Yamaha F2 5 Service Manual

							69M3E114-2
1
2
3
4
5
6
7
8
9
Hose routing4
Fuel and blowby hoses
1Fuel hose
2Blowby hose
3Blowby hose
S69M4000
1
2
3
Special service tools / Hose routing 
						

							FUELFuel system
4-369M3E11
Fuel tank4
No. Part name Q’ty Remarks
1 Fuel tank 1
2 Fuel filter 1
3 Fuel filler cap 1
4 Stopper 2
5 Chain 1
6 Stopper 1
7Gasket 1
8Bolt 3 M6 
× 35 mm
9Grommet 3
10 Collar 3
11 Clip 1
12 Fuel hose 1
13 Damper 1
14 Clip 1
S69M4010
13 14
12
1129
10 8
13
4
7 6
5 
						

							69M3E114-4
1
2
3
4
5
6
7
8
9
Carburetor and intake silencer4
No. Part name Q’ty Remarks
1 Carburetor 1
2 Intake silencer 1
3 Blowby hose 1
4Bolt 2 M6 
× 75 mm
5 Collar 2
6O-ring 1
Not reusable
7 Plastic tie 1Not reusable
8Hose 1
9 Fuel cock 1
10 Gasket 1
Not reusable
11 Gasket 1
12 Gasket 1
Not reusable
13 Throttle cable 1
14 O-ring 1
15 Fuel cock lever 1
16 Screw 1ø5 
× 7 mm
S69M4020
13
7
8
3
4 5 2 6
9 1 10 11 12
15 1614 13
Fuel tank / Carburetor and intake silencer 
						

							FUELFuel system
4-569M3E11
Carburetor4
No. Part name Q’ty Remarks
1 Carburetor body 1
2Screw 3ø4 
× 10 mm
3 Cover 1
4Gasket 1
Not reusable
5Screw 1ø4 
× 8 mm
6O-ring 1
Not reusable
7 Fuel cock 1
8 Main nozzle 1
9 Main jet 1
10 Pilot jet 1
11 Bushing 1
12 Float 1
13 Float pin 1
14 Screw 1ø4 
× 5 mm
15 Needle valve 1
16 Gasket 1
Not reusable
17 Float chamber 1
S69M4032
18 1917 161514 1311 10 8
9
12
5
7 6 1 432
20
21
22 È
AA
22
AA 
						

							69M3E114-6
1
2
3
4
5
6
7
8
9
4
ÈFor Europe No. Part name Q’ty Remarks
18 Screw 2ø4 
× 10 mm
19 Drain screw 1
20 Spring 1
21 O-ring 1
Not reusable
22 Pilot screw 1
S69M4032
18 1917 161514 1311 10 8
9
12
5
7 6 1 432
20
21
22 È
AA
22
AA
Carburetor 
						

							FUELFuel system
4-769M3E11
Draining the fuel
 WARNING
Before removing the fuel tank, fuel hose,
and carburetor, let the fuel drain com-
pletely.
1. Loosen the air vent screw 1
 attached to
the fuel filler cap.
2. Set the fuel cock lever 2
 to the open
position.
3. Place a drain pan under the drain hose,
and then loosen the drain screw and let
the fuel drain completely.
Checking the fuel tank and fuel filler 
cap
1. Check the fuel tank and fuel filler cap for
cracks, leaks, or damage. Replace if nec-
essary.
Checking the fuel filter
1. Check the fuel filter for dirt or residue.
Clean if necessary.
Checking the fuel cock
1. Check the fuel cock for leaks. Replace
the O-ring 1
 or fuel cock if necessary.
Checking the carburetor
1. Check the air and fuel passages, and jets
for dirt and foreign matter. Clean the car-
buretor body with a petroleum based sol-
vent if necessary.
S69M4240
S69M4040
S69M4055
S69M4250
1 
						

							69M3E114-8
1
2
3
4
5
6
7
8
9
2. Blow compressed air into all passages
and jets.
CAUTION:
•Direct the compressed air downward,
otherwise cleaning solvent may be
blown into your eyes or small parts of
the carburetor may be blown off.
•Do not use steel wire for cleaning the
jets, otherwise the jet diameters may be
enlarged, which may seriously affect
performance.
3. Check the main jet 1
, pilot jet 2
, and
main nozzle 3
 for dirt or residue. Clean if
necessary.
4. Check the pilot screw and needle valve
for bends or wear. Replace if necessary.5. Check the float for deterioration. Replace
if necessary.
6. Measure the float height a
. Adjust the
float height by bending the tab 4
 if out of
specification.
NOTE:
The float should be resting on the needle
valve 5
, but not compressing it.
Take measurements at the end of the float
opposite its pivoted side.
S69M4060
2
3
1
Float height a
:
10.5–11.5 mm (0.413–0.453 in)
S69M4090
S69M4100
4
5
a
Carburetor 
						

							FUELFuel system
4-969M3E11
Assembling the carburetor
1. Install the main nozzle 1
, main jet 2
,
pilot jet 3
, and bushing 4
 to the carbu-
retor body as shown.
2. Install the needle valve 5
, float 6
, float
pin 7
, and screw 8
 as shown, and then
check the float for smooth operation.
NOTE:
Place the needle valve in the valve seat
when installing the float to the carburetor
body.
Fit the float pin into the slit on the carbure-
tor body and lock it with the screw.
3. Install the pilot screw 9
, turn it in until it
is lightly seated, then out the specified
number of turns.
ÈFor Europe
Installing the carburetor
1. Install the carburetor to the power unit.
NOTE:
Align the projections 
a of gaskets 1
, 2
, and
3
, and then install the carburetor.
S69M4110
2
1 4
3
S69M4120
7
5 6 8
Pilot screw wrench 0: 90890-03154
Pilot screw setting: 2–3 turns out
S69M4130
È
9
0
9
S69M4140
1
2
3
S69M4150
a
1
23 
						

							69M3E114-10
1
2
3
4
5
6
7
8
9
2. Install the choke wire 4
 to the choke
lever 5
 of carburetor.
Installing the throttle cable
1. Turn the throttle grip to the fully closed
position.
2. Make the inner wire 1
 of the throttle
cable taut, and then connect the throttle
link 2
.
3. Check that the throttle link 2
 contacts
the fully open stopper a
 when the throt-
tle grip is turned from the fully closed
position to the fully open position.
Adjusting the pilot screw
1. Start the engine and warm it up for 5 min-
utes.
2. Attach the special service tool to the
spark plug wire 1
.
S69M4180
2
1
Digital tachometer: 90890-06760
S69M4190
a
2
Carburetor 
						

							FUELFuel system
4-1169M3E11
3. Turn the pilot screw 2
 in direction a
until it is lightly seated, then in direction
b
 to the specified number of turns.
ÈFor Europe
4. Turn the throttle stop screw 4
 in direc-
tion c
 or d
 until the specified engine
idle speed is obtained.
NOTE:
To increase the idle speed, turn the throttle
stop screw in direction c
.
To decrease the idle speed, turn the throttle
stop screw in direction d
.
5. 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.
Pilot screw wrench 3
: 90890-03154
Pilot screw setting: 2–3 turns out
Engine idle speed:
1,800–2,000 r/min
S69M4200
È È
bab
a
22
3