KYMCO MXU400 - Page 48

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3. Place the cylinder head on the surface plate cov-
ered 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 cylin-
der head in a figure eight motion until a uniform
bright metallic finish is attained.
CC996
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.
2. Inspect the cylinder for pitting, scoring, scuffing,
warpage, and corrosion. If marks are found, repair
the surface using a cylinder hone (see Honing Cyl-
inder in this sub-section).
3. Place the cylinder on the surface plate covered
with #400 grit wet-or-dry sandpaper. Using light
pressure, move the cylinder in a figure eight
motion. Inspect the sealing surface for any indica-
tion 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 cylin-
der in a figure eight motion until a uniform bright
metallic finish is attained.
CC997
Inspecting Cam Chain Guide
1. Inspect cam chain guide for cuts, tears, breaks, or
chips.
2. If the chain guide is damaged, it must be replaced.
Honing Cylinder
1. Using a slide gauge and a dial indicator or a snap
gauge, measure the cylinder bore diameter in three
locations from top to bottom and again from top to
bottom at 90° from the first measurements for a
total of six measurements. The trueness
(out-of-roundness) is the difference between the
highest and lowest reading. Maximum trueness
(out-of-roundness) must not exceed specifications.
! CAUTION
Water or parts-cleaning solvent must be used in
conjunction with the wet-or-dry sandpaper or dam-
age to the sealing surface may result.
! CAUTION
Water or parts-cleaning solvent must be used in
conjunction with the wet-or-dry sandpaper or dam-
age to the sealing surface may result.