Grasp the connecting rod firmly and pull up
on it. Tap sharply on the top of the rod with
your free hand. If the bearing and crankpin are
in good condition, there should be n o
movement felt in the rod. If movement is felt
or ifthere is a sharp metallic click, measure the
radial clearance with Plastigage as described
in this chapter.
1. Spread the ends of the rings with your
thumbs. or use a ring expander tool, and install
them in the proper piston groove. Note the
a. The side of the ring with a letter or
number mark faces up (Figure 78). If
there is no mark, either side can face up.
b. The top ring has a square cross-section
and is narrower than the second ring; it is
sometimes copper colored, with a
chrome outer edge. The second ring has a
tapered outer edge (Figure 79).
2. Coat the connecting rod holes and piston
holes with clean engine oil.
When assembling used parts, be sure to
install each piston and pin on the same
rod from which it was removed.
Oil the piston pin and push it in the piston
until the end extends slightly beyond the inside
of the boss (Figure 80).
4. Place the piston over the connecting rod
with the arrow on the top ofthe piston pointing
forward (Figure 81). Line up the pin with the
rod small end and push the pin into the piston
until it is even with the circlip grooves.
It may be necessary to heat the piston
slightly with a rag soaked in hot water or
use a homemade tool to push the pin in
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