Power Unit; Engine Will Not Start Or Is A Little Hard To Start - TOHATSU MFS 4D Service Manual

Before working on the outboard motor, check the hull, rigging, installation of outboard motor, fuel
level, and wire connections. For mechanical troubleshooting, refer to relevant troubleshooting
section in this chapter. For checking and servicing outboard motor, refer to service procedures
described in this manual to perform the work safely.

2. Power Unit

Trouble 1 Engine will not start or is a little hard to start. (Recoil starter operates normally.)
• Inspection of Ignition System, Fuel System and Compression Pressure
Check electrical conductivity of
stop switch.
(with lock plate attached)
Normal ?
YES
Use spark tester to check
ignition sparks.
Normal ?
YES
Check spark plug.
Good?
YES
Check compression pressure.
Out of specified
range?
YES
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4st 4/5/6 2020
• When testing, put electrode cap assuredly to prevent
direct contact with spark tester wiring and leak of
electrical current.
• Keep flammable gas, fuel and oil away from tester to
prevent them from catching sparks.
NO
Replace stop switch.
WARNING
NO
Check igniter and/or
plug cap.
NO
Clean spark plug
and adjust gap,
or replace with new one.
NO
Check fuel system.
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