1000 mm

Spark plug 1

NGK B7HS‑10 or

Champion L82C

(gap: 1.0 mm)

Cotter pin 1

Other*

Fuel tank 1
Primer bulb 1 set
Remote control box 1 set E Models only
Remote control

attachment

1 set E Models only

* Not included as standard accessories in some markets.

GENERAL INFORMATION

eng 25

Removing the Motor

1. Stop the engine.

2. Disconnect the fuel connector, the remote control cable, the battery
cables, bracket fixing bolts and nuts, etc. from the motor.

3. Remove the motor from the hull and completely drain the water from the
gear housing. Be sure to keep the engine higher than the propeller
whenever you carry the motor.

Carrying the Motor

Be sure to keep the motor in a vertical position whenever you carry the motor.

39485

NOTE: If you carry the motor in a horizontal position, keep the powerhead
higher than the propeller.

IMPORTANT: Beware of explosion danger. Spilled and vapored gasoline may
easily catch fire and explode. Be sure to fully discharge gasoline from the
carburetors when transporting the engine. Wipe off spilled gasoline with a rag.

Storing the Motor

Keep the motor in a vertical position whenever you store the motor.

NOTE: If you store the motor in a horizontal position, lay the motor down on the
ground with the handles facing upward.

40803

TRANSPORTING

26 eng

Trailering Boat/Outboard

The boat should be trailered with the outboard tilted down in a vertical (normal
running) position, fully down.

NOTE: Trailering in the tilted position may cause damage to the motor, boat,
etc. If trailering with the motor fully down is not available (the gearcase skeg is
too close to the road in a vertical position), secure the motor using a device like
a transom saver bar in the tilted position.

39486

Shift the outboard to the forward gear. This prevents the propeller from
spinning freely.

If additional ground clearance is required, the outboard should be tilted up
using an accessory outboard support device. Refer to your local dealer for
recommendations. Additional clearance may be required for railroad crossings,
driveways, and trailer bouncing.

IMPORTANT: The tilt lock and shallow water drive feature (tiller handle models)
on the outboard are not intended to support the outboard in the tilted position
when trailering.

TRANSPORTING

eng 27

Transporting Portable Fuel Tanks

!

WARNING

Avoid serious injury or death from a gasoline fire or explosion. Follow the
transporting instructions supplied with the portable fuel tank. Transport the
fuel tank in a well ventilated area away from open flame or sparks.

MANUAL VENTING TYPE FUEL TANK

Close the fuel tank air vent when transporting tank. This will prevent escape of
fuel or vapors from tank.

26793

AUTO-VENTING TYPE FUEL TANK

1. Disconnect the remote fuel line from tank. This will close the air vent and
prevent escape of fuel or vapors from tank.

2. Install tether cap over the fuel line connector stem. This will protect the
connector stem from being accidentally pushed‑in, allowing fuel or vapor
to escape.

a - Connector stem
b - Tether cap

F

a

b

26794

TRANSPORTING

28 eng

Fuel Requirements

IMPORTANT: Use of improper gasoline can damage your engine. Engine
damage resulting from the use of improper gasoline is considered misuse
of the engine and will not be covered under the limited warranty.

FUEL RATINGS

Mercury outboard engines will operate satisfactorily with any major brand of
unleaded gasoline that meets the following specifications:

USA and Canada ‑ A posted pump octane rating of 87 (R+M)/2, minimum, for
most models. Premium gasoline 91 (R+M)/2 octane is also acceptable for most
models. Do not use leaded gasoline.

Outside USA and Canada ‑ A posted pump octane rating of 91 RON,
minimum, for most models. Premium gasoline (95 RON) is also acceptable for
all models. Do not use leaded gasoline.

USING REFORMULATED (OXYGENATED) GASOLINE (USA ONLY)

Reformulated gasoline is required in certain areas of the USA and is
acceptable for use in your Mercury Marine engine. The only oxygenate
currently in use in the USA is alcohol (ethanol, methanol, or butanol).

GASOLINE CONTAINING ALCOHOL

Bu16 Butanol Fuel Blends

Fuel blends of up to 16.1% butanol (Bu16) that meet the published Mercury
Marine fuel rating requirements are an acceptable substitute for unleaded
gasoline. Contact your boat manufacturer for specific recommendations on
your boat's fuel system components (fuel tanks, fuel lines, and fittings).

Methanol and Ethanol Fuel Blends

IMPORTANT: The fuel system components on your Mercury Marine engine will
withstand up to 10% alcohol (methanol or ethanol) content in the gasoline. Your
boat's fuel system may not be capable of withstanding the same percentage of
alcohol. Contact your boat manufacturer for specific recommendations on your
boat's fuel system components (fuel tanks, fuel lines, and fittings).

Be aware that gasoline containing methanol or ethanol may cause increased:

• Corrosion of metal parts

• Deterioration of rubber or plastic parts

• Fuel permeation through the rubber fuel lines

• Likelihood of phase separation (water and alcohol separating from the
gasoline in the fuel tank)

FUEL AND OIL

eng 29

!

WARNING

Fuel leakage is a fire or explosion hazard, which can cause serious injury or
death. Periodically inspect all fuel system components for leaks, softening,
hardening, swelling, or corrosion, particularly after storage. Any sign of
leakage or deterioration requires replacement before further engine
operation.

IMPORTANT: If you use gasoline that contains or might contain methanol or
ethanol, you must increase the frequency of inspection for leaks and
abnormalities.

IMPORTANT: When operating a Mercury Marine engine on gasoline containing
methanol or ethanol, do not store the gasoline in the fuel tank for long periods.
Cars normally consume these blended fuels before they can absorb enough
moisture to cause trouble; boats often sit idle long enough for phase separation
to take place. Internal corrosion may occur during storage if alcohol has
washed protective oil films from internal components.

Oil Recommendation

Recommended Oil

Mercury or Quicksilver Premium 2‑Cycle TC‑W3
Outboard Oil

IMPORTANT: Oil must be NMMA certified TC‑W3 2‑Cycle oil.
Mercury or Quicksilver Premium TC‑W3 2‑Cycle oil is recommended for this

engine. For added protection and lubrication, Mercury or Quicksilver Premium
Plus TC‑W3 2‑Cycle oil is recommended. If Mercury or Quicksilver outboard oil
is not available, substitute another brand of 2‑cycle outboard oil that is NMMA
Certified TC‑W3. Severe engine damage may result from use of an inferior oil.

Mixing Fuel and Oil

Use a 1:25 oil/gasoline mixture in the first tank of fuel.
After the break‑in fuel mixture is used up, use a 1:50 oil/gasoline mixture. Refer

to the table (following) for mixing ratios.

OIL/GASOLINE MIXING RATIO CHART

GASOLINE/OIL MIXING RATIO CHART

Oil/Gas Ratio

3.8 liters

(1 US gal) gas

11.5 liters

(3 US gal) gas

23 liters

(6 US gal) gas

1:25

148 ml (5 fl oz) oil

473 ml (16 fl oz)

oil

946 ml (32 fl oz)

oil

1:50

89 ml (3 fl oz) oil 237 ml (8 fl oz) oil

473 ml (16 fl oz)

oil

FUEL AND OIL

30 eng

MIXING PROCEDURE

Pour the full amount of oil, along with one gallon of gasoline, into an approved
container. Shake the two together until they are thoroughly mixed. Add the
remainder of gasoline and shake container to ensure mixing.

Engine Break‑In

ENGINE BREAK-IN FUEL MIXTURE

Use a 1:25 oil/gasoline mixture in the first tank of fuel.

