Trouble Recovery; Troubleshooting - Yamaha F4 Owner's Manual

EMU39523

Troubleshooting

This section describes the likely causes and
remedies for problems, such as those in the
fuel, compression, and ignition systems, poor
starting, and loss of power. Please note that
all of the items in this section may not apply to
your model.
If your outboard motor requires repair, bring it
to a Yamaha dealer.
Engine will not start.
Q. Is fuel tank empty?
A. Fill tank with clean, fresh fuel.
Q. Is fuel contaminated or stale?
A. Fill tank with clean, fresh fuel.
Q. Is fuel filter clogged?
A. Clean or replace filter.
Q. Is fuel pump malfunctioning?
A. Have serviced by a Yamaha dealer.
Q. Is spark plug fouled or of incorrect type?
A. Inspect spark plug. Clean or replace with
recommended type.
Q. Is spark plug cap fitted incorrectly?
A. Check and re-fit cap.
Q. Is spark plug wiring damaged or poorly
connected?
A. Check wires for wear or breaks. Tighten all
loose connections. Replace worn or broken
wires.
Q. Are electrical parts malfunctioning?
A. Have serviced by a Yamaha dealer.
Q. Is clip on engine shut-off cord (lanyard) in-
stalled?

Trouble Recovery

A. Install clip to engine shut-off switch.
Q. Are engine inner parts damaged?
A. Have serviced by a Yamaha dealer.
Engine idles irregularly or stalls.
Q. Is fuel system obstructed?
A. Check for pinched or kinked fuel line or oth-
er obstructions in fuel system.
Q. Is fuel contaminated or stale?
A. Fill tank with clean, fresh fuel.
Q. Is fuel filter clogged?
A. Clean or replace filter.
Q. Are electrical parts malfunctioning?
A. Have serviced by a Yamaha dealer.
Q. Is spark plug gap incorrect?
A. Replace spark plug.
Q. Is spark plug wiring damaged or poorly
connected?
A. Check wires for wear or breaks. Tighten all
loose connections. Replace worn or broken
wires.
Q. Is specified engine oil not being used?
A. Check and replace oil with specified type.
Q. Is thermostat malfunctioning or clogged?
A. Have serviced by a Yamaha dealer.
Q. Are carburetor adjustments incorrect?
A. Have serviced by a Yamaha dealer.
Q. Is fuel pump malfunctioning?
A. Have serviced by a Yamaha dealer.
Q. Is air vent screw tightened?
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