Yamaha SUPER JET SJ650Q 1991 User manual

PROTECT YOUR INVESTMENT
Use Genuine YAMAHA Parts And Accessories
LIT-18616-00-77
Service Manual
SUPER JET
SJ650Q
LIT-18616-00-77
Service Manual
YAMAHA MOTOR CORPORATION, U.S.A.
PRINTED IN U.S.A.
SJ650Q
18616-00-77 CVR_R 8/16/05 8:52 PM Page 1

~
) .YAMAHA
) .
) SUPER
JET
SJ650Q

A20000-1
NOTICE
This manual has been prepared by the Yamaha Motor Corporation,
U.S.A.
primarily for use
by Yamaha dealers and theirtrained mechanics when performing maintenance procedures
and repairs to Yamaha equipment. It has been written to suit the needs
of
persons who have
a basic understanding
of
the mechanical and electrical concepts and procedures inherent
in the work, for without such knowledge attempted repairs or service to the equipment could
render it unsafe or unfit for use.
Because the Yamaha Motor Corporation,
U.S.A.
has a policy
of
continuously improving its
products, models may differ in detail from the descriptions and illustrations given in this
publication. Use only the latest edition
of
this manual. Authorized Yamaha dealers are
notified periodically
of
modifications and significant changes in specifications and pro-
cedures, and these are incorporated in successive editions
of
this manual.
A10001-1"
SUPER
JET
(SJ650Q)
SERVICE MANUAL
©
1991
Yamaha Motor Corporation, U.S.A.
1st Edition, September
1991
All rights reserved.
No part
of
this publication may
be
reproduced
or transmitted in any form
or
by any means
including photocopying and recording without
the written permission
of
the copyright holder.
Such written permission must also be obtained
before any part
of
this
publication is stored
in a retrieval system
of
any nature.
Printed in Japan
P/N
LIT-18616-00·77

A507IJO.O
HOW TO USE THIS MANUAL
MANUAL FORMAT
All
of the procedures in this manual are organized in a sequential, step-by-step format. The
information has been complied to provide the mechanic with
an easy to read, handy refe-
rence that contains comprehensive explanations of all disassembly, repair, assembly, and
inspection operations.
In this revised format, the condition of a faulty component will precede an arrow symbol and
the course
of action required will follow the symbol, e.g.,
• Bearings
Pitting/Damage
..... Replace.
To assist you to find your way about this manual, the Section Title and Major Heading is
given at the head
of every page.
An Index to contents is provided on the first page of each Section.
THE ILLUSTRATIONS
Some illustrations in this manual may differ from the model you
have. This is because a
procedure described may relate to several models, though only one may
be illustrated. (The
name of model described will be mentioned in the description).
REFERENCES
These have been kept to a minimum; however, when you are referred to another section of
the manual, you are told the page number to go to.
WARNINGS, CAUTIONS
AND NOTES
Attention is drawn to the various Warnings, Cautions and Notes which distinguish impor-
tant information in this manual in the following ways.
~The'Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR SAFETY IS IN-
VOLVED!
A WARNING
Failure to follow WARNING instructions could result in severe injury or death to the water
vehicle operator, a bystander, or a peason inspecting or repairing the water vehicle.
;lttiiRIII!I;I __________________________ _
A CAUTION indicates special precautions that must be taken to avoid damage to the water
vehicle.
NOTE:----------------------------------------------------
A NOTE provides key information to make procedures easier or clearer.