ENGINE BREAK-IN PROCEDURE

Refer to Operation ‑ Engine Break‑In Procedure for correct break‑in
procedure.

Filling Fuel Tank

!

WARNING

Avoid serious injury or death from a gasoline fire or explosion. Use caution
when filling fuel tanks. Always stop the engine and do not smoke or allow
open flames or sparks in the area while filling fuel tanks.

Fill fuel tanks outdoors away from heat, sparks, and open flames.
Always stop engine before refilling tanks.
Do not completely fill the fuel tanks. Leave approximately 10% of the tank

volume unfilled. Fuel will expand in volume as its temperature rises and can
leak under pressure if the tank is completely filled.

FILLING FUEL TANKS PERMANENTLY INSTALLED

Slowly pour the correct amount of oil along with gasoline as the tank is being
filled.

FILLING PORTABLE FUEL TANKS

Remove the portable fuel tanks from the boat to refill them.
Pour the full amount of oil, along with one gallon of gasoline, into the fuel tank.

Mix thoroughly, then pour the remainder of gasoline into the tank.

PORTABLE FUEL TANK PLACEMENT IN THE BOAT

Place the fuel tank in the boat so the vent is higher than the fuel level under
normal boat operating conditions.

FUEL AND OIL

eng 31

Remote Control Features

Your boat may be equipped with the remote control shown. If not, consult your
dealer for a description of the functions and operations of the remote control.

a - Remote control handle
b - Throttle only lever
c - Ignition key switch
d - Lanyard stop switch

Tilt Up and Tilt Down

BASIC TILTING OPERATION

The tilt feature allows the operator to tilt the outboard to a higher tilt angle for
operation in shallow water, or tilt the outboard to the full up position.

When running the outboard, keep the tilt lever in the release position. This
allows the outboard to return to the running position if the outboard should hit
an underwater obstacle and be lifted up.

Moving the tilt lever to the tilt position will allow the outboard to lock into the
shallow water drive position or the full up position.

IMPORTANT: When tilting up or down, be careful not to place your hand
between the swivel bracket and the stern bracket. Be sure to tilt the outboard
down slowly.

NOTE: Stop the engine before tilting up.

1. Stop the engine.

37982

a

b

c

d

FEATURES AND CONTROLS

32 eng

2. With the shift lever in Neutral (N) or Forward (F), fully tilt the motor up
toward by holding the tilt handle provided at the rear of the upper motor
cover.

27023

3.

Tilt up: Push the reverse lock lever down until it stops. This is the tilt up
position.

4. Tilt the engine all the way up until it locks in place.

a - Reverse lock lever

5.

Tilt down: Pull the reverse lock lever upward until it stops. This is the tilt
down position.

6. Lift the engine up slightly, and then allow gravity to lower it for you.

a - Tilt down position
b - Tilt up position
c - Reverse lock lever

37535

a

39484

a

b

c

FEATURES AND CONTROLS

eng 33

Shallow Water Operation

IMPORTANT: When in shallow water operation, be careful not to place your
hand between the swivel bracket and the stern bracket. Be sure to tilt the
outboard down slowly.

NOTE: Slow down to trolling speed, and shift to Neutral (N) before operating in
shallow water.

1. Stop the engine.

2.

Tilt up: Put the reverse lock lever in the tilt up position, and tilt up the
engine to put the engine in the shallow water running position.

a - Reverse lock lever

3.

Tilt down: Pull the reverse lock lever in the tilt down position, slightly lift
up the engine, then put it down.

a - Tilt down position
b - Tilt up position
c - Reverse lock lever

37535

a

39484

a

b

c

FEATURES AND CONTROLS

34 eng

NOTE: Please follow the instructions below:

• Ensure that the water inlet is submerged at all times and that water is
continuously running out of the cooling water check port.

• Be sure to run the engine slowly when using the shallow water drive.
Running at higher speed will result in lack of control and may damage the
engine.

• Ensure the motor does not strike the bottom, especially when running in
reverse. If the motor does strike the bottom while in reverse, the impact is
transmitted to the transom, which could damage both the motor and the
boat.

Trim Angle Adjustment

The vertical operating angle of your outboard is adjusted by changing the
position of the tilt pin in the adjustment holes provided. Proper adjustment
allows the boat to achieve optimum performance, stability, and minimize
steering effort.

The following instructions explain how to set the best angle of the boat.
The tilt pin should be adjusted so the outboard is positioned to run

perpendicular to the water when the boat is running at full speed. This allows
the boat to be driven parallel to the water.

Arrange passengers and load in the boat so the weight is distributed evenly.
The trim angle is adjusted by setting the trim position pin in the correct trim

position.

TRIM POSITION ADJUSTMENTS

•

Correct trim: The trim angle is optimum when the boat is parallel to the
water surface while running.

•

Trim down: If the trim angle is excessive, the bow will rise out of the
water and the speed will decrease. Furthermore, the bow may sway or the
bottom may slam the water while cruising. In this case, decrease the trim
angle by setting the trim position pin in a lower position.

FEATURES AND CONTROLS

eng 35

•

Trim up: If the trim angle is too small, the bow will enter the water, the
speed will decrease, and water may enter the boat. In this case, the trim
angle should be increased by setting the trim position pin in a higher
position.

a - Correct trim
b - Trim down
c - Trim up
d - Move pin to raise bow up
e - Move pin to lower bow down
f - Trim position pin

Steering Friction Adjustment

Steering friction can be adjusted according to your preference with the steering
co‑pilot.

!

WARNING

Insufficient friction adjustment can cause serious injury or death due to loss
of boat control. When setting the friction adjustment, maintain sufficient
steering friction to prevent the outboard from steering into a full turn if the
tiller handle or steering wheel is released.

Adjust the steering co‑pilot to achieve desired steering friction.

• Turn clockwise for more friction.

41064

f

b

c

a

d

e

FEATURES AND CONTROLS

36 eng

• Turn counterclockwise for less friction.

a - Steering co‑pilot

NOTE: The steering adjustment bolt is used to adjust the sliding friction of the
steering, but not to correct the steering. If excess tightening is given to the bolt,
it may cause damage to the swivel bracket.

Throttle Grip Turning Friction Adjustment

Turn the friction adjustment screw to set and maintain the throttle at desired
speed. Turn screw clockwise to tighten friction and turn screw counterclockwise
to loosen friction.

a - Tighten friction
b - Loosen friction
c - Throttle adjustment screw

Trim Tab Adjustment

Propeller steering torque will cause the boat to pull in one direction. This
steering torque is a normal result from the outboard not trimmed with the
propeller shaft parallel to the water surface. The trim tab can help compensate
for this steering torque in many cases and can be adjusted within limits to
reduce any unequal steering effort.

• Operate the boat at normal cruising speed with the outboard set at the
desired operating angle position. Turn the boat left and right and note the
direction the boat turns more easily.

40867

a

41034

c

b

a

FEATURES AND CONTROLS

eng 37

• If adjustment is necessary, loosen the trim tab bolt and make small
adjustments at a time.

• After the adjustment, securely tighten the trim tab bolt.

NOTE: Check for looseness of the bolt and the trim tab at regular intervals. Due
to corrosion, the trim tab will wear down over time.

The trim tab is located under the anti‑ventilation plate.

• If the boat steers toward the left, set the trim tab in the direction of B.

