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4-12
Outboard motor troubleshooting
Symptom 1: Unstable engine idle speed, poor acceleration, poor performance, or limited
engine speed.
Fuel not supplied
(all cylinders)
—
Measure the fuel pressure.
Clogged filter
Check the fuel filter for dirt and obstruc-
tions.
Fuel leakage
Check the fuel line for leakage.
High-pressure fuel pump mal-
function
Check the high-pressure fuel pump oper-
ation using the YDIS.
Measure the high-pressure fuel pump
resistance.
Main relay malfunction
Check the main relay.
Short, open, or loose connec-
tion in high-pressure fuel pump
circuit
Measure the high-pressure fuel pump
input voltage.
Check for wiring harness continuity
between the high-pressure fuel pump
and the main relay.
Check for wiring harness continuity
between the high-pressure fuel pump
and engine ECM.
Fuel pump malfunction
Check the fuel pump for leakage.
Check the diaphragm for tears.
Check the camshaft.
Y-COP is locked.
Unlock Y-COP.
Compression pressure
is low
Improper valve timing
Check the timing belt.
Compression leakage
Measure the compression pressure.
Check the valve for bends or sticking.
Check the piston and piston rings for
damage.
Check the cylinder for scratches.
—
Intake air passage malfunction
Check the ISC valve for sticking.
Check the intake manifold and throttle
body for air leakage.
Symptom 2
Cause
Checking steps
See
page
Throttle valve does not
move properly
Throttle valve malfunction
Check the throttle valve for proper move-
ment.
Throttle valves do not synchro-
nize.
Synchronize the throttle valves.
Throttle link and throttle cable
are not installed properly.
Adjust the throttle link and throttle cable.
Symptom 2
Cause
Checking steps
See
page
Summary of Contents for F150A
Page 1: ...SERVICE MANUAL 63P 28197 3P 12 F150A FL150A F150B FL150B ...
Page 4: ......
Page 48: ...2 3 Electronic control system Engine ECM component 2 3 4 6 5 1 8 7 10 9 11 12 14 15 16 13 17 ...
Page 110: ...3 41 Propeller selection MEMO ...
Page 129: ...4 18 Outboard motor troubleshooting MEMO ...
Page 175: ...5 44 PTT system 0 1 2 3 4 5 6 7 8 9 10 A MEMO ...
Page 247: ...7 22 Starter motor Terminal nut 3 9 N m 0 9 kgf m 6 6 ft lb ...
Page 385: ...8 78 Shimming counter rotation model 0 1 2 3 4 5 6 7 8 9 10 A MEMO ...
Page 449: ...9 62 PTT gear pump 0 1 2 3 4 5 6 7 8 9 10 A MEMO ...
Page 474: ...i 8 Index 0 1 2 3 5 6 7 8 9 10 10 A MEMO ...
Page 475: ......
Page 476: ...Oct 2011 2 ABE E ...