Yamaha YFM400FWA 2000 5GH3-AE1, Руководство по обслуживанию

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ENG
CAMSHAFT, ROCKER ARMS AND VALVES
5.Measure:
●
Runout (valve stem)
Out of specification
→
Replace.
NOTE:
●
When installing a new valve always
replace the guide.
●
If the valve is removed or replaced always
replace the oil seal.
6.Eliminate:
●
Carbon deposits
(from the valve face and valve seat)
7.Inspect:
●
Valve seats
Pitting/wear
→
Reface the valve seat.
Runout limit:
0.01 mm (0.0004 in)
8.Measure:
●
Valve seat width
a
Out of specification
→
Reface the valve
seat.
*********************************
Measurement steps:
●
Apply Mechanic’s blueing dye (Dykem)
b
to the valve face.
●
Install the valve into the cylinder head.
●
Press the valve through the valve guide
and onto the valve seat to make a clear
pattern.
●
Measure the valve seat width. Where the
valve seat and valve face made contact,
blueing will have been removed.
●
If the valve seat is too wide, too narrow,
or the seat is not centered, the valve seat
must be refaced.
*********************************
Valve seat width:
Intake:
1.2 ~ 1.4 mm (0.0472 ~ 0.0551 in)
<Limit>: 1.6 mm (0.0630 in)
Exhaust:
1.2 ~ 1.4 mm (0.0472 ~ 0.0551 in)
<Limit>: 1.6 mm (0.0630 in)