• If the boat steers toward the right, set the trim tab in the direction of C.

a - Trim tab
b - Steers toward the left, set the trim tab in the direction of B
c - Steers toward the right, set the trim tab in the direction of C
d - Turning left
e - Turning right

IMPORTANT: The trim tab also acts as an anode to prevent galvanic corrosion.
Do not apply any paint, grease, or other material to the surface of the trim tab.

NOTE: Trim tab adjustment will have little effect reducing steering torque if the
outboard is installed with the anti‑ventilation plate approximately 50 mm (2 in.)
or more above the boat bottom.

37494

a

b

c

d

e

FEATURES AND CONTROLS

38 eng

REMOTE CONTROL LEVER FRICTION (THROTTLE FRICTION
ADJUSTMENT SCREW)

To adjust the friction of the remote control lever, turn the throttle friction
adjustment screw on the front of the remote control box. Turn clockwise to
increase the friction and counterclockwise to decrease it.

a - Turn counterclockwise to

decrease the friction

b - Turn clockwise to increase the

friction

c - Throttle friction adjustment

screw

38385

a

b

c

FEATURES AND CONTROLS

eng 39

Prestarting Check List

• Operator knows safe navigation, boating, and operating procedures.

• An approved personal flotation device of suitable size for each person
aboard and readily accessible (it is the law).

• A ring type life buoy or buoyant cushion designed to be thrown to a
person in the water.

• Know your boats' maximum load capacity. Look at the boat capacity plate.

• Fuel supply OK.

• Arrange passengers and load in the boat so the weight is distributed
evenly and everyone is seated in a proper seat.

• Tell someone where you are going and when you expect to return.

• It is illegal to operate a boat while under the influence of alcohol or drugs.

• Know the waters and area you will be boating; tides, currents, sand bars,
rocks, and other hazards.

•

Make inspection checks listed in Maintenance ‑ Inspection and

Maintenance Schedule.

Operating in Freezing Temperatures

When using your outboard or having your outboard moored in freezing or near
freezing temperatures, keep the outboard tilted down at all times so the
gearcase is submerged. This prevents the trapped water in the gearcase from
freezing and causing possible damage to the water pump and other
components.

If there is a chance of ice forming on the water, the outboard should be
removed and drained completely of water. If ice should form at the water level
inside the outboard driveshaft housing, it will block water flow to the engine
causing possible damage.

Operating in Saltwater or Polluted Water

We recommend that you flush the internal water passages of your outboard
with fresh water after each use in salt or polluted water. This will prevent a
buildup of deposits from clogging the water passages. Refer to Maintenance ‑
Flushing the Cooling System.

If you keep your boat moored in the water, always tilt the outboard so the
gearcase is completely out of water (except in freezing temperatures) when not
in use.

Wash the outboard exterior and flush out the exhaust outlet of the propeller and
gearcase with fresh water after each use. Each month, spray Mercury Precision
or Quicksilver Corrosion Guard on external metal surfaces. Do not spray on
corrosion control anodes as this will reduce the effectiveness of the anodes.

OPERATION

40 eng

Operating at High Elevations

IMPORTANT: To prevent serious damage to the engine caused by a lean fuel
mixture, do not operate your outboard (if the jets were changed for high
elevation) at a lower elevation unless the jets are changed again to correspond
to the new elevation.

Operating your outboard at an elevation higher than 750 m (2500 ft) above sea
level may require a carburetor jet change and/or different pitch propeller.
Consult your dealer. This will reduce the normal performance loss experienced
as a result of reduced oxygen in the air causing an overly rich fuel mixture.

Operating Outboard as an Auxiliary Engine

If the outboard is used as an auxiliary engine, stop the engine and tilt the
outboard out of the water when using the main power source.

IMPORTANT: The outboard must be restrained from bouncing while operating
the boat using the main power source. Bouncing can damage the outboard and
boat transom.

Prestarting Instructions

1. Attach the fuel connector to the engine connector. The arrow‑mark on the
primer bulb should be facing the engine.

41508

NOTICE

Without sufficient cooling water, the engine, the water pump, and other
components will overheat and suffer damage. Provide a sufficient supply of
water to the water inlets during operation.

OPERATION

eng 41

2. Loosen the air vent screw on the tank cap.

37518

3. Feed fuel to the carburetor by squeezing the primer bulb until it is firm.

a - To fuel tank
b - To engine
c - Fuel flow direction

4. Make sure the cooling water intake is submerged.

43116

Engine Break‑In Procedure

IMPORTANT: Failure to follow the engine break‑in procedures can result in
poor performance throughout the life of the engine and can cause engine
damage. Always follow break‑in procedures.

ENGINE OIL

Use Mercury or Quicksilver engine oil or the other recommended oil (TC‑W3).

37714

a

c

b

OPERATION

42 eng

NOTE: Do not mix different brands of oil. The mixing of different brands, or
different kinds even if the same brand, may cause gelling, resulting in blockage
of filter screens. This may lead to serious engine damage due to the lack of
lubrication.

Mixing ratio (1:50): Mercury or Quicksilver engine oil or recommended engine
oil (TC‑W3), 1:Unleaded gasoline 50.

ENGINE BREAK-IN FUEL MIXTURE

Use a 1:25 oil/gasoline mixture in the first tank of fuel. Use Mercury or
Quicksilver engine oil or the recommended oil (TC‑W3).

BREAK-IN

Break‑in period for 10 hours

Vary the throttle setting during the first hour of operation.
During the first hour of operation, avoid remaining at a constant speed for more

than two minutes and avoid sustained wide‑open throttle.

Time 0–9 min.

10–59

min.

1:00–1:59

hrs.

2:00–9:59

hrs.

10 hrs.

Method of
operation

Idling or
trolling

Throttle
open
less than
½ of the
way
(about
3000
RPM)

Throttle open
less than 3/4
of the way
(about 4000
RPM)

Throttle open
3/4 of the
way (about
4000 RPM)

Normal
operating

Conditions

Cruising at
no more
than
minimum
speed

A full‑throttle
run is allowed
for 1 min.
every 10 min.

A full‑throttle
run is
allowed for 2
min. every 10
min.

Warming Up the Engine

Warm the engine at low engine speeds for about three minutes. This allows the
lubrication oil to circulate to all parts of the engine. Operating the engine
without allowing it to warm up, shortens the engine life. Be sure to check that
water is coming out of the water pump indicator when warming up the engine.

OPERATION

eng 43

NOTE: If the engine is operated continuously without water discharging from
the water pump indicator or idle hole, the engine may overheat.

a - Water pump indicator
b - Idle hole

Engine speeds: Idling speed after warming up.

In gear

In Neutral

800 RPM 950 RPM

Starting the Engine

Before starting, read the Prestarting Check List, special operating
instructions, and Engine Break‑in Procedure in the Operation section.

Electric starting outboard models must not be started manually using the
starter rope, or run, without having the battery leads connected to a
battery. Damage to the charging system could result.

IMPORTANT: If no water is coming out of the water pump indicator hole, stop
engine and check cooling water intake for obstruction. No obstruction may
indicate a water pump failure or blockage in the cooling system. These
conditions will cause the engine to overheat. Have the outboard checked by
your dealer. Operating the engine while overheated will cause serious engine
damage.

1.

MH and EH Models: Place the shift lever in the Neutral (N) position.

38347

NOTE: Be sure that the shift lever is in Neutral (N) when starting the engine.
This model is provided with a function that prevents starting in gear.

40472

a

b

OPERATION

44 eng

IMPORTANT: If the motor somehow does start in gear, do not use it. Contact
your authorized dealer.

2. Turn the throttle grip until the mark on the grip faces the triangular mark
on the steering handle.

28847

3. Pull the choke knob out all the way. The choke operation is not necessary
when the engine is warm.

38349

4.

