Mercury 15 MH - User Manual

i
Thank You
for your purchase of one of the finest outboards available. You
have made a sound investment in boating pleasure. Your
outboard has been manufactured by Mercury Marine, a world
leader in marine technology and outboard manufacturing
since 1939. These years of experience have been committed
to the goal of producing the finest quality products. This led to
Mercury Marine's reputation for strict quality control,
excellence, durability, lasting performance and being the best
at providing after the sale support.
Please read this manual carefully before operating your
outboard. This manual has been prepared to assist you in the
operation, safe use and care of your outboard.
All of us at Mercury Marine took pride in building your outboard
and wish you many years of happy and safe boating.
Again, thank you for your confidence in Mercury Marine.
EPA Emissions Regulations
Outboards sold by Mercury Marine in the United States are
certified to the United States Environmental Protection
Agency as conforming to the requirements of the regulations
for the control of air pollution from new outboard motors. This
certification is contingent on certain adjustments being set to
factory standards. For this reason, the factory procedure for
servicing the product must be strictly followed and, wherever
practicable, returned to the original intent of the design.
Maintenance, replacement, or repair of the emission
control devices and systems may be performed by any
marine engine repair establishment or individual.
Engines are labeled with an Emission Control Information
decal as permanent evidence of EPA certification.
!
WARNING
The engine exhaust from this product contains chemicals
known to the state of California to cause cancer, birth defects
or other reproductive harm.
© 2009 Mercury Marine 9.9/15/18 2 S (2-Stroke) 90-10263080 305

Mercury 15 MH Specifications

General

Cylinders	2
Starting System	Manual
Full Throttle RPM Range	5700-6200
Fuel Induction System	Carbureted
Gear Ratio	2.15:1
Gear Shift	F-N-R
Horsepower	15 hp (11.0 kW)
Fuel Type	Gasoline
Shaft Length	15 in (381 mm) / 20 in (508 mm)
Engine Type	4-Stroke SOHC

Summary

Warranty Information

FourStroke Outboard Limited Warranty

Warranty Coverage and Exclusions

Explains what is covered and not covered under the warranty, including general exclusions.

General Information

Before Operating Your Outboard

Operational Guidance and Safety

Boat Horsepower Capacity

Warning and guidance on adhering to the boat's maximum horsepower rating.

Safety Notices

Lanyard Stop Switch

Explanation of the lanyard stop switch function and its importance for safety.

Water Safety

Protecting People in the Water

Safety guidelines for preventing injury to swimmers and people in the water.

Operational Hazards

Wave and Wake Jumping

Impact with Underwater Hazards

How to reduce risk of injury or damage from striking underwater obstacles.

Specific Safety Instructions

Exhaust Emissions and Carbon Monoxide

Awareness and precautions regarding carbon monoxide poisoning from engine exhaust.

Component Identification

MH Models Component Identification

EH Models Component Identification

E Models Component Identification

INSTALLATION

Installing Outboard on Transom

Step-by-step guide for securely mounting the outboard motor onto the boat's transom.

Installing Remote Control Devices

Instructions for installing remote control cables and components for steering and throttle.

Connecting Electrical Harnesses

Procedure for connecting the electrical harness from the remote control box to the engine.

Battery Installation

Guidelines for safely mounting and connecting the 12V battery for electric start models.

Propeller Selection

TRANSPORTING

Removing and Carrying the Motor

Procedures for safely removing, carrying, and storing the outboard motor.

Trailering Boat;Outboard

Fuel Tank Transport

Transporting Portable Fuel Tanks

Safety instructions and procedures for transporting portable fuel tanks.

FUEL AND OIL

Fuel Recommendations

Guidelines on acceptable gasoline types, octane ratings, and issues with alcohol content.

Oil Recommendation

Specifies the recommended engine oil type (TCW-3) and mixing ratios.

ENGINE BREAK-IN

Detailed procedure and schedule for the initial engine break-in period.

OPERATION

Pre-Starting Check List

Essential checks to perform before starting the engine for safe operation.

Warming Up the Engine

Starting The Engine

Step-by-step guide for starting the outboard engine, including choke and throttle operation.

Gear Shifting

Correct procedures for shifting the outboard into forward, reverse, and neutral gears.

Stopping The Engine

Emergency Starting

MAINTENANCE

Outboard Care

Inspection and Maintenance Schedule

Periodic inspection tasks to be performed before, after use, and at specific hour intervals.

Flushing The Cooling System

Fuel System Maintenance

Fuse Replacement

Propeller Replacement

Spark Plug Inspection and Replacement

Changing gear oil

STORAGE

Storage Preparation

Protecting External Outboard Components

Protecting Internal Engine Components

TROUBLESHOOTING

Starter Motor Will Not Crank

Potential causes and solutions if the electric start motor fails to crank the engine.

Engine Will Not Start

Troubleshooting steps for common reasons why the engine fails to start.

Engine Runs Erratically

Performance Loss

Battery Will Not Hold Charge