WinGD X72 - Page 286

Maintenance3403−4/A1
Winterthur Gas & Diesel Ltd.
2/ 2
3. Procedure − Piston
Installed
WARNING
Injury Hazard: Before you
operate the turning gear,
make sure that no
personnel are near the
flywheel, or in the engine.
1) Use the turning gear to move the piston
to BDC.
2) Look at the piston head through the
scavenge ports (1, Fig. 2) to find burn
scars.
3) Put the template (94366A) through the
related scavenge port (1).
4) Use the feeler gage (94122) to
measure the depth of the burn scar(s).
Note: You can also use a depth gage to
measure the depth of the burn
scar(s).
5) Remove the template (94366A).
6) If there are more burn scars, put the
template (94366A) through the related
scavenge port (1) and do step 2) and 3)
again.
7) If the burn scars are less than 10 mm,
do step a) and step b):
a) Use an applicable tool to grind the
burn scars.
b) Use emery paper to make sharp
edges smooth.
8) If the burn scars are more than 10 mm,
do step a) to step d).
a) Remove the piston, refer to
3403−1, paragraph 1 and
paragraph 2.
b) Disassemble the piston head,
(refer to 3403−3, paragraph 1 and
paragraph 2).
c) Use surface welding to repair the
piston head to its original
thickness.
d) Assemble the piston (see 3403−3,
paragraph 3).
Note: Before you start the engine, find
the cause of the burn scars.
Piston
2015
94366A
WCH03211
Fig. 2
Maximum 10 mm
1