Sea-doo Rotax 1503 4-Tec 2005 User manual

C M Y CM MY CY CMY K
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2005
Engine Shop Manual
ROTAX®1503 4-TEC
ENGINES
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Legal deposit:
National Library of Quebec
National Library of Canada 2005
All rights reserved. No parts of this manual may be reproduced in any form without the prior written
permission of Bombardier Recreational Products Inc. (BRP).
©Bombardier Recreational Products Inc. (BRP) 2005
Technical Publications
Bombardier Recreational Products Inc. (BRP)
Valcourt (Quebec) Canada
PrintedinCanada
®TMRegistered trademarks of Bombardier Recreational Products Inc. (BRP) or its affiliates.
* Trademark of Bombardier Inc. used under license.
SEA-DOO®
BOMBARDIER LUBE®
Sea-Doo Synthetic Grease
Sea-Doo®Learning KeyTM
DESSTM
Rotax®
TOPSTM
This document contains the trademarks of the following companies:
Loctite®is a trademark of Loctite Corporation
Snap-on®is a trademark of Snap-on Tools Corporation
Molykote©is a trademark of Dow Corning Corporation
AMP©is a trademark of Tyco Electronics Corporation
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TABLE OF CONTENTS
SAFETY NOTICE .................................................................................... III
INTRODUCTION ................................................................................... IV
GENERAL INFORMATION.......................................................................................... IV
ENGINE EMISSIONS INFORMATION ............................................................................ IV
ENGINE IDENTIFICATION NUMBER (E.I.N.) .................................................................... IV
TIGHTENING TORQUES ........................................................................................... IV
ARRANGEMENT OF THIS MANUAL, ILLUSTRATIONS AND PROCEDURES ............................. V
01 ENGINES (1503 4-TEC)
01 –LEAK TEST ...................................................................................................... 1
PROCEDURES .................................................................................................. 1
PREPARATION ........................................................................................................ 1
PROCEDURE .......................................................................................................... 2
DIAGNOSIS............................................................................................................ 3
POSSIBLE ENGINE LEAKAGE AREA................................................................................ 3
ASSEMBLY ............................................................................................................ 4
02 –INTAKE MANIFOLD AND SUPERCHARGER............................................................... 5
INSPECTION (PARTS ASSEMBLED). . . . .. . . . .. .. . .. .. . . . .. . .. .. . .. . . .. . .. .. . .. . . . .. .. . .. .. . . . .. .. . .. . . . .. .. . .. .. . . . 10
REMOVAL ............................................................................................................ 12
DISASSEMBLY ....................................................................................................... 17
INSPECTION (PARTS DISASSEMBLED) . . .. .. . . . .. .. . .. . . . .. .. . .. .. . . . .. .. . .. .. . . . .. . .. .. .. . . . .. . .. .. . .. . . . .. .. . .. 20
ASSEMBLY ........................................................................................................... 21
INSTALLATION ....................................................................................................... 26
03 –PTO HOUSING AND MAGNETO .......................................................................... 29
GENERAL...................................................................................................... 31
PROCEDURES ................................................................................................ 31
PTO HOUSING ....................................................................................................... 31
PTO SEAL............................................................................................................. 34
COUPLING............................................................................................................ 35
STATOR ............................................................................................................... 35
ROTOR AND TRIGGER WHEEL .................................................................................... 36
RING GEAR........................................................................................................... 37
STARTER DRIVE ASS'Y.............................................................................................. 38
OIL SPRAY NOZZLE ................................................................................................. 39
04 –LUBRICATION SYSTEM..................................................................................... 41
GENERAL...................................................................................................... 45
PROCEDURES ................................................................................................ 45
ENGINE OIL PRESSURE............................................................................................. 45
PTO OIL STRAINER.................................................................................................. 46
SUCTION PUMP OIL STRAINER.................................................................................... 47
ENGINE OIL PRESSURE REGULATOR............................................................................. 49
OIL PRESSURE PUMP............................................................................................... 51
OIL SUCTION PUMP................................................................................................. 54
OIL SEPARATOR COVER............................................................................................ 57
TOPS VALVE.......................................................................................................... 58
OIL COOLER ......................................................................................................... 58
05 –COOLING SYSTEM .......................................................................................... 61
GENERAL...................................................................................................... 63
PROCEDURES ................................................................................................ 63
COOLANT PUMP .................................................................................................... 63
COOLANT PUMP IMPELLER ....................................................................................... 64
I
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TABLE OF CONTENTS
THERMOSTAT........................................................................................................ 65
ROTARY SEAL........................................................................................................ 65
06 –CYLINDER HEAD ............................................................................................. 69
GENERAL...................................................................................................... 71
PROCEDURES ................................................................................................ 71
SPARK PLUG ......................................................................................................... 71
EXHAUST MANIFOLD............................................................................................... 71
VALVE COVER........................................................................................................ 72
ROCKER ARM........................................................................................................ 73
CAMSHAFT TIMING GEAR.......................................................................................... 76
TIMING CHAIN ....................................................................................................... 77
CYLINDER HEAD..................................................................................................... 78
CAMSHAFT........................................................................................................... 79
VALVE SPRING ....................................................................................................... 80
VALVE ................................................................................................................. 82
07 –CYLINDER BLOCK............................................................................................ 89
GENERAL...................................................................................................... 92
PROCEDURES ................................................................................................ 92
TIMING CHAIN ....................................................................................................... 92
CHAIN TENSIONER.................................................................................................. 92
PISTON/CONNECTING ROD........................................................................................ 93
PISTON RINGS ....................................................................................................... 98
CRANKSHAFT........................................................................................................ 99
BALANCER SHAFT................................................................................................. 104
CYLINDER BLOCK ................................................................................................. 107
08 –TECHNICAL SPECIFICATIONS ............................................................................ 113
II
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SAFETY NOTICE
SAFETY NOTICE
This manual has been prepared as a guide to correctly service and repair the Rotax®1503 4-TEC engines.
