Inspecting Idling Speed; Changing Engine Oil - Yamaha F250B Owner's Manual

1. Spark plug gap
2. Spark plug part number
3. Spark plug I.D. mark (NGK)
Spark plug gap:
1.0–1.1 mm (0.039–0.043 in)
5. When fitting the plug, wipe off any dirt
from the threads, and then screw it in to
the correct torque.
Spark plug torque:
25.0 Nm (2.55 kgf-m, 18.4 ft-lb)
TIP:
If a torque-wrench is not available when you
are fitting a spark plug, a good estimate of the
correct torque is 1/4 to 1/2 turn past finger-
tight. Have the spark plug adjusted to the cor-
rect torque as soon as possible with a torque-
wrench.
6. Install the ignition coil and tighten the
bolts.
Bolt tightening torque:
7.0 Nm (0.71 kgf-m, 5.2 ft-lb)
7. Install the ECM (Electronic control mod-
ule) cover and tighten the bolts.
Bolt tightening torque:
8.0 Nm (0.82 kgf-m, 5.9 ft-lb)
EMU35271

Inspecting idling speed

ECM01690
NOTICE
This procedure must be performed while
the outboard motor is in the water.
Perform this procedure using the Command
Link Tachometer. Results may vary depend-
ing on whether testing is conducted with the
outboard motor in the water.
1. Start the engine and allow it to warm up
fully in neutral until it is running smoothly.
2. Once the engine has warmed up, verify
whether the idle speed is set to specifica-
tion. For idle speed specifications, see
page 15.
EMU37492

Changing engine oil

ECM01710
NOTICE
Change the engine oil after the first 20
hours of operation or 3 months, and every
100 hours or at 1-year intervals thereafter.
Otherwise the engine will wear quickly.
The engine oil should be extracted with an oil
changer.
1. Put the outboard motor in an upright po-
sition (not tilted). NOTICE: If the motor
is not level, the oil level indicated on
the dipstick may not be accurate.
[ECM01860]
Maintenance
93