Piston (Wrist) Pin And Needle Bearing Inspection - Arctic Cat Cougar Service Manual

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will remain together and not mistakenly
mixed with other similar parts.
7. Lift the piston from the connecting rod.
8. Remove the needle bearing from the connect-
ing rod (Figure 50).
9. Repeat the removal procedure for the other
piston(s).
10. If the pistons are going to remain off for
some time, cover the end of each rod with a piece
of foam insulation tube or a shop cloth to protect
it.
NOTE
Always remove the top piston ring first.
11. Remove the upper ring by spreading the
ends with your thumbs just enough to slide it up
over the piston (Figure 51). Repeat for the lower
nng.
Piston (Wrist) Pin and
Needle Bearing Inspection
1. Clean the needle bearing (Figure 52) in sol-
vent and dry it thoroughly. Use a magnifying
glass and inspect the bearing cage for cracks at
the comers of the needle slots and inspect the
needles themselves for cracking. If any cracks
are found, the bearing must be replaced.
2. Check the piston pin (Figure 53) for severe
wear, scoring or chrome flaking. Also check the
wrist pin for cracks along the top and side sur-
faces. Replace the piston pin if necessary.
Pad Nut
Washer
Threaded rod
CHAPTER FIVE
3. With a micrometer, measure the piston pin
outside diameter (Figure 54) at several different
points and compare to the service specification
listed in Table 2-9. If the piston pin is worn,
replace the pin and bearing as a set.
4. Measure the piston pin bore in the piston with
a snap gauge (Figure 55), then measure the snap
gauge with a micrometer to determine the pin
bore diameter. Compare measurement with serv-
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