GAS GAS EC FSE 400 - SERVICE 2002 & 2003, Руководство по обслуживанию

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Inspection and Maintenance
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Upper narrowing cutting operation
If the contact surface is too high up the valve, or
if it is too wide, use the 30º knife (inlet side) and
the 15º knife (exhaust side) to lower and narrow
it.
Final seat-cutting operation
If the contact surface is too low down the valve,
or if it is too narrow, use the 60º knife to lift and
widen it. If the contact surface is too high up the
valve, or if it is too wide, use the 15º knife to lower
and narrow it to the correct width.
Upon achievement of the correct seat position
and width, use the 60º knife very slightly to remove
any burrs resulting from the previous cutting
operations.
CAUTION!
Do not use any burnishing compounds after
completing the final cutting operation. A completed
valve seat must show a velvety finishing, but this
should not be exceedingly polished or bright. This
should provide a smooth surface for the final settling
of the valve, which will have place during the first
few seconds of the running of the engine.
NOTE:
After completing the maintenance of the valve seats,
fit the cylinder head and checl the clearance of the
tappets. (2-5 to 2-8)
Contact surface is too high and too wide on
the valve working area.
Contact surface is too low and too
narrow on the valve working area.
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