Yamaha YFM400FWA 2000 5GH3-AE1, Руководство по обслуживанию

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ENG
CYLINDER AND PISTON
3rd step:
●
Find the piston-to-cylinder clearance with
the following formula.
●
If out of specification, rebore or replace
the cylinder, and replace the piston and
piston rings as a set.
*********************************
Piston-to-cylinder clearance =
Cylinder bore “C” –
Piston skirt diameter “P”
Piston-to-cylinder clearance:
0.040 ~ 0.065 mm
(0.0016 ~ 0.0026 in)
<Limit>: 0.15 mm (0.0059 in)
PISTON RING INSPECTION
1.Measure:
●
Ring side clearance
Use a feeler gauge.
Out of specification
→
Replace the piston
and rings as a set.
NOTE:
Clean carbon from the piston ring grooves
and rings before measuring the side clear-
ance.
2.Position:
●
Piston ring
(in cylinder)
NOTE:
Insert a ring into the cylinder and push it
approximately 40 mm (1.6 in) into the cylin-
der. Push the ring with the piston crown so
that the ring will be at a right angle to the
cylinder bore.
a
40 mm (1.6 in)
Side clearance
Standard Limit
Top
ring
0.03 ~ 0.08 mm
(0.001 ~ 0.003 in)
0.13 mm
(0.005 in)
2nd
ring
0.03 ~ 0.07 mm
(0.001 ~ 0.003 in)
0.13 mm
(0.005 in)