ENGINE
INSPECTION AND REPAIR
4-28
5. Polish (grind):
• Valve face
• Valve seat
D The seat is thin and is
resting on the valve internal face.
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• Apply molybdenum disulfide-based oil on
the valve stem.
• Install the valve on the head.
• Turn the valve until its face and seat are
polished. Then, clean it using paste.
CAUTION:
Take care to prevent the paste from entering
into the gap between the valve stem and the
guide.
Polishing steps (grinding):
• Apply a coarse abrasive paste to the valve
face.
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NOTE:
After the valve seat milling or the valve
and valve guide replacement, the valve seat
and face should be polished.
To center the seat and
establish an 1,0 mm
width
30°
45°
Desired result
Milling cutter
To center the seat and
increase the width.
60°
45°
Desired result
Milling cutter
C
D
C The seat is thin and is resting on the
external side of the valve face.
