Yamaha F50 Service Manual

							62Y3A113-6
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2. Place a drain pan under the drain hole,
and then remove the drain bolt 2
 and let
the oil drain completely.
3. Place a rag under the oil filter, and then
remove the filter.
NOTE:
Be sure to clean up any oil spills.
4. Apply a thin coat of the new engine oil to
the O-ring of the new oil filter.
5. Install the oil filter, and then tighten it to
the specified torque.6. Install the drain bolt, and then tighten it to
the specified torque.
7. Fill the specified engine oil into the oil
filler hole. Oil filter wrench: YU-38411 / 90890-01426
S62Y3080
2
S62Y3100
Oil filter wrench: YU-38411 / 90890-01426
Oil filter: 18 N·m (1.8 kgf·m, 13 ft·lb)
Drain bolt: 18 N·m (1.8 kgf·m, 13 ft·lb)
Recommended engine oil:
4-stroke motor oil
API: SE, SF, SG, or SH
SAE: 10W-30, 10W-40, or 20W-40
S62Y3110
E
S62Y3115
Fuel system / Power unit 
						

							CHK 
ADJ
Periodic checks and adjustments
3-762Y3A11
8. Install the oil filler cap and dipstick, and
then start the engine and warm it up for 5
minutes.
9. Turn the engine off, and then check the
oil level and correct it if necessary.
Checking the timing belt
1. Remove the flywheel magnet cover.
2. While turning the flywheel magnet clock-
wise, check the interior a
 and the exte-
rior b
 of the timing belt for cracks,
damage, or wear. Replace if necessary.
CAUTION:
Do not turn the flywheel magnet counter-
clockwise, otherwise the valve system
may be damaged.
Replacing the timing belt
1. Turn the flywheel magnet clockwise and
align the “1” mark a
 on the driven
sprocket with the “” mark b
 on the cyl-
inder head.
CAUTION:
Do not turn the flywheel magnet counter-
clockwise, otherwise the valve system
may be damaged.
2. Remove the flywheel magnet. Oil quantity:
With oil filter replacement:
2.2 L (2.3 US qt, 1.9 Imp qt)
Without oil filter replacement:
2.0 L (2.1 US qt, 1.8 Imp qt) 
						

							62Y3A113-8
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ÈFor USA and Canada
ÉFor worldwide
CAUTION:
•Apply force in the direction of the
arrows shown, to prevent the flywheel
holder from slipping off easily.
•To prevent damage to the engine or
tools, screw in the flywheel puller set
bolts evenly and completely so that the
flywheel puller plate is parallel to the fly-
wheel magnet.
NOTE:
Apply force to the crankshaft end until the fly-
wheel magnet comes off the tapered portion
of the crankshaft.3. Disconnect the stator couplers 3
, and
then remove the stator 4
.
4. Disconnect the pulser coil coupler 5
,
and then remove the stator base 6
 with
both collars 7
.
5. Remove the blowby hose bolts 8
 and
tensioner 9
, then the timing belt 0
 from
the driven sprocket side.
Flywheel magnet holder 1
: YB-06139
Flywheel holder 1
: 90890-06522
Universal puller 2
: YB-06117
Flywheel puller 2
: 90890-06521
Power unit 
						

							CHK 
ADJ
Periodic checks and adjustments
3-962Y3A11
6. Check that the “1” mark a
 on the driven
sprocket is aligned with the “” mark b
on the cylinder head, and that the “”
mark c
 on the drive sprocket is aligned
with the “” mark d
 on the crankcase.
Align if necessary.
CAUTION:
Do not turn the sprockets counterclock-
wise, otherwise the valve system may be
damaged.
7. While pushing against the tensioner side
of the belt, install the new timing belt from
the drive sprocket side with its part num-
ber in the upright position.
CAUTION:
•Do not twist, turn inside out, or bend the
timing belt beyond the maximum limit of
25 mm (1.0 in) e
, otherwise it may be
damaged.
•Do not get oil or grease on the timing
belt.
8. Install the tensioner and bolts, and then
tighten the bolts finger tight.
9. Turn the drive sprocket clockwise two
turns, and then check that the alignment
marks are aligned.
CAUTION:
Do not turn the sprockets counterclock-
wise, otherwise the valve system may be
damaged.
10. Tighten the tensioner bolts to the speci-
fied torque.
11. Install the blowby hose bolts, stator base
with both collars and stator, and then
connect the couplers.
12. Install the Woodruff key.
Tensioner bolt:
8 N·m (0.8 kgf·m, 5.8 ft·lb)
Tensioner bolt (adjusting bolt):
25 N·m (2.5 kgf·m, 18 ft·lb)
Stator base screw:
4 N·m (0.4 kgf·m, 2.9 ft·lb) 
						

