Sea-doo Rotax 1503 4-Tec 2005 User manual

C M Y CM MY CY CMY K
www.SeaDooManuals.net

2005
Engine Shop Manual
ROTAX®1503 4-TEC
ENGINES
www.SeaDooManuals.net

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
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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
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Section 01 ENGINES (1503 4-TEC)
Subsection 01 (LEAK TEST)
LEAK TEST
SERVICE TOOLS
Description Part Number Page
Drive shaft adapter ............................................................... 529 035 892 ............................................. 2
Drive shaft adapter ............................................................... 529 035 985 ............................................. 2
SERVICE PRODUCTS
Description Part Number Page
Molykote 111........................................................................ 413 707 000 ............................................. 4
PROCEDURES
PREPARATION
Theprocedurehastobedonewhenengineop-
erating temperature of approx. 70°C(158°F) is
reached.
WARNING
Prevent burning yourself due to handling on
the hot engine.
Remove:
–any parts to have access to engine
–safety lanyard
WARNING
Safety lanyard must be removed to prevent
engine to be cranked while fuel rail is re-
moved to prevent fuel to be sprayed out.
Fuel is flammable.
–jet pump (refer to JET PUMP in the appropriate
VEHICLE SHOP MANUAL)
–coolant tank cap
WARNING
To prevent burning yourself only remove the
coolant tank cap by wearing the appropriate
safety equipment.
–oil dipstick
1
R1503motr153A
1. Oil dipstick
–Unplug ignition coil and pull it out
–spark plug.
NOTE: Ignition coil may be used as an extractor.
SMR2005-032 1
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Section 01 ENGINES (1503 4-TEC)
Subsection 01 (LEAK TEST)
1
R1503motr154A
2
1. Ignition coil
2. Spark plug
–Remove valve cover cowl.
–Unscrew and remove valve cover.
2
R1503motr155A
1
1. Valve cover
2. Valve cover screw
PROCEDURE
The following procedure has to be performed for
each cylinder separately.
With an appropriate wrench lever, engine is rotat-
ed using the drive shaft adapter. Refer to the fol-
lowing table.
ENGINE TOOL
1503 4-TEC
Naturally Aspirated
1503 4-TEC
Supercharged
Drive shaft adapter
(P/N 529 035 892)
1503 4-TEC
Supercharged
Intercooled
Drive shaft adapter
(P/N 529 035 985)
529035892
DRIVE SHAFT ADAPTER
Rotate engine counterclockwise until the cylinder
no. 1 is at Top Dead Center (TDC) compression
stroke.
NOTE: Cylinder numbers are molded on valve cov-
er.
As the engine is turned over, observe the move-
ment of intake rocker arm of the cylinder to be
checked. After it completes the cycle and the in-
take valve closes, observe the piston. When it
reaches its uppermost position that is TDC com-
pression stroke.
2SMR2005-032
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Section 01 ENGINES (1503 4-TEC)
Subsection 01 (LEAK TEST)
1
R1503motr15 A
1. Intake rocker arms
Protect the hull area then position the wrench
lever so that it rest against hull to prevent further
crankshaft rotation.
Install gauge adapter into previously cleaned spark
plug hole.
Connect to adequate air supply.
NOTE: Each tester will have specific instruction
on the gauge operation and required pressure.
Set needle of measuring gauge to zero.
Supply combustion chamber with air.
1
R1503motr157A
2
3
1. Measuring gauge
2. Adequate adapter for spark plug hole
3. Air supply
Note the amount of leaking or percentage (de-
pending on tester).
LEAKAGE
PERCENTAGE
ENGINE
CONDITION
0% to 15% Excellent condition.
16% to 25% Good condition
26% to 40%
Fair condition; engine will run
and performance might be
down in some cases.
41% and higher Poor condition, diagnose and
repair engine.
Proceed the same way with remaining cylinders.
DIAGNOSIS
Pressurize area to be tested, spray soap/water so-
lution at the indicated location and look and/or lis-
ten for air bubbles.
–air escaping on intake port means leaking intake
valve(s)
–air escaping on exhaust port means leaking ex-
haust valve(s)
–air bubbles out of coolant tank means leaking
cylinder head gasket
–air escaping into crankcase area means exces-
sively worn and/or broken piston rings.
POSSIBLE ENGINE LEAKAGE
AREA
Spray soap/water solution at the indicated location
and look and/or listen for air bubbles.
Paying attention to the following checkpoints:
–clamp(s) tightened
–coolant hoses
–air/oil escaping from crankcase means dam-
aged gasket(s) and/or loosened screws (refer
to ENGINE BLOCK)
–air/water escaping from cylinder/head means
damaged gasket(s) and/or loosened screws (re-
fer to CYLINDER HEAD)
–oilycontaminationonweephole(speedsen-
sor area) means a damaged oil seal on coolant
pump shaft
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Section 01 ENGINES (1503 4-TEC)
Subsection 01 (LEAK TEST)
–coolant escaping from weep hole means a dam-
aged rotary seal on coolant pump shaft (refer to
COOLING SYSTEM)
1
R1503motr158A
1. Weep hole
–coolant escaping from coolant pump housing
means damaged gasket(s) and/or loosened
screws (refer to COOLING SYSTEM).
NOTE: For all the checkpoints mentioned above
see the appropriate engine section to diagnose
and repair the engine.
ASSEMBLY
NOTE: For assembly, use the torque values and
Loctite products from the exploded views (refer
to proper engine section).
