Mercury 100 FourStroke, Service Manual

Page: 2 / 574

i 90-830234R3 DECEMBER 1997
Notice
Throughout this publication, “Dangers”, “Warnings”
and “Cautions” (accompanied by the International
HAZARD Symbol
) are used to alert the mechanic
to special instructions concerning a particular service
or operation that may be hazardous if performed in-
correctly or carelessly.
OBSERVE THEM CARE-
FULLY!
These “Safety Alerts” alone cannot eliminate the haz-
ards that they signal. Strict compliance to these spe-
cial instructions when performing the service, plus
“Common Sense” operation, are major accident pre-
vention measures.
DANGER
DANGER - Immediate hazards which WILL result
in severe personal injury or death.
WARNING
WARNING - Hazards or unsafe practices which
COULD result in severe personal injury or death.
CAUTION
Hazards or unsafe practices which could result
in minor personal injury or product or property
damage.
Notice to Users of This
Manual
This service manual has been written and published
by the Service Department of Mercury Marine to aid
our dealers’ mechanics and company service per-
sonnel when servicing the products described here-
in.
It is assumed that these personnel are familiar with
the servicing procedures of these products, or like or
similar products manufactured and marketed by
Mercury Marine, that they have been trained in the
recommended servicing procedures of these prod-
ucts which includes the use of mechanics’ common
hand tools and the special Mercury Marine or recom-
mended tools from other suppliers.
We could not possibly know of and advise the service
trade of all conceivable procedures by which a ser-
vice might be performed and of the possible hazards
and/or results of each method. We have not under-
taken any such wide evaluation. Therefore, anyone
who uses a service procedure and/or tool, which is
not recommended by the manufacturer, first must
completely satisfy himself that neither his nor the
products safety will be endangered by the service
procedure selected.
All information, illustrations and specifications con-
tained in this manual are based on the latest product
information available at the time of publication. As re-
quired, revisions to this manual will be sent to all deal-
ers contracted by us to sell and/or service these prod-
ucts.
It should be kept in mind, while working on the prod-
uct, that the electrical system and ignition system are
capable of violent and damaging short circuits or se-
vere electrical shocks. When performing any work
where electrical terminals could possibly be
grounded or touched by the mechanic, the battery
cables should be disconnected at the battery.
Any time the intake or exhaust openings are exposed
during service they should be covered to protect
against accidental entrance of foreign material which
could enter the cylinders and cause extensive inter-
nal damage when the engine is started.
It is important to note, during any maintenance proce-
dure replacement fasteners must have the same
measurements and strength as those removed.
Numbers on the heads of the metric bolts and on the
surfaces of metric nuts indicate their strength. Ameri-
can bolts use radial lines for this purpose, while most
American nuts do not have strength markings. Mis-
matched or incorrect fasteners can result in damage
or malfunction, or possibly personal injury. There-
fore, fasteners removed should be saved for reuse in
the same locations whenever possible. Where the
fasteners are not satisfactory for re-use, care should
be taken to select a replacement that matches the
original.
Cleanliness and Care of
Outboard Motor
A marine power product is a combination of many
machined, honed, polished and lapped surfaces with
tolerances that are measured in the ten thousands of
an inch./mm. When any product component is serv-
iced, care and cleanliness are important. Throughout
this manual, it should be understood that proper
cleaning, and protection of machined surfaces and
friction areas is a part of the repair procedure. This is
considered standard shop practice even if not specif-
ically stated.