WinGD WARTSILA RT-flex58T-D, Maintenance Manual

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Maintenance
3403 − 4/A1
RT-flex58T-D
Winterthur Gas & Diesel Ltd.
1/ 1
Tools:
1 Feeler gauge 94122
1 Template 94366
1 Template 94366A
Every time a piston is pulled out, the piston top surface contour must be checked
with template 94366 and with feeler gauge 94122. The template is placed on the
topmost piston ring and rotated around the piston axis (see Fig. ’A’).
D Where burn scars are only slight it is sufficient to grind them over and to
smooth sharp-edged zones with emery cloth. Where, however, burn scars ex-
ceed x = 10 mm the original material thickness must be restored by surface
welding. This entails the removal of the piston crown.
Before re-starting the engine, the reason for such heavy burns should be estab-
lished. The causes must be remedied.
Causes of heavy burn scars may be:
− Poor combustion
− Worn nozzles
− Heavy local carbon deposits on top of the piston
crown etc.
PISTON RING
Template 94366A should be used if the shape of the
crown top of a piston in situ has to be checked.
As shown in Fig. ’B’, the template is to be pushed
through one of the scavenge ports of the cylinder lin-
er and placed on top of the piston crown.
94366
94366A
x
x
A
B
003.321/00
003.321/00
Piston
Checking Piston Top Surface
2013
CHECK