mxu 400 Manuel atelier : Page 48

           3. Place the cylinder head on the surface plate cov-       2. Inspect the cylinder for pitting, scoring, scuffing,
    ered with #400 grit wet-or-dry sandpaper. Using            warpage, and corrosion. If marks are found, repair
    light pressure, move the cylinder head in a figure         the surface using a cylinder hone (see Honing Cyl-
    eight motion. Inspect the sealing surface for any          inder in this sub-section).
    indication of high spots. A high spot can be noted
    by a bright metallic finish. Correct any high spots     3. Place the cylinder on the surface plate covered
    before assembly by continuing to move the cylin-           with #400 grit wet-or-dry sandpaper. Using light
    der head in a figure eight motion until a uniform          pressure, move the cylinder in a figure eight
    bright metallic finish is attained.                        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
                 ! CAUTION                                     before assembly by continuing to move the cylin-
Water or parts-cleaning solvent must be used in                der in a figure eight motion until a uniform bright
conjunction with the wet-or-dry sandpaper or dam-              metallic finish is attained.
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.




                                                    CC996


Measuring Cylinder Head
Distortion
                                                                                                             CC997
 1. Remove any carbon buildup in the combustion
    chamber.
                                                            Inspecting Cam Chain Guide
 2. Lay a straightedge across the cylinder head; then
    using a feeler gauge, check the distortion factor       1. Inspect cam chain guide for cuts, tears, breaks, or
    between the head and the straightedge.                     chips.
 3. Maximum distortion must not exceed specifications.      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.



                                                   CC141D


Cleaning/Inspecting Cylinder

 1. Wash the cylinder in parts-cleaning solvent.




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