MH models: Pull the starter handle slowly until you feel resistance. Then
pull it quickly.

a - Pull slowly
b - Pull quickly

37523

a

b

OPERATION

eng 45

5.

EH Models: Push the starter switch button.

a - Starter switch button

6. Release the button when the engine has started.

IMPORTANT: If the choke knob was used for the engine start, push it back
when the engine has started.

7.

E Models: Insert the main switch key.

8. Set the control lever in the Neutral (N) position. Raise the Neutral (N)
warm‑up lever.

a - Fully opened
b - Fully closed
c - Neutral warm‑up lever
d - Ignition key
e - Lanyard stop switch

9. Turn the main switch key to the start position. Then, continuously push
the key to operate the choke.

39481

a

37715

N

c

d

e

a

b

OPERATION

46 eng

NOTE: Choke operation is not necessary if the engine is warm.

a - Off
b - On
c - Push to operate choke

10. Stop pushing the key when the engine has started. The key returns to the
original position automatically.

NOTE: The neutral warm‑up lever cannot be raised when the control lever
shift is in Forward (F) or Reverse (R).

NOTE:

E and EH Models:

• Continuous operation of the starter motor can shorten the life of the
battery and the starter motor. Operate the starter motor for a maximum of
three seconds. If the engine does not start, wait five seconds before
engaging the starter motor again.

• Do not engage the starter motor after the engine has started.

Gear Shifting

IMPORTANT: Observe the following:

•

Never shift the outboard into gear unless the engine speed is at idle.
Do not shift the outboard into reverse when the engine is not
running.

MH and EH Models

1.

Forward: Turn the throttle grip to reduce the engine speed. When the
engine reaches trolling speed, quickly pull the shift lever to the Forward
(F) position.

37466

a

b

c

OPERATION

eng 47

2.

Reverse: As when shifting to Forward (F), reduce the engine speed,
when the engine reaches trolling speed, quickly push the shift lever to
Reverse (R) position.

a - Reverse (R)
b - Forward (F)

E Models

1.

Forward: Quickly push the control lever to the Forward (F) position at
32°, where the gear is connected, while lifting up on the lock button
located at the bottom of the control lever grip. Further shifting will open
the throttle.

2.

Reverse: Quickly pull the control lever to the Reverse (R) position at 32°,
where the gear is connected, while lifting up on the lock button located at
the bottom of the control lever grip. Further shifting will open the throttle.

NOTE: The control lever is inoperative unless the neutral warm‑up lever is in
the fully closed position.

37713

a

b

OPERATION

48 eng

NOTE: Do not increase the engine speed unnecessarily when operating the
neutral warm‑up lever.

a - Fully open
b - Throttle
c - Forward (F)
d - Shift
e - Neutral (N)
f - Reverse (R)
g - Fully closed
h - Neutral warm‑up lever
i - Lock button

Stopping the Engine

MH and EH Models

1. Turn the throttle grip to the low speed position.

2. Put the shift lever into the Neutral (N) position. Run the engine for 2–3
minutes at idling speed if it has been running at full speed.

39483

a

b

g

d

d

g

f

c

a

h

i

e

OPERATION

eng 49

3. Push the stop switch to stop the engine.

37877

E Models

1. Put the shift lever into the Neutral (N) position and run the engine for 2–3
minutes at idling speed.

37882

N

OPERATION

50 eng

2. Turn the main switch key to the off position or pull out the lanyard stop
switch lock.

a - Hook
b - Off
c - On
d - Lanyard stop switch

lock

IMPORTANT: Please follow the instructions below:

• After stopping the engine, close the air vent screw on the tank cap.

• Disconnect the fuel connector of the engine or the fuel tank.

• Disconnect the battery cable of the EH or E type engine, if the engine will
not be used for more than three days.

Emergency Starting

If the starter system fails, use the spare starter rope provided and follow the
procedure.

Remove the top cowl and use the spare starter rope provided and follow the
procedure.

1. Pull directly on the starter rope by hand.

2. Use a 10 mm socket wrench as a handle on the rope.

38361

37716

a

b

c

d

OPERATION

eng 51

!

WARNING

High voltage is present any time the key is turned on, especially when
starting or operating the engine. Do not touch ignition components or metal
test probes and stay clear of spark plug leads when performing live tests.

!

WARNING

The exposed moving flywheel can cause serious injury. Keep your hands,
hair, clothing, tools, and other objects away from engine when starting or
running the engine. Do not attempt to reinstall the flywheel cover or top
cowl when engine is running.

OPERATION

52 eng

Cleaning Care Recommendations

OUTBOARD CARE

To keep your outboard in the best operating condition, it is important that your
outboard receive the periodic inspections and maintenance listed in the
Inspection and Maintenance Schedule. We urge you to keep it maintained
properly to ensure the safety of you and your passengers, and retain its
dependability.

Record maintenance performed in the Maintenance Log at the back of this
book. Save all maintenance work orders and receipts.

Selecting Replacement Parts For Your Outboard

We recommend using original Mercury Precision or Quicksilver replacement
parts and Genuine Lubricants.

DO NOT USE CAUSTIC CLEANING CHEMICALS

IMPORTANT: Do not use caustic cleaning chemicals on the outboard power
package. Some cleaning products contain strong caustic agents such as hull
cleaners with hydrochloric acid. These cleaners can degrade some of the
components they come in contact with including critical steering fasteners.

Damage to steering fasteners may not be obvious during visual inspection and
this damage may lead to catastrophic failure. Some caustic cleaning chemicals
may cause or accelerate corrosion. Exercise caution when using cleaning
chemicals around the engine and follow the recommendations on the
packaging of the cleaning product.

CLEANING GAUGES

IMPORTANT: Never use high‑pressure water to clean gauges.
Routine cleaning of the gauges is recommended to prevent a buildup of salt

and other environmental debris. Crystalized salt can scratch the gauge display
lens when using a dry or damp cloth. Ensure that the cloth has a sufficient
amount of fresh water to dissolve and remove salt or mineral deposits. Do not
apply aggressive pressure on the display lens while cleaning.

When water marks cannot be removed with a damp cloth, mix a 50/50 solution
of warm water and isopropyl alcohol to clean the display lens. Do not use
acetone, mineral spirits, turpentine type solvents, or ammonia based cleaning
products. The use of strong solvents or detergents may damage the coating,
the plastics, or the rubber keys on the gauges. If the gauge has a sun cover
available, it is recommended that the cover be installed when the unit is not in
use to prevent UV damage to the plastic bezels and rubber keys.

CLEANING REMOTE CONTROLS

IMPORTANT: Never use high‑pressure water to clean remote controls.

MAINTENANCE

eng 53

Routine cleaning of the remote control external surfaces is recommended to
prevent a buildup of salt and other environmental debris. Use a cloth towel
which has a sufficient amount of fresh water to dissolve and remove salt or
mineral deposits.

When water marks cannot be removed with a damp cloth, mix a 50/50 solution
of warm water and isopropyl alcohol to clean the remote control. Do not use
acetone, mineral spirits, turpentine type solvents, or ammonia based cleaning
products. The use of strong solvents or detergents may damage the coating,
the plastics, or the rubber components on the remote control.

CLEANING CARE FOR TOP AND BOTTOM COWLS

IMPORTANT: Dry wiping (wiping the plastic surface when it is dry) will result in
minor surface scratches. Always wet the surface before cleaning. Do not use
detergents containing hydrochloric acid. Follow the cleaning and waxing
procedure.

