Linhai 2004 ATV 260, Руководство по обслуживанию

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CHAPTER 3A ENGINE
260/ 300 / 400 cc ATV SERVICE MANUAL09.0
CHAPTER 3 ENGINE PAGE. 3A- 32
3. Measure:
z Valve seat width
○
a
Out of specification → Reface the valve seat.
Valve seat width:
Intake:
0.9-1.1mm
<Limit:1.6mm>
Exhaust:
0.9-1.1mm
<Limit:1.6mm>
Measurement step:
z Apply Mechanic’s blueing dye (Dykem) c to
the valve face.
z Install the valve into the cylinder head.
Press the valve through the valve guide and
onto the valve seat to make a clear pattern.
z Measure the valve seat width. Where the valve
seat and valve face made contact, blueing will
have been removed.
z If the valve seat is too wide, too narrow, or the
seat is not centered, the valve seat must be
replaced.
4. Lap:
z Valve face
z Valve seat
NOTE:
After replacing the valve seat, valve and valve
guide, the valve seat and valve face should be
lapped.
Lapping steps:
z Apply a coarse lapping com pound
○
a
to the
valve face.
CAUTION:
Do not let compound enter the gap between the
valve stem and the guide.
z Apply molybdenum disulfide oil to the valve
stem.
z Install the valve into the cylinder head.
z Turn the valve until the valve face and valve
seat are evenly polished, then clean off al com
pound.