Technical data

Section 04 ENGINE
Sub-Section 02 (TOP END)
040-02-3
ENGINE DESCRIPTION
587, 717 and 787 Engines
The 2-stroke ROTAX engine rotates counterclock-
wise seen from the rear (PTO flywheel). It has a
rotary valve to control opening and closing of in-
take. Lubrication is provided by a variable rate oil
injection pump. It is cooled by water supplied
from the jet pump. It has a NIPPONDENSO Ca-
pacitor Discharge Ignition System. The fuel is pro-
vided by diaphragm MIKUNI carburetor(s) having
an integrated fuel pump.
CAUTION : No engine components can be
interchanged between engines.
787 Engine Only
This engine is canted at a 30 degree angle, lower-
ing the center of gravity of the watercraft. Cylin-
der exhaust ports are located on the same side of
the intake, allowing a new high volume tuned pipe
design. This engine also features the RAVE sys-
tem (Rotax Adjustable Variable Exhaust). The
RAVE system working in combination with the
high volume tuned pipe offers a broader power
band.
GENERAL
When repairing a seized engine, connecting rods
should be checked for straightness and crank-
shaft for deflection / misalignment. Refer to EN-
GINE 04-03 for procedures.
DISASSEMBLY
In order to repair engine top end proceed as fol-
lows :
Electrical Connections
Disconnect thermosensor wire and spark plug ca-
bles.
Connect spark plug cables on grounding device.
Exhaust System
To withdraw tuned pipe, refer to ENGINE 04-05.
Air Intake Silencer
To remove air intake silencer, refer to FUEL SYS-
TEM 06-02.
1,2, Cylinder Head Cover and Cylinder
Head
Remove cylinder head cover.
NOTE : With the 717 and 787 engines, cyl-
inder head screws secure also cylinder head
cover.
If shells, sand, salt or any other particles are
present in cylinder head, clean with a vacuum
cleaner.
Remove cylinder head.
If shells, sand, salt water or any other particles are
present in cylinder cooling jacket, clean with a
vacuum cleaner.
Remove cylinders, being careful that connecting
rods do not hit crankcase edge.
WARNING : If screws need to be heated
for removal when engine is in watercraft,
fuel system pressurization must be done first.
Do not use open flame ; use a heat gun.
NOTE : Even if only one cylinder needs re-
pair, both cylinders should be lifted to allow
1-piece cylinder base gasket replacement.
3,4,5,6, Piston, Piston Pin, Circlip and
Roller Bearing
NOTE : The 717 and 787 engines feature
cageless piston pin bearing.
Bring piston to Top Dead Center and install rubber
pad (P / N 295 000 101) over crankcase opening.
Secure with screws. Lower piston until it sits on
pad.
1. Rubber pad
-
;
F01B0JA
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