Cleaning and Waxing Procedure

1. Before washing, rinse the cowls with clean water to remove dirt and dust
that may scratch the surface.

2. Wash the cowls with clean water and a mild nonabrasive soap. Use a soft
clean cloth when washing.

3. Dry thoroughly with a soft clean cloth.

4. Wax the surface using a nonabrasive automotive polish (polish designed
for clear coat finishes). Remove the applied wax by hand using a clean
soft cloth.

5. To remove minor scratches, use Mercury Marine Cowl Finishing
Compound (92‑859026K 1).

Outboard Care

To keep your outboard in the best operating condition, it is important that your
outboard receive the periodic inspections and maintenance listed in the
Inspection and Maintenance Schedule. We urge you to keep it maintained
properly to ensure the safety of you and your passengers, and retain its
dependability.

Record maintenance performed in the Maintenance Log at the back of this
book. Save all maintenance work orders and receipts.

SELECTING REPLACEMENT PARTS FOR YOUR OUTBOARD

We recommend using original Mercury Precision or Quicksilver replacement
parts and Genuine Lubricants.

Inspection and Maintenance Schedule

DAILY CHECKS

• Check the engine oil level

• Check the lanyard stop switch

MAINTENANCE

54 eng

• Inspect the fuel system for leaks

• Inspect the engine tightness on the transom

• Check the steering system for binding

• Check the propeller for damage

• Inspect the hydraulic steering fittings and hoses for leaks or signs of
damage, if equipped

• Check the hydraulic steering fluid level, if equipped

AFTER EACH USE

• Wash the power package exterior with fresh water

• Flush the outboard cooling system, saltwater or brackish water only

ANNUALLY OR 100 HOURS

• Grease the engine, if applicable

• Change the engine oil and filter, if equipped

• Inspect the thermostat, saltwater or brackish water only

• Add Quickleen to the fuel tank, once per year, per engine

• Apply antiseize to the spark plug threads

• Replace the gear lubricant

• Inspect the corrosion control anodes

• Lubricate the propeller shaft splines

• Replace all filters on the suction side of the fuel system—dealer item

• Lubricate the driveshaft splines—dealer item

• Check the tightness on all the fasteners—dealer item

• Check the torque of the outboard mounting hardware—dealer item

• Check the battery condition and tightness of the battery cable connection,
if equipped—dealer item

THREE YEARS OR 300 HOURS

• Replace the spark plugs

• Replace the water pump impeller—dealer item

• Inspect the carbon fiber reeds, if equipped—dealer item

• Inspect the wire harness connectors—dealer item

• Check the remote control cable adjustment, if equipped—dealer item

• Replace the high‑pressure fuel filter, if equipped—dealer item

• Replace the accessory drive belt, if equipped—dealer item

• Check the power trim fluid level, if equipped—dealer item

• Inspect the engine motor mounts—dealer item

MAINTENANCE

eng 55

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.

!

WARNING

Rotating propellers can cause serious injury or death. Never operate the boat
out of the water with a propeller installed. Before installing or removing a
propeller, place the drive unit in neutral and engage the lanyard stop switch
to prevent the engine from starting. Place a block of wood between the
propeller blade and the anti‑ventilation plate.

1.

Remove the propeller. Refer to Propeller Replacement. Install the
flushing attachment so the rubber cups fit tightly over the cooling water
intake.

27256

Flushing Device 91‑44357Q 2

9192

Attaches to the water intakes; provides
a fresh water connection when flushing
the cooling system or operating the
engine.

MAINTENANCE

56 eng

2. Attach a water hose to the flushing attachment. Turn on the water and
adjust the flow so water is leaking around the rubber cups to ensure the
engine receives an adequate supply of cooling water.

27259

3. Start the engine and run it at idle speed in neutral shift position.

IMPORTANT: Do not run the engine above idle when flushing.

4. Adjust the water flow (if necessary) so excess water continues leaking out
from around the rubber cups to ensure the engine is receiving an
adequate supply of cooling water.

27260

5. Check for a steady stream of water flowing out of the water pump
indicator hole. Continue flushing the outboard for 3 to 5 minutes, carefully
monitoring water supply at all times.

6. Stop the engine, turn off the water, and remove the flushing attachment.
Install the propeller.

Top Cowl Removal and Installation

REMOVAL

1. Unlock the rear latch by pushing lever down.

29054

MAINTENANCE

eng 57

2. Lift rear of cowl and disengage front hook.

26851

INSTALLATION

1. Engage the front hook and push cowl back over the cowl seal.

2. Push cowl down and move the rear latch lever up to lock.

Battery Inspection

The battery should be inspected at periodic intervals to ensure proper engine
starting capability.

IMPORTANT: Read the safety and maintenance instructions which accompany
your battery.

1. Turn off the engine before servicing the battery.

2. Ensure the battery is secure against movement.

3. Battery cable terminals should be clean, tight, and correctly installed.
Positive to positive and negative to negative.

4. Ensure the battery is equipped with a nonconductive shield to prevent
accidental shorting of battery terminals.

Fuel System

!

WARNING

Fuel is flammable and explosive. Ensure that the key switch is off and the
lanyard is positioned so that the engine cannot start. Do not smoke or allow
sources of spark or open flame in the area while servicing. Keep the work
area well ventilated and avoid prolonged exposure to vapors. Always check
for leaks before attempting to start the engine, and wipe up any spilled fuel
immediately.

Before servicing any part of the fuel system, stop the engine and disconnect
the battery. Drain the fuel system completely. Use an approved container to
collect and store fuel. Wipe up any spillage immediately. Material used to
contain spillage must be disposed of in an approved receptacle. Any fuel
system service must be performed in a well‑ventilated area. Inspect any
completed service work for sign of fuel leakage.

MAINTENANCE

58 eng

FUEL LINE INSPECTION

Visually inspect the fuel line and primer bulb for cracks, swelling, leaks,
hardness, or other signs of deterioration or damage. If any of these conditions
are found, the fuel line or primer bulb must be replaced.

ENGINE FUEL FILTER

Inspect the sight bowl for water accumulation and inspect the filter element for
sediment. Clean the filter as follows.

Cleaning the fuel filters and the fuel tank

Fuel filters are provided inside the fuel tank and engine.

1.

Fuel tank filter: Loosen the fuel pickup elbow shown, remove it and clean
the fuel filter.

a - Filter
b - Fuel pickup elbow

37711

b

a

MAINTENANCE

eng 59

2.

Engine filter: Remove cap, then clean the fuel filter in the engine.

a - Carburetor
b - Fuel filter

3.

Fuel tank: Water or dirt in the fuel tank may cause engine trouble. Clean
the tank at specified times or after the motor has been stored for a long
period (over three months).

IMPORTANT: Visually inspect for fuel leakage from the filter by squeezing the
primer bulb until firm, forcing fuel into the filter.

Exterior Care

Your outboard is protected with a durable baked enamel finish. Clean and wax
often using marine cleaners and waxes.

Fuse Replacement ‑ Electric Start Remote Control Models

IMPORTANT: Always carry spare SFE 20 amp fuses.

40475

a

b

MAINTENANCE

60 eng

The electric starting circuit is protected from overload by an SFE 20 amp fuse.
If the fuse is blown, the electric starter motor will not operate. Try to locate and
correct the cause of the overload. If the cause is not found, the fuse may blow
again. Replace fuse with a fuse of the same rating.

3036

Replacing the Anodes

The outboard has a corrosion control anode installed on the gearcase. An
anode helps protect the outboard against galvanic corrosion by sacrificing its
metal to be slowly eroded instead of the outboard metals.

