Arctic Cat 650 Twin2004, Service Manual

Page: 52 / 210

3-23
3
ATV-1085C

NOTE: Note the direction of the front (F) of the
piston (5) for correct ring end gap orientation.
2. Install the compression rings (1 and 2) so the letter
on the top surface of each ring faces the dome of
the piston. Rotate the rings until the ring end gaps
are on directly opposite sides of the piston (see
illustration).
726-306A
CYLINDER/CYLINDER HEAD
ASSEMBLY

NOTE: If the cylinder/cylinder head assembly
cannot be trued, they must be replaced.
Cleaning/Inspecting Cylinder Head
1. Using a non-metallic carbon removal tool, remove
any carbon buildup from the combustion chamber
being careful not to nick, scrape, or damage the
combustion chamber or the sealing surface.
2. Inspect the spark plug hole for any damaged
threads. Repair damaged threads using a
“heli-coil” insert.
3. Place the cylinder head on the surface plate
covered with #400 grit wet-or-dry sandpaper.
Using light pressure, move the cylinder head in a
figure eight motion. Inspect the sealing surface for
any indication of high spots. A high spot can be
noted by a bright metallic finish. Correct any high
spots before assembly by continuing to move the
cylinder head in a figure eight motion until a
uniform bright metallic finish is attained.
CC128D
Measuring Cylinder Head
Distortion
1. Remove any carbon buildup in the combustion
chamber.
2. Lay a straightedge across the cylinder head; then
using a feeler gauge, check the distortion factor
between the head and the straightedge.
3. Maximum distortion must not exceed
specifications.
CC141D
Cleaning/Inspecting Cylinder
1. Wash the cylinder in parts-cleaning solvent.
! CAUTION
Incorrect installation of the piston rings will
result in engine damage.
! CAUTION
The cylinder head studs must be removed for
this procedure.
! CAUTION
Water or parts-cleaning solvent must be used in
conjunction with the wet-or-dry sandpaper or
damage to the sealing surface may result.