HOW TO READ DESCRIPTIONS
1. An easy-to-see disassembly illustration is mainly provided for a disassembly job.
2. Numbers are given in the order of a disassembly job in the disassembly illustration.
3. An explanation of jobs and notes is presented in an easy-to-read way by the use of
symbol marks. The meanings
of the symbol marks are given on the next page.
4. A job instruction chart accompanies the assembly illustration, providing the order of
jobs, names
of parts, notes in jobs, etc.
5.1n addition to the disassembly illustration, "REMOVAL POINTS" is provided to supple-
ment
in detail the explanation which does or cannot necessarily cover the main jobs.
6. Jobs necessary before and afterthosewhich are not included in the disassembly illustra-
tion are explained before the same illustration as related jobs.
CD Section
® Preparation for removal
@ Order of removal
@)Part name
@O'ty
__.ID
I 1.1
REED VALVE, CYLINDER HEAD, CYLINDER
. POWR. . AND PISTON
REED VALVE, CYLINDER HEAD, CYLINDER AND PISTON
PREPARA110N FOR REMOVAL
J
~§;;;.~;:.
• RernowetM cartlureiOf.
2
®Remarks
0 Removal point
® Extent of removal
®Symbol mark
@ Exploded diagram
I ,., REED VALVE, CYLINDER HEAD, CYLINDER
POWR AND PISTON
N01I ON REMOVAL REASSEMBLY
•With the engine mounted, tht following pans can be removed.
•BeloreS«Vic:ing.cteanti'HtpartJ. and takecareaotl'lat foreign maltlrlal do not .mer the
...........
•RM!ove the gutcet adhclnld on the contec:Ung surtKe.
•Take care not to scratch the contacttng surface when removing the cyfinderand cylinder
.....
•Take care not no $CfKtCtt the cyllndel' and pleton surface.
•For I'UIMiftbly, the removed parts should be c:leanecl with solvent, and appty the two-
cycle OUlboafd oil cmto the sliding surface.
®<
Extent ol removal: @Reed valVe ntniO\'al ® Cylinder head removal
®Cylinder removal ® Piston and I»Ston ring removal
Extent ol rei!IO'Ial Order Part name Q'ty Remarks
2 lntakemanllofd
1 Bolt s 1
! =p 14'
5 Clomp~ ................
6 Exhaust no.
7 Clamp
8 Clamp
9 Boll
10 Mulllef, 2
11 Boll
12 Muffter.t
13 Bolt
14 Cyllnderheacl
15 Bolt
16 Cylinder
17 Clip
18 Piston pin
,. ,_
20 IStnall end bearing
21 Pi$ton ring
Loosen the screw.
Loosen the sorew.

CD
1~~~~1
•
·I
@
l~8~ltitl
®
IPOWRI•I
(j)
J
ELEcJUJ
®
IJ~~~I
? I
•
®
~
@
1~1
@
[ij]
@
~
@
~
®
l
a·
572
@
~
@
I
SPEC
I
o-1
@
I
FUEL
I
_i)
I
®
I
JET I
rl
:PUMP:-
--:
®
1~85~1
•I I
@
~
®
[g]
@
~
@ 1
m
@
~
®
a
a
242
@
l
a
A50000·IJ.4
SYMBOLS
Symbols
CD
to
® are designed as thumb-
tabs to indicate the content
of
a chapter:
CD
General Information
@
Specification
@
Inspection and adjustment
@ Fuel System
®Power
Unit
®
Jet
Pump
Unit
(j)
Electrical System
® Hull and Hood
®Trouble-shooting
Symbols
@
to
@
indicate specific data:
@
Special tool
®Lubricant
® Engine speed
@Tightening torque
@ Specified value, Service limit
@ Resistance
(!J),
Voltage
(V),
Electric current
(A)
Symbol @ to
@
in
an
exploded diagram
indicate grade
of
lubricant and location
of
lubrication point:
@Apply
Yamaha two-cycle outboard oil
(Yamalube two-cycle outboard oil,
Yamalube
1)
@ Apply water registance grease
(Yamaha grease
A,
Yamaha marine
grease)
@ Apply water registance grease
(Yamaha grease
D,
Yamaha marine
grease)
Symbols @ to @ in an exploded diagram
indicate grade
of
sealing or locking agent,
and location
of
application point:
@ Apply Gasket maker
@)
Apply LOCTITE No.
242
(Blue
LOCTITE)
@ Apply LOCTITE No.
572
@Apply
Silicone sealant
@Apply
Yamabond
#
(Yamaha bond
No.4)
NOTE:-----------
In this manual, the above symbols may not
be used
in
every case.

ELECTRICAL SYSTEM
HULL AND HOOD
TROUBLE-SHOOTING
ELEC
•
HULL
HOOD
?
•
TRBL
SHTG

CHAPTER
1.
GENERAL INFORMATION
IDENTIFICATION NUMBERS ..........................................................................
1-1
PRIMARY I.D. NUMBER .............................................................................
1-1
ENGINE SERIAL NUMBER ........................................................................
1-1
PUMP SERIAL NUMBER ...........................................................................
1-1
HULL
IDENTIFICATION NUMBER (H.I.N.) ...............................................
1-1
DIMENSIONS ....................................................................................................
1-2
SAFETY
WHILE
WORKING .............................................................................
1-3
FIRE PREVENTION ....................................................................................
1-3
VENTILATION .............................................................................................
1-3
SELF-PROTECTION ....................................................................................
1-3
OILS, GREASES AND SEALING FLUIDS ................................................
1-3
GOOD WORKING PRACTICES .................................................................
1-4
DISASSEMBLY AND ASSEMBLY .............................................................
1-4
SPECIAL TOOLS ...............................................................................................
1-5
FOR TUNE-UP .............................................................................................
1-5
FOR POWER UNIT SERVICE ....................................................................
1-6
FOR JET UNIT SERVICE ...........................................................................
1-7

