General; Disassembly - BRP BOMBARDIER DS250 2006 Shop Manual

Section 03 ENGINE
Subsection 09 (PISTON AND CYLINDER)

GENERAL

When diagnosing an engine problem, always per-
form an engine leak test. This will help pinpoint a
problem. Refer to the instructions included with
your leak tester and ENGINE LEAK TEST section
for procedures.
Always place the vehicle on level surface.
Always disconnect the negative wire from the bat-
tery before working the engine.
During assembly/installation, use the torque val-
ues and service products as in the exploded
views.
WARNING
Torque wrench tightening specifications
must strictly be adhered to.
Locking devices (ex.: locking tabs, elastic
stop nuts, self-locking fasteners, cotter pin,
etc.) must be installed or replaced with new
ones where specified. If the efficiency of
a locking device is impaired, it must be re-
newed.
When disassembling parts that are duplicated in
the engine, (valves, springs, etc.), it is strongly
recommended to note their position and to keep
the parts of the same assembly as a "group". If
you find a defective component, it will be much
easier to find the cause of the failure among its
group of parts (for example, if you found a worn
valve guide, a bent spring could be the cause; it
will be easy to know which one of the springs is
the cause and to replace it). Besides, since parts
are matched together, it is a good practice to rein-
stall parts in the same position.
Intake port/air filter contaminated (clogged) with
dirt, sand, etc. (leads to worn valves, piston rings
and finally to leak of power).
CAUTION: In case of piston rings and/or valve
replacement, always clean the whole engine
and change oil.

DISASSEMBLY

Remove engine from vehicle. Refer to ENGINE
REMOVAL AND INSTALLATION.
Remove cylinder head.
HEAD.
Remove coolant hose then cylinder.
84
Refer to CYLINDER
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Remove cover crankcase opening with a clean
cloth.
Remove piston pin circlips.
WARNING
Piston ring circlips are spring loaded.
Discard circlips.
Push piston pin out and remove piston.
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Clean piston pin from deposits using synthetic
abrasive woven.
Remove gasket and dowel pins.
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