Yamaha Waverunner 3 Manual

							4-12
EFUELFUEL INJECTION SYSTEM
EXPLODED DIAGRAM
Step Procedure/Part name Q’ty Service points
18 Grommet 1
19 Throttle body joint 4
20 Band 2
21 Bolt 2
22 Air filter case stay 1 2
23 Band 1
24 Bolt 1
25 Air filter case stay 2 1
Reverse the removal steps for installation.
3165
15 14 2423 25
10
18
1797
6
13
12
8
11
22
21
4
1920LT
271
LT
242
LT
271
12
LT
572
LT
LT
242
8 × 35 mm
2nd   18 N • m (1.8 kgf 
• m, 13 ft 
• Ib) 1st    8.8 N • m (0.88 kgf 
• m, 6.4 ft 
• Ib)
6 × 16 mm
2nd   7.6 N • m (0.76 kgf 
• m, 5.5 ft 
• Ib) 1st    3.8 N • m (0.38 kgf 
• m, 2.7 ft 
• Ib)
6 × 16 mm
2nd   7.6 N • m (0.76 kgf 
• m, 5.5 ft 
• Ib) 1st    3.8 N • m (0.38 kgf 
• m, 2.7 ft 
• Ib)
1.8 N •
 m (0.18 kgf • m, 1.3 ft • Ib)
5 × 14 mm
2.5 N •
 m (0.25 kgf • m, 1.8 ft • Ib)
5 × 14 mm
3.4 N •
 m (0.34 kgf • m, 2.5 ft • Ib)
5 × 14 mm
8 × 16 mm
2nd   39 N • m (3.9 kgf 
• m, 28 ft 
• Ib) 1st    15 N • m (1.5 kgf 
• m, 11 ft 
• Ib)
8 × 16 mm
2nd   39 N • m (3.9 kgf 
• m, 28 ft 
• Ib) 1st    15 N • m (1.5 kgf 
• m, 11 ft 
• Ib)
9
LT
572
LT 
						

							4-13
EFUELFUEL INJECTION SYSTEM
EXPLODED DIAGRAM
REMOVAL AND INSTALLATION CHART
Step Procedure/Part name Q’ty Service points
THROTTLE BODY 
DISASSEMBLYFollow the left “Step” for disassembly.
1 Screw/washer 3/3
2 Spacer 3
3 Fuel rail 1
4 Intake vacuum hose 3
5 Joint 1
6Injector 4
7 Grommet 4
8Screw 2
9 Intake air pressure sensor 1
10 Nut 1
17
8
9
1 10
12
13
11 3
16 151421218
23
22 21
23
24
25
26
27
28
29303120
19
454 763.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 7 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 50 mm
3.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 15 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 9 mm
2.0 N •
 m (0.2 kgf • m, 1.4 ft • Ib)
4 × 12 mm5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 9 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 10 mm
15 N •
 m (1.5 kgf • m, 11 ft • Ib)
3.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 15 mm
Not reusable 
						

							4-14
EFUELFUEL INJECTION SYSTEM
EXPLODED DIAGRAM
Step Procedure/Part name Q’ty Service points
11 Intake air temperature sensor 1
12 Screw 1
13 Bracket 1 1
14 Screw 2
15 Fuel pipe 1
16 O-ring 1
17 Screw 2
18 Bracket 2 1
19 Screw 2
20 Throttle stop guide 1
21 Screw 2
22 Throttle stop screw bracket 1
17
8
9
1 10
12
13
11 3
16 151421218
23
22 21
23
24
25
26
27
28
29303120
19
454 763.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 7 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 50 mm
3.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 15 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 9 mm
2.0 N •
 m (0.2 kgf • m, 1.4 ft • Ib)
4 × 12 mm5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 9 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 10 mm
15 N •
 m (1.5 kgf • m, 11 ft • Ib)
3.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 15 mm
Not reusable 
						

							4-15
EFUELFUEL INJECTION SYSTEM
EXPLODED DIAGRAM
Step Procedure/Part name Q’ty Service points
23 Screw/spring 4/4
24 Bypass air screw 4
25 Spring 4
26 Washer 4
27 O-ring 4
28 Screw 2
29 Throttle position sensor 1
30 O-ring 1
31 Throttle bodies 1
Reverse the disassembly steps for 
assembly.
17
8
9
1 10
12
13
11 3
16 151421218
23
22 21
23
24
25
26
27
28
29303120
19
454 763.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 7 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 50 mm
3.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 15 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 9 mm
2.0 N •
 m (0.2 kgf • m, 1.4 ft • Ib)
4 × 12 mm5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 9 mm
5.0 N •
 m (0.5 kgf • m, 3.6 ft • Ib)
6 × 10 mm
15 N •
 m (1.5 kgf • m, 11 ft • Ib)
3.5 N •
 m (0.35 kgf • m, 2.5 ft • Ib)
5 × 15 mm
Not reusable
Not reusable 
						