IDENTIFICATION NUMBERS
MODEL._!
_
___,l
EW2._l
__
_,
1-1
IDENTIFICATION NUMBERS
PRIMARY I.D. NUMBER
The primary
1.0.
number is stamped
on
a
plate attached
to
the inside
of
the engine
compartment.
Starting Primary
J.D.
Number:
811701
-
ENGINE SERIAL NUMBER
The engine serial number is stamped
on
a
plate attached to the intake manifold.
Starting serial number:
016911
-
PUMP SERIAL NUMBER
The
jet
pump unit serial number is stamped
on a plate attached on the intermediate
housing.
Starting serial number:
517111
-
HULL IDENTIFICATION NUMBER (H.I.N.)
The H.I.N. is stamped on the rear end
of
the
footrest floor.

,.~~~
I •
·I
DIMENSIONS
A60750:0'
DIMENSIONS
1,525 mm (60.0 in)
90mm
(3.54
in)
660
mm
(26.0 in)
1-2
c:
-
N
(X)
~
E
E
0
"""
N
-
N
680
mm
(26
8 in)
~
~
~
~;,-
~~
__,?=
~~I
I
~~~

,.~~~
I
..
·I
SAFETY WHILE WORKING
A70000-1
SAFETY WHILE WORKING
The procedures given in this manual are those recommended by Yamaha to be followed
by Yamaha dealers and their mechanics.
FIRE PREVENTION
Petrol (petroleum spirit, gasoline) is highly flammable.
Petroleum vapour is explosive
if
ignited.
Do
not smoke while handling gasoline, and keep
it
away from heat, sparks, and open flames.
VENTILATION
Petroleum vapour is heavier than air and
if
inhaled in large quantities will not support life.
Engine exhaust gases are harmful
to
breathe. When test-running
an
engine indoors, main-
tain good ventilation.
SELF-PROTECTION
Protect your eyes with suitable safety spectacles or safety goggles when using compressed
air, when grinding
or
when doing any operation which may cause particles to fly off.
Pro-
tect hands and feet by wearing safety golves or protective shoes
if
appropriate to the work
you are doing.
OILS, GREASES AND SEALING FLUIDS
Use
only genuine Yamaha oils, greases and sealing fluids orthose recommended by Yamaha.
Under normal conditions
of
use, there should
be
no hazards from the use
of
the lubricants
mentioned in this manual, but safety is all-important, and by adopting good safety prac-
tises. any risk is minimised. A summary
of
the most important precautions is as follows:
1.
While working, maintain good standards
of
personal and industrial hygiene.
2.
Clothing which has become contaminated with lubricants should be changed as soon
as practicable, and laundered before further use.
3.
Avoid skin contact with lubricants; do not, for example, place a soiled wiping rag in
one's pocket.
4.
Hands, and any other part
of
the body which have been in contact with lubricants or
lubricant-contaminated clothing, should
be
thoroughly washed with hot water and soap
as soon as practicable.
5.
To protect the skin, the application
of
a suitable barrier cream
to
the hands before
working is recommended.
6.
A supply
of
clean lint-free cloths should
be
available for wiping purposes.
1-3

I~~~~
I •
·I
SAFETY WHILE WORKING
GOOD WORKING PRACTICES
1.
The right
tools
Use the special tools that
are
advised to protect parts from damage.
Use
the right tool
in the right
manner-don't
improvise.
2.
Tightening torque
Follow the torque tightening instructions.
When
tightening bolts, nuts and screws, tighten
the larger sizes first, and tighten inner-positioned fixings before outer-positioned ones.