							62Y3A113-10
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13. Install the flywheel magnet and flywheel
magnet cover.
ÈFor USA and Canada
ÉFor worldwide
CAUTION:
Apply force in the direction of the arrows
shown, to prevent the flywheel holder
from slipping off easily.
NOTE:
Apply engine oil to the flywheel magnet nut
before installation.
Checking the valve clearance
1. Remove the flywheel magnet cover, and
then disconnect the high-tension cords
and blowby hose 1
.2. Remove the spark plugs, fuel pump 2
,
and cylinder head cover 3
.
3. Turn the flywheel clockwise and align the
“1” mark a
 on the driven sprocket with
the “” mark b
 on the cylinder head.
CAUTION:
Do not turn the flywheel counterclock-
wise, otherwise the valve system may be
damaged.
4. Check the intake valve clearance for cyl-
inders #1 and #2, and the exhaust valve
clearance for cylinders #1 and #3. Adjust
if necessary. Flywheel magnet holder: YB-06139
Flywheel holder: 90890-06522
Flywheel magnet nut:
160 N·m (16 kgf·m, 116 ft·lb)
Power unit 
						

							CHK 
ADJ
Periodic checks and adjustments
3-1162Y3A11
5. Turn the flywheel clockwise and align the
“4” mark c
 on the driven sprocket with
the “” mark b
 on the cylinder head.
CAUTION:
Do not turn the flywheel counterclock-
wise, otherwise the valve system may be
damaged.
6. Check the intake valve clearance for cyl-
inders #3 and #4, and the exhaust valve
clearance for cylinders #2 and #4. Adjust
if out of specification.
NOTE:
Adjust the valve clearance when the engine
is cold.
7. Loosen the locknut 4
, and then turn the
adjusting screw 5
 until the specified
valve clearance is obtained.
NOTE:
To decrease the valve clearance, turn the
adjusting screw clockwise.
To increase the valve clearance, turn the
adjusting screw counterclockwise.
8. Tighten the locknut, and then check the
valve clearances. Adjust if necessary.
9. Install the cylinder head cover, fuel
pump, and spark plugs.
10. Connect the blowby hose and high-ten-
sion cords, and then install the flywheel
magnet cover.
Checking the spark plugs
1. Disconnect the high-tension cords, and
then remove the spark plugs.
Valve clearance:
Intake d
:
0.20 ±
 0.05 mm (0.008 ±
 0.002 in)
Exhaust e
:
0.30 ±
 0.05 mm (0.012 ±
 0.002 in) 
						

							62Y3A113-12
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2. Clean the electrodes 1
 with a spark plug
cleaner or wire brush. Replace the spark
plug if necessary.
3. Check the electrodes for erosion and
excessive carbon or other deposits, and
the gasket for damage. Replace the
spark plug if necessary.
4. Check the spark plug gap a
. Adjust if out
of specification.
5. Install the spark plug, tighten it finger
tight b
, then to the specified torque with
a spark plug wrench c
.
Checking the thermostat
1. Remove the cover 1
, thermostat cover
2
, and thermostat 3
.
2. Suspend the thermostat in a container of
water.
3. Place a thermometer in the water and
slowly heat the water.
Specified spark plug: DPR6EA-9 (NGK)
Spark plug gap a
: 0.9 mm (0.035 in)
Spark plug: 18 N·m (1.8 kgf·m, 13 ft·lb)
S62Y3290
3
2
1
S62Y3300
Power unit 
						

