Yamaha F350B - Page 152

4-25
Outboard motor troubleshooting
Fuel not supplied (all
cylinders)
Pinched or kinked fuel hose Check the fuel hose. 2-46
Fuel leakage Check the fuel line for leakage. 2-46
Clogged fuel filter element
Check the fuel filter element for dirt
and obstructions.
6-7
Blown fuse Check the fuse. 5-5
High-pressure fuel pump
malfunction
Check the high-pressure fuel pump
operation using the YDIS.
5-32
Measure the high-pressure fuel
pump resistance.
5-32
Short, open, or loose con-
nection in high-pressure
fuel pump circuit
Check the high-pressure fuel pump
input voltage.
5-32
Check for wiring continuity between
the high-pressure fuel pump relay
and the engine ECM.
A-11
Check for wiring continuity between
the high-pressure fuel pump and the
high-pressure fuel pump relay.
A-11
Check for wiring continuity between
the high-pressure fuel pump and
ground.
A-11
Low-pressure fuel pump
malfunction
Check the low-pressure fuel pump
operation using the YDIS.
5-32
Check the low-pressure fuel pump
resistance.
5-32
Short, open, or loose con-
nection in low-pressure fuel
pump circuit
Check the low-pressure fuel pump
input voltage.
5-32
Check for wiring continuity between
the low-pressure fuel pump and the
engine ECM.
A-11
Check for wiring continuity between
the low-pressure fuel pump and the
main relay.
A-11
Compression pres-
sure is low
Improper valve timing
Check the valve timing. 7-35
Check the timing belt. 7-35
Compression leakage
Check the valve for bends and stick-
ing.
7-51
Check the piston and piston rings for
damage.
7-71
Check the cylinder for scratches. 7-73
Symptom 2 Cause Checking steps
See
page