Yamaha F4B - Outboard Motor Troubleshooting Procedure; Power Unit Troubleshooting

4-1
TRBL
SHTG
Troubleshooting
Outboard motor troubleshooting
Troubleshooting procedure
1. Before troubleshooting the outboard motor, make sure that fresh fuel of the specified type has
been used.
2. Make sure that all electrical connections are secure and free from corrosion.
3. If the outboard motor is equipped with the charging system (optional for European market),
check that the battery is fully charged.
Troubleshooting the power unit
Troubleshooting consists of the following 3 items:
Symptom 1: Specific trouble conditions
Symptom 2: Trouble conditions of an area or individual part
Cause: Trouble causes of symptom 2
— : Not applicable
Symptom 1: Engine does not crank.
Symptom 1: Engine will not start (engine cranks).
Symptom 2 Cause Checking step
See
page
Starter handle cannot be
pulled
Gear shift not in the N position Set the gear shift to the N position. 10-4
Start-in-gear protection cable
not adjusted properly
Adjust the start-in-gear protection cable.
7-10
Manual starter malfunction Disassemble and check the manual
starter.
7-7
Decompressor malfunction Check the camshaft. 7-44
Stuck piston or crankshaft Disassemble and check the power unit. 7-21
7-39
Stuck drive shaft Disassemble and check the lower unit. 8-7
8-10
Starter handle can be
pulled, but the engine
does not crank
Manual starter malfunction Disassemble and check the manual
starter.
7-7
Damaged flywheel magnet
Woodruff key
Check the flywheel magnet Woodruff
key.
7-18
Symptom 2 Cause Checking step
See
page
Spark plug does not
spark
— Check the ignition spark. 5-5
Spark plug malfunction Check the spark plug. 7-35
Spark plug cap malfunction Check the spark plug cap. 5-5
Engine shut-off switch malfunc-
tion
Check the engine shut-off switch.
5-6
Fuel not supplied Fuel cock closed Set the fuel cock to the proper position. —
Clogged fuel strainer Check the fuel strainer for clog or dirt. 6-6
Fuel leakage Check the fuel line for fuel leakage. 6-1
Fuel pump malfunction Check the fuel pump for fuel leakage. 6-22
Check the diaphragm for tears. 6-23
Check the camshaft for wear. 7-44
Carburetor malfunction Disassemble and clean the carburetor. 6-18