							CHK 
ADJ
Periodic checks and adjustments
3-1362Y3A11
4. Check the thermostat valve opening at
the specified water temperatures.
Replace if out of specification.
5. Install the thermostat, new gasket, ther-
mostat cover, and cover.
Checking the cooling water passage
1. Check the cooling water inlet cover 1
and cooling water inlet for clogs. Clean if
necessary.
2. Place the lower unit in water, and then
start the engine.3. Check for water flow at the cooling water
outlet. If there is no water flow, check the
cooling water passage inside the out-
board.
Control system3
Checking the throttle cable operation
1. Check that the throttle cam 1
 is at the
fully closed position a
 when the remote
control lever is in neutral or the throttle
grip is fully closed. Adjust the throttle
cable length if necessary as follows.
2. Loosen the locknut 2
, remove the clip
3
, and then disconnect the throttle cable
joint 4
. Water temperature Valve lift a
 
below 
60 °C (140 °F)0 mm (0 in)
above 
70 °C (158 °F)more than 
3 mm (0.12 in)
S62Y3320
1 1
S62Y33701 
						

							62Y3A113-14
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3. Align the alignment mark b
 on the throt-
tle cam 1
 with the alignment mark c
 on
the shift bracket.
4. Adjust the position of the throttle cable
joint until its hole is aligned with the set
pin d
 on the throttle cam.
CAUTION:
The throttle cable joint must be screwed
in a minimum of 8.0 mm (0.31 in) e
.
5. Connect the cable joint, install the clip,
and then tighten the locknut.
6. Check the throttle cable for smooth oper-
ation and adjust the cable length, if nec-
essary, repeating steps 2–6.
Checking the gearshift operation
1. Check that the gearshift operates
smoothly when shifting from neutral into
forward and reverse. Adjust the shift
cable length if necessary.
2. Set the gearshift to the neutral position.
3. Loosen the locknut 1
, remove the clip
2
, and then disconnect the shift cable
joint 3
.4. Align the set pin a
 in the center of the
shift bracket with the alignment mark b
on the bracket.
5. Adjust the position of the shift cable joint
until its hole is aligned with the set pin.
CAUTION:
The shift cable joint must be screwed in a
minimum of 8.0 mm (0.31 in) c
.
6. Connect the cable joint, install the clip,
and then tighten the locknut.
7. Check the gearshift for smooth operation
and adjust the shift cable length, if nec-
essary, repeating steps 3–6.
S62Y3400
S62Y3360
Power unit / Control system 
						

							CHK 
ADJ
Periodic checks and adjustments
3-1562Y3A11
Checking the engine idle speed
1. Start the engine and warm it up for 5 min-
utes.
2. Attach the special service tool to high-
tension cord #1 1
, and then check the
engine idle speed. Adjust if out of specifi-
cation.
3. Turn the throttle stop screw 2
 in direc-
tion a
 or b
 until the specified engine
idle speed is obtained.
NOTE:
To increase the idle speed, turn the throttle
stop screw in direction a
.
To decrease the idle speed, turn the throttle
stop screw in direction b
.
4. After adjusting the idle speed, rev the
engine a few times and let it idle for at
least 15 seconds to check the stability of
the engine.
Checking the ignition timing
1. Start the engine and warm it up for 5 min-
utes.
2. Attach the special service tool to high-
tension cord #1 1
, and then check the
engine idle speed.
3. Attach the special service tool to high-
tension cord #1 1
. Inductive self-powered tachometer:
YU-08036-B
Digital tachometer: 90890-06760
Engine idle speed: 
750 ±
 50 (950 ±
 50) r/min
S62Y3410
1
Inductive self-powered tachometer:
YU-08036-B
Digital tachometer: 90890-06760
Engine idle speed: 
750 ±
 50 (950 ±
 50) r/min
Battery powered timing light: YM-33277-A
Timing light: 90890-03141
S62Y3430
1
S62Y3440
1
S62Y3450