Two anodes are fitted at the gearcase and the mount bracket. When the
anodes has been eroded more than 2/3, replace it immediately.

a - Anode/trim tab

IMPORTANT: Please follow the instructions below:

1. Never grease or paint the anode.

2. At each inspection, retighten the anode attaching bolt, as it is likely to be
subjected to electrolytic corrosion.

37879

a

MAINTENANCE

eng 61

Propeller Replacement

!

WARNING

Rotating propellers can cause serious injury or death. Never operate the boat
out of the water with a propeller installed. Before installing or removing a
propeller, place the drive unit in neutral and engage the lanyard stop switch
to prevent the engine from starting. Place a block of wood between the
propeller blade and the anti‑ventilation plate.

1. Shift outboard to Neutral (N) position.

38347

2. Remove the spark plug leads to prevent the engine from starting.

26899

3. Place a block of wood between the gearcase and the propeller to hold the
propeller and remove the propeller nut.

27296

MAINTENANCE

62 eng

4. Remove the propeller from the shaft. If the propeller is seized to the shaft
and cannot be removed, have the propeller removed by an authorized
dealer.

a - Cotter pin
b - Nut
c - Washer
d - Propeller
e - Thrust hub

5. Coat the propeller shaft with Mercury Extreme Grease or 2‑4‑C with
PTFE.

27305

Tube Ref

No.

Description Where Used Part No.

Extreme Grease Propeller shaft 8M0071842

95

2-4-C with PTFE Propeller shaft 92-802859A 1

IMPORTANT: To prevent the propeller hub from corroding and seizing to the
propeller shaft (especially in saltwater), always apply a coat of the
recommended lubricant to the entire propeller shaft at the recommended
maintenance intervals, and also each time the propeller is removed.

38055

a

c

d

e

b

MAINTENANCE

eng 63

6. Install forward thrust hub, propeller, washer, nut, and cotter pin onto the
propeller shaft.

a - Cotter pin
b - Nut
c - Washer
d - Propeller
e - Forward thrust hub
f - Propeller shaft

7. Place a block of wood between the gearcase and propeller and tighten
the propeller nut.

27341

8. Install the spark plug leads.

37520

a

b

c

d

e

f

MAINTENANCE

64 eng

Spark Plug Inspection and Replacement

!

WARNING

Damaged spark plug boots may emit sparks that can ignite fuel vapors under
the engine cowl, resulting in serious injury or death from a fire or explosion.
To avoid damaging the spark plug boots, do not use any sharp object or
metal tool to remove the spark plug boots.

1. Remove the spark plug leads. Twist the rubber boots slightly and pull off.

26899

2. Remove the spark plugs to inspect. Replace the spark plug if the
electrode is worn or the insulator is rough, cracked, broken, blistered, or
fouled.

26946

3. Set the spark plug gap (0.9–1.0 mm).

26947

Spark Plug
NGK B7HS‑10 or BPR7HS‑10 or recommended ones (Champion L82 or RL

82C with 1.0 mm gap)

4. Before installing spark plugs, clean off any dirt on the spark plug seats.
Install plugs finger‑tight, then tighten 1/4 turn or torque to specifications.

MAINTENANCE

eng 65

Description Nm lb‑in. lb‑ft
Spark plug 27 – 20

Lubrication Points

Only let an authorized Mercury dealer perform service or maintenance on this
product. Be sure to use genuine parts, genuine lubricants, or recommended
lubricants.

Changing Gear Oil

1. Place the outboard in a vertical operating position.

2. Place a drain pan below the outboard.

3. Remove the oil plugs (upper and lower) and drain the gear oil completely.

a - Upper oil drain plug
b - Lower oil drain plug
c - Water strainer

4. Insert the oil tube nozzle into the lower oil drain plug hole and fill with gear
oil by squeezing the oil tube until oil flows out of the upper plug hole.

a - Upper oil drain plug
b - Lower oil drain plug
c - Water strainer

5. Install the upper oil drain plug, then remove the oil tube nozzle and install
the lower oil drain plug.

40473

b

a

c

40474

b

a

c

MAINTENANCE

66 eng

IMPORTANT: Use Mercury/Quicksilver gear oil or the recommended one (APL
GL‑5: SAE #80–#90). Required volume: 370 ml (0.10 US gal).

Submerged Outboard

A submerged outboard will require service within a few hours by an authorized
dealer once the outboard is recovered from the water. This immediate attention
by a servicing dealer is necessary once the engine is exposed to the
atmosphere to minimize internal corrosion damage to the engine.

MAINTENANCE

eng 67

Preseason Check

1. Check the electrolyte level, and measure the voltage and specific gravity
of the battery.

Specific Gravity at 20 °C Terminal Voltage (V) Charge Condition

1.120 10.5 Fully discharged

1.160 11.1 1/4 charged

1.210 11.7 1/2 charged

1.250 12.0 3/4 charged

1.280 13.2 Fully charged

2. Check that the battery is secure and the battery cables are properly
installed.

3. Check that the shift and throttle function properly. Be sure to turn the
propeller shaft when checking the shift function or else the shift linkage
may be damaged.

Storage Preparation

The major consideration in preparing your outboard for storage is to protect it
from rust, corrosion, and damage caused by freezing of trapped water.

The following storage procedures should be followed to prepare your outboard
for out of season storage or prolonged storage (two months or longer).

NOTICE

Without sufficient cooling water, the engine, the water pump, and other
components will overheat and suffer damage. Provide a sufficient supply of
water to the water inlets during operation.

FUEL SYSTEM

IMPORTANT: Gasoline containing alcohol (ethanol or methanol) can cause a
formation of acid during storage and can damage the fuel system. If the
gasoline being used contains alcohol, it is advisable to drain as much of the
remaining gasoline as possible from the fuel tank, remote fuel line, and engine
fuel system.

Fill the fuel tank and engine fuel system with treated (stabilized) fuel to help
prevent formation of varnish and gum. Proceed with the following instructions.

• Portable fuel tank ‑ Pour the required amount of gasoline stabilizer (follow
instructions on container) into the fuel tank. Tip fuel tank back and forth to
mix stabilizer with the fuel.

• Permanently installed fuel tank ‑ Pour the required amount of gasoline
stabilizer (follow instructions on container) into a separate container and
mix with approximately 1 liter (1 U.S. qt) of gasoline. Pour this mixture into
the fuel tank.

STORAGE

68 eng

• Place the outboard in water or connect flushing attachment for circulating
cooling water. Run the engine at idle RPM for ten minutes to fill the
engine fuel system with stabilized fuel.

Protecting External Outboard Components

•

Lubricate all outboard components listed in Maintenance ‑ Inspection
and Maintenance Schedule.

• Touch up any paint nicks. See your dealer for touch‑up paint.

• Spray Quicksilver or Mercury Precision Lubricants Corrosion Guard on
external metal surfaces (except corrosion control anodes).

Tube Ref

No.

Description Where Used Part No.

120

Corrosion Guard External metal surfaces 92-802878 55

Protecting Internal Engine Components

NOTE: Make sure the fuel system has been prepared for storage. Refer to

Fuel

System

, preceding.

IMPORTANT: Refer to Maintenance ‑ Spark Plug Inspection and Replacement
for correct procedure for removing spark plug boots.

• Place the outboard in water or connect flushing attachment for circulating
cooling water. Start the engine and let it run in neutral to warm up.