3.
Non-reusable items
Always use new gaskets, packings, 0-rings, split-pins and circlips etc.
on
reassembly.
DISASSEMBLY AND ASSEMBLY
1.
Clean parts with compressed-air
on
disassembling them.
2.
Oil the contact surfaces
of
moving parts
on
assembly.
3.
After assembly, check that moving parts operate normally.
4.
Install bearings with the manufacturer's markings on the side exposed to view, and
liberally oil the bearings.
5.
When installing oil seals, apply a light coating
of
water-resistant grease to the outside
diameter.
1-4

SPECIAL TOOLS
YU-3097 90890-01252
y~~
~
~
YU-34899-A 90890-03112
YU-91022-B
1-5
A80701-0"
SPECIAL TOOLS
The use
of
correct special
tools
recommend-
ed by Yamaha
will
aid
the
work and enable
accurate assembly and tune-up. Improvisa-
tions and use
of
improper
tools
can
cause
damage
to
the equipment.
NOTE:------------
• For U.S.A. and Canada, use part
number
starting
with
"VB-",
"YU-"
or
"YW-".
• For others, use part
number
starting
with
"90890-".
FOR
TUNE-UP
1.
Dial gauge and
stand
P/N. YU-3097, YU-1256
90890-01252
2.
Pocket
tester
P/N. YU-34899-A
90890-03112
3.
CDI tester
P/N. YU-91022-B

SPECIAL TOOLS
YU-33223-1 90890-06751
YU-3017 90890-06759
YU-8036-A 90890-06760
YB-6117 90890-06521
&p
'~
,,
Ppp
"""
YB-6139 90890-06522
1-6
4.
Compression
gauge
P/N. YU-33223-1
90890-06751
5.
Cylinder
gauge
set
P/N. YU-3017
90890-06759
6.
Tachometer
P/N. YU-8036-A
90890-06760
FOR POWER UNIT SERVICE
1. Flywheel
puller
P/N.
YB-6117
90890-06521
2.
Flywheel
holder
P/N.
YB-6139
90890-06522

SPECIAL TOOLS
YU-35557 90890-06534
YW-38742 90890-06069
YW-38741 90890-06425
YB-6049
90890-06518
YB-6096
1-7
3.
Bearing separater
P/N.
YU-35557
90890-06534
FOR JET UNIT SERVICE
1.
Shaft holder
P/N.
YW-38742
90890..()6069
2.
Coupler wrench
P/N.
YW-38741
90890-06425
3.
Drive shaft holder
P/N.
YB-6049
90890-06518
4.
Slide hammer set
PIN.
YB-6096
90890-06523
90890-06531

YB-6071
YB-6229
YB-6016
YB-34474
YB-6156
SPECIAL TOOLS
90890-06606
90890-06626
90890-06662
90890-06634
1-8
5. Driver rod
PIN. YB-6071, YB-6229
90890-06606
6. Bearing outer race attachment
P/N. YB-6016
90890-06626
7. Bearing inner race attachment
P/N. YB-34474
90890-06662
8. Ball bearing attachment
P/N. YB-6156
90890-06634

I SPECI·.r I
------------------------------------------
C107CJO.O"
CHAPTER 2.
SPECIFICATIONS
GENERAL SPECIFICATIONS .......................................................................... 2-1
MAINTENANCE SPECIFICATIONS ................................................................ 2-2
1. Engine ......................................................................................................2-2
2. Electrical .................................................................................................. 2-4
TIGHTENING TORQUE .................................................................................... 2-5
GENERAL TORQUE SPECIFICATIONS ......................................................... 2-5
PIPE ROUTING DIAGRAM .............................................................................. 2-6
CABLE ROUTING DIAGRAM .......................................................................... 2-7

ISPEC I
rr--1
GENERAL SPECIFICATIONS
C2070IJ.O•
GENERAL