This edition was primarily published to be used by technicians who are already familiar with all service
procedures relating to BRP products. Mechanical technicians should attend training courses given by
BRP Training Dept.
Please note that the instructions will apply only if proper hand tools and special service tools are used.
This ENGINE SHOP MANUAL uses technical terms which may be slightly different from the ones used
in the PARTS CATALOG.
It is understood that this manual may be translated into another language. In the event of any discrepan-
cy, the English version shall prevail.
The content depicts parts and/or procedures applicable to the particular product at time of writing. Ser-
vice and Warranty Bulletins may be published to update the content of this manual. Make sure to read
and understand these.
In addition, the sole purpose of the illustrations throughout the manual, is to assist identification of the
general configuration of the parts. They are not to be interpreted as technical drawings or exact replicas
of the parts.
The use of BRP parts is most strongly recommended when considering replacement of any component.
Dealer and/or distributor assistance should be sought in case of doubt.
The engine identified in this document should not be utilized on product(s) other than those for which it
was designed.
WARNING
Unless otherwise specified, engine should be turned OFF and cold for all maintenance and repair
procedures.
This manual emphasizes particular information denoted by the wording and symbols:
WARNING
Identifies an instruction which, if not followed, could cause serious personal injury including pos-
sibility of death.
CAUTION: Denotes an instruction which, if not followed, could severely damage engine compo-
nents.
NOTE: Indicates supplementary information needed to fully complete an instruction.
Although the mere reading of such information does not eliminate the hazard, your understanding of the
information will promote its correct use. Always use common shop safety practice.
BRP disclaims liability for all damages and/or injuries resulting from the improper use of the contents.
We strongly recommend that any services be carried out and/or verified by a highly skilled professional
mechanic. It is understood that certain modifications may render use of the engine illegal under existing
federal, provincial and state regulations.
SMR2004-001 EN III
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INTRODUCTION
INTRODUCTION
GENERAL INFORMATION
This ENGINE SHOP MANUAL covers the Rotax
1503 4-TEC engine. It should be used in conjunc-
tion with the appropriate VEHICLE SHOP MANU-
AL.
The information and component/system descrip-
tions contained in this manual are correct at time
of writing. BRP however, maintains a policy of
continuous improvement of its products without
imposing upon itself any obligation to install them
on products previously manufactured.
BRP reserves the right at any time to discontinue
or change specifications, designs, features, mod-
els or equipment without incurring obligation.
This SHOP MANUAL uses technical terms which
may be different from the ones of the PARTS CAT-
ALOGS.
When ordering parts always refer to the specific
model PARTS CATALOGS.
ENGINE EMISSIONS
INFORMATION
Refer to the appropriate VEHICLE SHOP MANU-
AL.
ENGINE IDENTIFICATION
NUMBER (E.I.N.)
The Engine Identification Number is located on
front end of the engine.
F18D03A
1
1. Engine Identification Number (E.I.N.)
TIGHTENING TORQUES
Tighten fasteners to torque mentioned in explod-
ed views and/or text.
WARNING
Torque wrench tightening specifications
must strictly be adhered to. Locking devices
(ex.: locking tabs, elastic stop nuts, self-lock-
ing fasteners, etc.) must be installed or
replaced with new ones, where specified. If
the efficiency of a locking device is impaired,
it must be renewed.