• With engine running at fast idle, stop the fuel flow by disconnecting the
remote fuel line. When engine begins to stall, quickly spray Quicksilver or
Mercury Precision Lubricants Storage Seal into carburetor until engine
stops from lack of fuel.

• Remove the spark plugs and inject a five second spray of storage seal
around the inside of the cylinder.

• Rotate the flywheel manually several times to distribute the storage seal
in the cylinder. Reinstall spark plug.

Gearcase

•

Drain and refill the gearcase lubricant. Refer to Changing Gear Oil.

Positioning Outboard for Storage

Store outboard in an upright (vertical) position to allow water to drain out of the
outboard.

NOTICE

Storing the outboard in a tilted position can damage the outboard. Water
trapped in the cooling passages or rain water collected in the propeller
exhaust outlet in the gearcase can freeze. Store the outboard in the full down
position.

STORAGE

eng 69

Battery Storage

• Follow the battery manufacturer's instructions for storage and charging.

• Remove the battery from the boat and check water level. Charge if
necessary.

• Store the battery in a cool, dry place.

• Periodically check the water level and charge the battery during storage.

STORAGE

70 eng

Starter Motor Will Not Crank the Engine (Electric Start Models)

POSSIBLE CAUSES

• Remote control models ‑ Blown 20 amp fuse in the starting circuit. Refer
to Maintenance section.

• Outboard is not shifted to neutral position.

• Weak battery or battery connections are loose or corroded.

• Ignition key switch failure.

• Wiring or electrical connection faulty.

• Starter motor or starter solenoid failure.

Engine Will Not Start

POSSIBLE CAUSES

• Lanyard stop switch not in "RUN" position.

•

Incorrect starting procedure. Refer to Operation section.

• Old or contaminated gasoline.

•

Engine flooded. Refer to Operation section.

• Fuel is not reaching the engine.

a. Fuel tank is empty.
b. Fuel tank vent not open or restricted.
c. Fuel line is disconnected or kinked.
d. Primer bulb not squeezed.
e. Primer bulb check valve is faulty.
f.

Fuel filter is obstructed. Refer to Maintenance section.
g. Fuel pump failure.
h. Fuel tank filter obstructed.

• Ignition system component failure.

•

Spark plugs fouled or defective. Refer to Maintenance section.

Engine Runs Erratically

POSSIBLE CAUSES

•

Spark plugs fouled or defective. Refer to Maintenance section.

• Incorrect setup and adjustments.

• Fuel is being restricted to the engine.

•

Engine fuel filter is obstructed. Refer to Maintenance section.

• Fuel tank filter obstructed.

• Stuck anti‑siphon valve on built in fuel tank.

• Fuel line is kinked or pinched.

• Fuel pump failure.

TROUBLESHOOTING

eng 71

• Ignition system component failure.

Performance Loss

POSSIBLE CAUSES

• Throttle not fully open.

• Damaged or improper size propeller.

• Incorrect engine timing, adjustments, or setup.

• Boat overloaded or load improperly distributed.

• Excessive water in bilge.

• Boat bottom is dirty or damaged.

Battery Will Not Hold Charge

POSSIBLE CAUSES

• Battery connections are loose or corroded.

• Low electrolyte level in battery.

• Worn out or inefficient battery.

• Excessive use of electrical accessories.

• Defective rectifier, alternator, or voltage regulator.

TROUBLESHOOTING

72 eng

Mercury Marine Validated Engine Mounting Hardware

IMPORTANT: Mercury Marine provides validated fasteners and installation
instructions, including torque specifications, with all of our outboards so they
can be properly secured to boat transoms. Improper installation of the outboard
can cause performance and reliability issues that can lead to safety concerns.
Follow all of the instructions relating to the outboard installation. DO NOT
mount any other accessory onto the boat with the fasteners provided with the
outboard. For example, do not mount tow sport bars or boarding ladders onto
the boat using the mounting hardware included with the outboard. Installing
other products onto the boat that utilize the outboard mounting hardware will
compromise the ability of that hardware to properly and safely secure the
outboard to the transom.

Outboards that require validated mounting hardware will have the following
decal on the transom clamp.

51965

Installing Outboard

NOTE: If outboard is a remote control electric start model, follow instructions in
the outboard installation manual (provided with the outboard) for installing
remote steering shift and throttle cables and remote wiring harness.

INSTALLING OUTBOARD ON TRANSOM

IMPORTANT: Most boats are rated and certified in terms of their maximum
horsepower, and this is shown on the boat's certification plate. Do not equip
your boat with an outboard that exceeds this limit. If in doubt, contact your
dealer. Do not operate the engine unit until it has been securely mounted on
the boat in accordance with the instructions below.

INSTALLATION

eng 73

1.

Single engine: Position the outboard motor at the center of the transom.
Mount it using a cushioning pad or plate.

a - Boat transom

2.

Twin engine: Position the outboard engines approximately 580 mm (22.8
in.) apart, measured from the centerline of each engine, and equal
distance (a) from the center of the transom.

a - Equal distance from the

center

3.

Transom matching: Be sure that the anti‑ventilation plate of the outboard
is below the water surface when running with the throttle wide open. If the
above condition cannot be met due to the shape of the bottom of the boat,
please consult the dealer.

IMPORTANT: If the anti‑ventilation plate is at a level higher than the bottom of
the boat, overheating may occur as a lack of cooling water flow in the cooling
systems.

37508

a

580 mm

37509

a

a

INSTALLATION

74 eng

4. Clearance between the anti‑ventilation plate of the motor and the bottom
of the boat must be 30–50 mm (1.2–2 in.). If the height difference exceeds
50 mm (2 in.), engine power performance is likely to be reduced as a
result of increased water resistance to the gearcase assembly.

a - Bottom of hull
b - Anti‑ventilation plate

5. Fasten the outboard by drilling two 7.9 mm (5/16 in.) holes through the
transom using transom clamp holes as a template. Fasten with two bolts,
flat washers, and locknuts. The use of clamp bracket screws alone is
insufficient to properly and safely secure the outboard to the transom. Use
a marine waterproofing sealer in holes and around bolts to make the
installation water tight.

a - Clamp bracket screw

!

WARNING

Failure to correctly fasten the outboard could result in the outboard propelling
off the boat transom resulting in property damage, serious injury, or death.
Before operation, the outboard must be correctly installed with the required
mounting hardware.

Installing the Remote Control Devices

It is recommended to consult with your dealer for installation and adjustment of
the remote control device.

1.

Installation of the remote control cables (box side): Follow the
instruction sheet provided with the remote control box.

30–50 mm (1.2” 2”)–

37510

a

b

42041

a

INSTALLATION

eng 75

2.

Installation of the remote control box: Follow the instruction sheet
provided with the remote control box.

37529

3. Installing of the remote control cable (engine side) and the harness
assembly (wiring harness).

a.

Fitting of throttle cable and shift cable guide:

•

Throttle side: Attach the throttle cable adapter to the end of the
cable and secure it with the nut.

a - Cable outer groove
b - Throttle cable
c - Nut
d - Spring
e - Throttle cable adapter
f - Ball holder

40468

a

b

c

d

e

f

INSTALLATION

76 eng

•

Shift side: Attach the shift cable adapter to the end of the cable
and secure it with the nut.

a - Cable outer groove
b - Shift cable
c - Nut
d - Shift cable adapter
e - Lock pin
f - Spring
g - Spring pin

b.

Fitting of remote control cable to the engine:

•

Throttle side: Set the throttle cable to the cable clip and
connect the throttle cable adapter to the ball joint of the
advancer arm.