For assembly, reverse the preparation procedure.
NOTE: Prior to inserting the ignition coil in its lo-
cation, apply some Molykote 111 (P/N 413 707
000) around the seal area that touches the spark
plug hole. After installation, ensure the seal seats
properly with the engine top surface.
4SMR2005-032
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Section 01 ENGINES (1503 4-TEC)
Subsection 02 (INTAKE MANIFOLD AND SUPERCHARGER)
INTAKE MANIFOLD AND
SUPERCHARGER
SERVICE TOOLS
Description Part Number Page
4-pin socket .......................................................................... 529 035 948 ..................................... 20, 23
camshaft locking tool............................................................ 529 035 839 ........................................... 11
leak test pump...................................................................... 529 021 800 ........................................... 10
retaining key ......................................................................... 529 035 949 ............................... 18–19, 25
support plate......................................................................... 529 035 947 ..................................... 22–23
support/pusher .................................................................... 529 035 950 ........................................... 23
support/pusher ..................................................................... 529 035 950 ........................................... 22
Torx adapter.......................................................................... 529 035 938 ..................................... 17, 27
SERVICE PRODUCTS
Description Part Number Page
Kluber Isoflex grease ............................................................ 293 550 021 ........................................... 24
Loctite 243............................................................................ 293 800 060 ..................................... 23–27
Loctite 5910.......................................................................... 293 800 081 ........................................... 25
Super Lube grease ............................................................... 293 550 030 ........................................... 27
SMR2005-033 5
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Section 01 ENGINES (1503 4-TEC)
Subsection 02 (INTAKE MANIFOLD AND SUPERCHARGER)
Naturally Aspirated Engine — Intake Manifold and Throttle Body
10 Nm
(89 lbf
in )
Loctite 243
10 Nm
(89 lbf
in )
Nm
(53 lbf in )
10 Nm
(89 lbf
in )
Nm
(53 lbf in )
18 Nm
(159 lbf in )
10 Nm
(89 lbf in )
Loctite 243
Loctite 243
Oil
Loctite 243
Oil
smr2005-033-200_aen
TYPICAL
6SMR2005-033
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Section 01 ENGINES (1503 4-TEC)
Subsection 02 (INTAKE MANIFOLD AND SUPERCHARGER)
Supercharged Engine —Intake Manifold and Throttle Body
10 Nm
(89 lbfin)
Loctite 243
Oil
Loctite 243
Nm
(53 lbfin)
18 Nm
(159 lbfin)
Loctite 243
Nm
(53 lbfin)
10 Nm
(89 lbfin)
10 Nm
(89 lbfin)
Oil
Loctite 243
Loctite 243
smr2005-033-201_aen
SMR2005-033 7
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Section 01 ENGINES (1503 4-TEC)
Subsection 02 (INTAKE MANIFOLD AND SUPERCHARGER)
Supercharged Intercooled Engine —Intake Manifold and Throttle Body
Loctite
243
10 Nm
(89 lbfin)
Loctite
243
Nm
(53 lbfin)
Oil
Oil
18 Nm
(159 lbfin)
Loctite 243
10 Nm
(89 lbfin)
Loctite 243
Nm
(53 lbfin)
Oil Loctite 243
smr2005-033-008_aen
8SMR2005-033
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Section 01 ENGINES (1503 4-TEC)
Subsection 02 (INTAKE MANIFOLD AND SUPERCHARGER)
Supercharged Engines —Supercharger
R1503motr357S
30 Nm
(22 lbfft) Loctite 5910
30 Nm
(22 lbfft)
30 Nm
(22 lbfft)
10 Nm
(89 lbfin)
Loctite 243
Anti-seize
lubricant
Oil
Klueber isoflex
30 Nm
(22 lbfft)
Oil
Loctite 243
Loctite 243
Loctite 243
SMR2005-033 9
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Section 01 ENGINES (1503 4-TEC)
Subsection 02 (INTAKE MANIFOLD AND SUPERCHARGER)
INSPECTION (PARTS
ASSEMBLED)
Intercooler Leak Test
Supercharged Intercooled Engine
Perform intercooler leak test when engine looses
performance, when there is white exhaust smoke
or when temperature in exhaust system is to high.
WARNING
Let engine cool down prior to perform leak
test. Direct contact with hot engine may re-
sult in skin burn.
NOTE: The inspection can be done while inter-
cooler remains installed in intake manifold.
Remove:
–outlet hose from exhaust manifold
–inlet hose from intercooler.
smr2005-033-007_a
1. Intercooler
2. Outlet hose
3. Inlet nipple
Plug intercooler inlet nipple.
Install an adapter on the outlet hose to connect
the leak test pump (P/N 529 021 800).
529 021 800
Pressurize the intercooler as follows:
PRESSURE TEST
69 kPa (10 PSI) for 10 minutes min
If there is a pressure drop, first spray hoses and
adapters with a soapy solution to ensure they are
not leaking.
Otherwise, remove intercooler from manifold to
spray soapy water on it. If air bubbles are present,
replace the intercooler. Refer to procedures far-
ther in this section.
Properly reinstall removed parts.
The distance between engine block and intercool-
er outlet hose must be 3 - 7 mm (0.12 - 0.27 in) oth-
erwise the hose would scuff on the engine block.
1
R1503motr3 4A
A
1. Outlet hose distance
A. 3-7mm(0.12 - 0.27 in)
10 SMR2005-033
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