IV
smr2005-002
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INTRODUCTION
ARRANGEMENT OF THIS
MANUAL, ILLUSTRATIONS
AND PROCEDURES
The manual is divided into many major sections as
you can see in the main table of contents at the
beginning of the manual.
Several sections are divided in various subsec-
tions. There is a table of contents at the beginning
of many sections.
The illustrations show the typical construction of
the different assemblies and, in all cases, may not
reproduce the full detail or exact shape of the parts
shown, however, they represent parts which have
the same or a similar function.
CAUTION: These watercraft are designed with
parts dimensioned mostly in the metric sys-
tem. However some components may be from
the imperial system. When replacing fasten-
ers, make sure to use only those recommended
by BRP.
As many of the procedures in this manual are inter-
related, we suggest, that before undertaking any
task, you read and thoroughly understand the en-
tire section or subsection in which the procedure
is contained.
A number of procedures throughout the book re-
quire the use of special tools. Before undertaking
any procedure, be sure that you have on hand all
the tools required, or approved equivalents.
smr2005-002 V
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INTRODUCTION
Subsection 04 (MAGNETO SYSTEM)
30
F01D4WS
Loctite
243
Loctite
243
Loctite
243
Loctite
243
Loctite
243
Loctite
48
145 Nm
(107 lbfft)
Anti-seize
lubricant
Page heading
indicates section
and subsection
detailed.
Exploded view
assists you in
identifying parts and
related positions.
TYPICAL PAGE
F01A0CT
Illustration number
for publishing
process.
Subsection title
indicates
beginning of the
subsection.
Dotted box
contains parts of
a particular
model or an
exploded view.
Page number
Italic sub-title
above exploded
view indicate
pertaining models.
Drop represents
a liquid product
to be applied to a
surface. In this case
octite 243 to
screw threads.
Bold face number
indicates special
procedure
concerning this part.
VI
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INTRODUCTION
1
2
Section 06 FUEL SYSTEM
Subsection 03 (CARBURETORS)
31
Diaphragm
XP Model Only
CARBURETOR REMOVAL
Inspect parts for corrosion dammage (shaft, butterfly,
spring screw, check valve housing, etc.).
PUMP DIAPHRAGM LEAK TEST
TYPICAL
To remove carburetors from engine, proceed as fol-
lows:
Remove air vent tube support.
Unlock retaining slides holding air intake silencer base.
Remove air intake silencer base from watercraft.
Remove screws holding flame arrester base support
to cylinder head cover.
Unscrew base retaining screws then remove base from
carburetors and move to front of watercraft.
Turn the valve to OFF position.
NOTE: For fuel line removal, use pliers (P/N 295
000 054).
Disconnect pulse line from fuel pump.
Disconnect fuel fuel supply line from fuel pump.
Disconnect fuel return line.
Disconnect oil injection pump cable, throttle cable and
choke cable.
Remove screws no. and lock washers no. 7 retaining
carburetors.
All Others Models
Remove 4 bolts no. 8 and lock washers no. 12 from
rotary valve cover then move carburetors and rotary
valve cover on top of engine.
NOTE: When removing rotary valve cover , pay
attention that the rotary valve stay in place, other-wise
it must be timed.
Remove carburetors from intake manifold.
Disconnect fuel bypass line between carburetors (twin
carburetors).
Remove carburetor(s) from rotary valve cover.
DISASSEMBLY AND INSPECTION
Using a suitable pump gauge tester, perform the fol-
lowing test proceeding as follows:
- Install pump gauge tester (P/N 295 000 083) on pulse
nipple.
- Pump tester until it reaches 28 kPa (4 PSI).
Diaphragm must stand pressure for 10 seconds. If
pressure drops, replace diaphragm.
F01F0XB
A
2
1
1 2
TYPICAL PAGE
Sub-title with part
name(s) from
exploded view.
TYPICA  mention
indicates a general
view which does not
represent full detail.
Sub-sub-title in this
case indicates that
particular procedure
for XP is finished, so
from this point, all
others models are
concerned.
Title in italic indicates a
particular procedure
concerning a model.
Service tool to be
used to perform a
certain procedure.
Title indicates main
procedure to be
carried-out.
Sub-sub-title in
capital indicates a
particular testing,
adjustment or
repair procedure.
Illustration
always follows
text it is
pertained to.
Numbered step are
used to give a
sequence to be
perfomed.
Numbers are used
for description of
components.
etters are used for
any measures.
Bold numbers in the
text refer to the parts
shown in the exploded
view at the beginning
of the subsection.
F01A0BT
smr2005-002 VII
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