							4-16
EFUELFUEL INJECTION SYSTEM
SERVICE POINTS
Hose clamps removal
1. Remove:
Hose clamps
CAUTION:
If the hose clamps are removed without
cutting the joint first, the fuel hose will be
damaged.
Hose clamps installation
1. Install:
Hose clamps
 WARNING
Do not reuse the hose clamps, always
replace them with new ones.
NOTE:
Crimp the hose clamps properly to securely
fasten them.
Fuel hose disconnection
 WARNING
Before disconnecting the hose, remove the
fuel tank filler cap to reduce any pressure
inside the fuel tank, and then disconnect
the battery negative lead to cut off the elec-
tric current to the electrical systems.
1. Wrap the quick connector with a cloth, and
then rotate the quick connector tab 1
 to
the stopper position a
.
 WARNING
If the quick connector is removed sud-
denly, pressurized fuel could spray out. To
gradually release the fuel pressure, be sure
to remove the quick connector slowly.
1
2
a 
						

							4-17
EFUEL
CAUTION:
Do not rotate the quick connector tab 
1
past the stopper position 
a, otherwise it
could be damaged.
When the fuel hoses are disconnected,
quickly remove the retainer 
2 from the
quick connector, otherwise the retainer
could be lost.
2. Disconnect the fuel hose 1
 from the fuel
pipe 2
 directly.
 WARNING
Always reduce the fuel pressure in the fuel
line before servicing the line or the fuel
pipe. If the fuel pressure is not released,
pressurized fuel could spray out.
1
2
3. Cover the quick connector and fuel pipe
with a plastic bag to prevent damage and
to protect them from dirt.
Fuel line inspection
1. Inspect:
Fuel hose
Damage/cracks →
 Replace.
O-rings (quick connector)
Damage/cracks →
 Replace the quick
connector.
Fuel pipe
Damage/cracks →
 Replace the fuel
pump.
FUEL INJECTION SYSTEM 
						

							4-18
EFUELFUEL INJECTION SYSTEM
Fuel hose installation (replacing with new 
fuel hose)
1. Install:
Fuel hose 1
 
NOTE:
To install the fuel hose, be sure to align the
white mark a
 of the fuel hose with the
checker tab 2
 of the quick connector.
When replacing the fuel hose with a new
one, a checker tab 2
 that has half engage-
ment prevention is attached to the quick con-
nector of the hose. If the quick connector is
completely installed to the fuel pipe, it is
removable.
2
1a
2
Fuel hose connection
1. Apply a thin coat of engine oil to the con-
tact surfaces of the fuel pipe.
2. Insert the quick connector into the fuel
pipe until you hear a “click.”
3. To check the connection of the quick con-
nector, push and pull on the quick connec-
tor several times until there is free play of
2–3 mm (0.08–0.12 in).
NOTE:
If free is not obtained, disconnect the fuel hose
and check the O-ring for damage and that it is
properly installed.
Throttle body removal
1. Remove:
Throttle body
CAUTION:
Do not bend the fuel pipe 
1.
1 
						

							4-19
EFUELFUEL INJECTION SYSTEM
Fuel injector inspection
CAUTION:
The throttle bodies should not be disas-
sembled unnecessarily.
1. Check:
Injector
Dirt/residue →
 Clean.
Damage →
 Replace.
2. Measure:
Fuel injectors resistance
Out of specification →
 Replace.
3. Check the operation of the fuel injector
using the “Stationary Test” of the Yamaha
Diagnostic System.
Digital circuit tester:
YU-34899-A/90890-03174
Fuel injector resistance:
14.0–15.0 
Ω at 20 °C (68 °F)
Throttle body inspection
1. Check:
Throttle body
Cracks/damage →
 Replace the throttle
bodies. 
						

							4-20
EFUELFUEL INJECTION SYSTEM
2. Check:
Fuel passages
Obstruction →
 Clean.
Checking steps:
Wash the throttle body in a petroleum
based solvent.
Do not use any caustic carburetor clean-
ing solution.
Blow out all of passages with com-
pressed air.
Throttle body installation
1. Install:
Throttle body
CAUTION:
Do not bend the fuel pipe 
1.
1
2. Install:
Fuel hose 1
 (throttle body side)
Clamp
NOTE:
Install the fuel hose with the white mark a fac-
ing up.
1 a
3. Adjust:
Throttle lever free play
Refer to “CONTROL SYSTEM” in Chap-
ter 3. 
						

							4-21
EFUELFUEL INJECTION SYSTEM
Throttle bodies synchronization
1. Remove:
Throttle bodies
Air filter case
2. Adjust:
Throttle bodies synchronization
Adjustment steps:
NOTE:
The bypass air screw 1
 should not be
adjusted. However, if it is necessary to
remove the bypass air screw, be sure to
note the number of times the screw is
turned from its set position. When installing
the screw, be sure to tighten the screw the
same number of turns as noted at removal.
If the number of turns is not known, turn the
screw approximately 2.5 times counter-
clockwise from the fully closed position.
CAUTION:
Do not start the engine when removing
the fuel hose. Fuel can spurt out when
the fuel pump is operated.
a. Loosen the throttle stop screw 2
 and
synchronizing screws #1 3
, #2 4
, and
#3 5
 until released from the levers.
NOTE:
Only butterfly valve #2 should be fully
closed and the other valves should be
halfway closed.
Check the valve for light leaks with a
flashlight. If there are no light leaks, the
valve is fully closed.
b. Turn synchronizing screw #2 4
 clock-
wise approximately 7 times until it starts
to contact the lever.
NOTE:
Butterfly valves #2 and #3 should be fully
closed. Butterfly valve #2 opens if the
screw is turned more than 7 times.
If butterfly valves #2 and #3 are not fully
closed, close the valves by adjusting syn-
chronizing screw #2 4
.