Winterthur Gas X40-B, Maintenance Manual

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Maintenance
2751 − 4/A1
Winterthur Gas & Diesel Ltd.
2/ 2
The wear condition can be checked at any time with gauge 94292 and feeler gauge
94122.
D
Where the precise angle required has been obtained during grinding, a check with
marking blue with the valve on the reground valve seat in the valve cage will show
only a line contact or a very narrow band (extent of contact) starting from the small-
er diameter as shown in Fig. 2.
See also remarks in 2751 − 3 regarding the valve behaviour at running temperature.
D A maximum of 1.5 mm may be ground off the valve seating surface. Valve plates,
where the seat surface has been ground back by more than 1.5 mm can be recondi-
tioned by build-up welding.
D On engines with arduous operating conditions, corrosion may form at the bottom of
the valve plate, after a longer operating time. Exhaust valves can be reconditioned
if the loss of material on the valve plate is less than or equal to 4.5 mm.
Exhaust valves cannot be reconditioned anymore, when the loss of material is more
than 4.5 mm, but can be kept in operation up to 10 mm loss of material.
Note: Reconditioning of exhaust valves may, however, only be carried out by a
Wärtsilä Switzerland Ltd authorized repair workshop.
94292
WCH00292
ÇÇÇÇÇÇÇÇÇÇ
Fig. 2
Fig. 3
Exhaust Valve: Grinding the Seating Surface on the Valve Head
2016