40469

a

b

c

d

e

f

g

INSTALLATION

eng 77

•

Shift side: Set the shift cable to the cable clip and insert the
lock pin at the shift lever fitting hole and turn it 90° to lock it.

a - Cable of the shift side
b - Lock pin
c - Spring
d - Shift cable adapter
e - Spring pin
f - Shift lever
g - CDU
h - Advancer arm
i - Ball joint
j - Ball holder
k - Throttle cable adapter
l - Spring
m - Washer
n - Grommet is installed on the lower cowl
o - Cable of the throttle side
p - Cable outer groove

40470

a

b

c

d

e

f

g

h

i

j

k

l

m

n

o

p

q

r

s

t

u

INSTALLATION

78 eng

q - Cable clip
r - Lower cowl
s - Clamp
t - Steering hook plate
u - Shift cable clip

NOTE: Put the control lever in the Neutral (N) position and the neutral
warm‑up lever in the fully closed position.

NOTE: Confirm whether the engine side shift is in gear when shifting the
control lever of the remote control box to its first position in Forward (F) or
Reverse (R), about 32°, and whether the throttle of the carburetor is fully open
when shifting the lever further. Confirm whether the carburetor's throttle is fully
closed when the control lever is shifted to the Neutral (N) position. If it is not,
adjust the position of the ball holder.

c.

Connecting Electrical Harnesses

• Pass the cable assembly from the remote control box through
the hole in the lower cowl and connect the electric terminals.

INSTALLATION

eng 79

• Secure the cable assembly with the clamp according to the
drawing below.

a - Clamp
b - Starter solenoid
c - Fuse wire
d - Choke solenoid
e - Rectifier
f - From the remote control box
g - Battery cable
h - Cable assembly

Wire Color Code Abbreviations

Wire Color Abbreviations

BLK Black

BLU Blue
BRN Brown GRY Gray
GRN Green ORN or ORG Orange
PNK Pink PPL or PUR Purple
RED Red TAN Tan
WHT White YEL Yellow
LT or LIT Light DK or DRK Dark

40471

a

b

c

a

d

e

f

g

h

a

INSTALLATION

80 eng

Battery Installation

MOUNTING BATTERY

Follow the battery manufacturer's instructions carefully. Mount battery securely
to the hull in a place free from splashing water.

NOTE: Electric starting outboards must have the battery cables connected to a
battery whenever the engine is running, even if started manually, as damage to
the charging system could result.

BATTERY CONNECTIONS

Connect a red cable to the positive (+) terminal first and a black cable to the
negative (–) terminal of the battery. Put a red cap on the positive terminal.
When disconnecting battery cables, be sure to disconnect the black cable first,
and then the red cable.

Required battery rating: 12 V battery with a recommended capacity of 40 AH or
more.

• Battery cables must be long enough to allow free steering.

• Battery cables must be arranged and protected from damage during
steering.

• With poor cable connections, the starter will fail to start.

• Battery cable terminals should be clean, tight, and correctly installed.
Positive to positive and negative to negative.

• Battery must be fully charged before running the motor.

a - Red cable (+)
b - Black cable (–)

IMPORTANT: Please follow the instructions below:

• Hydrogen gas is generated when charging a battery. Keep the battery in a
well‑ventilated area during charging. Remove the battery from the boat;
this will protect your hull and interior from damage. Electric sparks,
cigarette smoking, and other sources of fire must be avoided in the
charging area to prevent explosion of the battery.

• The battery fluid (electrolyte) contains sulfuric acid. If electrolyte is spilled
on the skin or clothes, wash with plenty of water and consult a medical
doctor. Always use safety glasses and rubber gloves when handling the
battery.

37712

a

b

INSTALLATION

eng 81

Propeller Selection

The propeller supplied with your outboard provides the best overall
performance under average operating conditions.

A propeller must be selected so that the engine RPM when cruising with a
wide‑open throttle, is within the recommended range.

Model Wide‑open throttle RPM range

9.9 4500–5300 RPM

15/18 5200–5800 RPM

If changing conditions cause the RPM to drop below the recommended range,
such as warmer, more humid weather, operation at higher elevations,
increased boat load, or a dirty boat bottom/gearcase, a propeller change or
cleaning may be required to maintain performance and ensure the outboard's
durability.

Check full‑throttle RPM, using an accurate tachometer, with the engine trimmed
out to a balanced‑steering condition (steering effort equal in both directions)
without causing the propeller to break loose.

PROPELLER TABLE

A propeller must be selected so that the engine RPM measured at wide‑open
throttle while cruising is within the recommended range. Refer to Accessories
‑ Propeller Table of this manual.

INSTALLATION

82 eng

Propeller Table

Use a Mercury/Quicksilver propeller.
A propeller must be selected so that the engine RPM measured at wide‑open

throttle while cruising is within the recommended range: 9.9 HP = 4500–5300
RPM; 15/18 HP = 5200–5800 RPM.

Transom height: S = short, L = long, XL = extra long

Propeller Chart (Standard Equipment)

Propeller size 235 x 203 mm (9.2 x 8 in.) 235 x 229 mm (9.2 x 9 in.)

9.9 HP L, XL S
15 HP L, XL S
18 HP XL S, L

Propeller Chart

Propeller size

234 x 155 mm

(9.2 x 6 in.)

234 x 254 mm

(9.2 x 10 in.)

234 x 292 mm
(9.2 x 11.5 in.)

9.9 HP Optional Optional Optional
15 HP Optional Optional Optional
18 HP Optional Optional Optional

ACCESSORIES

eng 83

Accessories

OPTIONAL ACCESSORIES

40476

a

b

c

d

e

g

h

f

ACCESSORIES

84 eng

a - Tachometer unit kit
b - Tachometer
c - Mercury/Quicksilver grease (250 g)
d - Mercury/Quicksilver gear oil (500 ml)
e - Touch‑up paint
f - Mercury/Quicksilver engine oil (0.4 L, 1 L, 4 L, 20 L)
g - Flushing attachment
h - Extension cord for light (lights are available on the market)

ACCESSORIES

eng 85

MH Models

39493

a

b

c

d

e

f

g

h

i

j

k

l

m

o

p

q

r

n

WIRING DIAGRAMS

86 eng

a - Remote control box (optional)
b - Battery
c - Extension cord (optional)
d - Fuse
e - Rectifier
f - Extension cord for light (optional)
g - Receptacle plug (optional)
h - Lamp (12V 80W) [AC] (sold separately)
i - Tachometer (optional)
j - Tachometer, lead wire (optional)
k - Separate cord, yellow (optional)
l - Separate cord, white (optional)
m - Flywheel magneto
n - Spark plug
o - Ignition coil
p - CD unit
q - Lanyard stop switch
r - Stop cord (optional)

WIRING DIAGRAMS

eng 87

EH Models

39494

a

b

c

d

e

f

g

h

i

j

k

l

m

n

o

p

q

WIRING DIAGRAMS

88 eng

a - Main switch
b - Neutral switch
c - Starter motor
d - Starter cord
e - Starter solenoid
f - Fuse
g - Rectifier
h - Tachometer
i - Tachometer lead wire (optional)
j - Separate cord, yellow (optional)
k - Separate cord, white (optional)
l - Flywheel magneto
m - Spark plugs
n - Ignition coil
o - CDU
p - Lanyard stop switch
q - 12V 40AH or 12V 70AH (sold separately)

WIRING DIAGRAMS

eng 89

E Models

39495

a

b

c

d

e

k

j

i

q

h

g

f

l

m

n

o

p

t

r

s

WIRING DIAGRAMS

90 eng