1. Do not remove the carbon ridge at the top of
the cylinder bore unless you are going to install
new piston rings or bore or hone the cylinder.
The ridge helps the top ring's compression seal.
2. Check the cylinder walls for scratches; if
evident, the cylinders should be rebored.
3. Measure the cylinder bores, with a cylinder
gauge or inside micrometer. at the points
shown in Figure 55. Measure 2 ways-in line
with the piston pin and at a right angle to the
pin. If any measurement exceeds the wear limit
in Table 1 or if the taper or out-of-round is
greater than 0.002 in. (0.05 mm), the cylinders
must be rebored to the next oversize and new
pistons and rings installed. The liner can be
bored oversize twice, first to 0.020 in. (0.5 mm)
and again to 0.040 in. (1.0 mm). Rebore all
cylinders even though only one may be faulty.
Get the new plsions before you have the
cjYrnders bored. You'll need them to
achreve proper plston/cyllnder
4. Inspect the cam chain guides (Figure 56).
Replace them if visibly damaged or if worn
deeper than the service limit in Table 1 (Figure
1. Check that the top surface of the crankcase
and the bottom surface of the cylinder block
are clean before installing a new gasket. Make
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