33
CC390D
4. At this point, repeat step 1 and if any measurement
exceeds the limit, the cylinder must be replaced.
Measuring Camshaft Lobe Height
1. Using a micrometer, measure each cam lobe height.
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2. The lobe heights must exceed minimum specifica-
tions.
Inspecting Camshaft Bearing/
Sprocket
1. Inspect the camshaft bearings for roughness during
rotation or signs of discoloration.
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2. Inspect the timing sprocket for excessive wear.
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Installing Top-Side
Components
A. PISTON
B. CYLINDER
1. Lubricate the piston pin, connecting rod, and piston
pin bore with motor oil; then install the piston on the
connecting rod making sure there is a circlip on each
side and the open end of the circlip is directed
upwards or downwards.
NOTE: The piston should be installed so the word
“IN” points upward.
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2. Place the two alignment pins into position. Place a
new cylinder gasket into position; then place a piston
holder (or suitable substitute) beneath the piston skirt
and square the piston in respect to the crankcase.