SPECIFICATIONS
Model code:
Hull
Engine
Dimensions:
Length
Width
Height
Dry
weight
Performance:
Maximum output
Maximum fuel consumption
Cruising range/at full throttle
Engine:
Engine type
Number
of
cylinder
Displacement
Bore & stroke
Compression ratio
Intake system
Carburetor type
Number
of
carburetor
Carburetor starting system
Scavenging system
Lubrication system
Cooling system
Starting system
Charging system
Ignition system
Ignition timing
Spark plug
Battery capacity
Lighting coil
Drive unit:
Propulsion system
Jet pump type
Impeller rotation
Transmission
Steering (nozzle) angle
Fuel and oil:
Fuel
Recommended engine oil
Gasoline
and
oil mixing ratio
Fuel tank capacity
I Unit
mm
(in)
mm
(in)
mm
(in)
kg
(lb)
EW2
6R7
SUPER
JET (SJ650Q)
2,240
(88.2)
680
(26.8)
660
(26.0)
130
(287)
kW (hp)/rpm
37.5
(50)/6000
l/h
(US
gal/h)
23
(6.1)
hr.
0.8
2-stroke
2
cc (cu.in)
633
(38.6)
mm
(in)
77
x
68
(3.03
x
2.68)
7.2
Reed
valve
Floatless type
1
Choke valve
Loop charged
Premix
Water-cooled
Electric starter
Flywheel magneto
C.D.I.
BTDC
15°-21°
NGK B8HS
V/kC
(A-h)
12/68.4
(19)
A/rpm
3±
1/5,500
Jet pump
Axial flow, single stage
Counter clockwise (Rear view)
Direct drive from engine
18.5°-24.5°
Unleaded regular gasoline
Yamalube two-cycle outboard oil
50:1
e
(US
gal)
18 (4.8)
Including 5.5 (1.45)
reserve
2-1

ISPECI ~I MAINTENANCE SPECIFICATIONS
MAINTENANCE SPECIFICATIONS
1. Engine
I~
Compression pressure:
Cylinder head:
Warp
limit
Cylinder:
Bore size
Taper
limit
Out of round limit
Piston:
Piston size
~
Measuring point*
Piston clearance ~· -1 1•
Wear limit / 1---1-•
Offset L
Piston ring:
Sectional sketch
End gap (Installed)
Side clearance
Crankshaft: D
(
®
T I
A' f-
Crank width "A" ..:..: C
Run out limit "B" A
Connecting rod big end side
clearance
"C"
Small end free play limit "D"
Unit SUPER JET (SJ650Q)
kPa (kg/cm2, psi) 940 (9.4, 134)
mm (in) 0.1 (0.0039)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
2-2
*Lines indicate. straightedge
measurement
77.00-77.02 (3.031-3.032)
0.08 (0.003)
0.05 (0.002)
76.915-76.940 (3.028- 3.029)
10 (0.39)
0.080-0.085 (0.031 - 0.0033)
0.1 (0.004)
1.0 (0.039), EX-side
Keystone
B=1.2
(0.047), T= 2.9 (0.114)
0.2- 0.4 (0.008- 0.016)
0.03- 0.05 (0.0012- 0.0020)
61.95-62.00 (2.439-2.441)
0.03 (0.0012)
0.3-0.7 (0.012-0.028)
2.0 (0.08)

I
SPECI
rr-1
MAINTENANCE SPECIFICATIONS
Unit
SUPER JET (SJ650Q)
m
Carburetor:
Stamped mark
6R701
Venturi bore
mm
(in)
<!>40
(1.57)
Main nozzle
mm
(in)
</>3.2
(0.126)
Main
jet
1 (M.J.
1)
mm
(in)
</>2.0
(0.079)
Main
jet
2 (M.J.
2)
# 115
Pilot
outlet
(P.O.)
mm
(in)
</>1.0
(0.03)
Pilot
jet
(P.J.) # 120
Bypass 1 (B.P.
1)
mm
(in)
</>0.6
(0.024)
Bypass 2 (B.P.
2)
mm
(in)
</>0.6
(0.024)
Bypass 3 (B.P.
3)
mm
~in)
</>0.9
(0.035)
Bypass 4 (B.P.
4)
mm
(in)
</>0.7
(0.028)
Low speed
screw
1-1/8±
114
Throttle valve (Th.V.) # 120
Valve seat (V.S.)
mm
(in)
</>
1.5
(0.059)
High speed
screw
1-3/8±
114
Return
jet
(RT
J)
mm
(in)
</>0.5
(0.02)
Trolling speed rpm
1,250±50
Reed valve:
~·
Thickness
mm
(in) *0.2 (0.008)
Valve
lift
mm
(in)
10.3-10.7
(0.406-0.421)
Bending
limit
mm
(in) 0.2 (0.008)
Jet
pump:
Impeller
clearan~
mm
(in)
0.2-0.6
(0.008-
0.024)
Service
limit
mm
(in) 0.6
(0.02)
Impeller
shaft
run
out
mm
(in) 0.5 (0.02)
2-3