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Engine Rieju
Engine
24
6) ENSURE
that the clutch assembly is in working order.
To do so, ensure that the iron discs are in good condition, that the notches on the cork discs
are not too deformed and that their coating is not burnt. Check that the grooves on the
clutch boss are not too deeply marked; perform the same check on the slots of the clutch
housing. Also check that the
clutch springs are not shorter than the permissible
threshold of 29.5 mm
(F-31); if they are shorter replace them.
7) CAREFULLY
clean the carbon crust from the piston top by means of a common scra-
per, taking care not to damage the piston itself. Check the piston skirt for streaks or seizing.
Check that it is firmly mated to the lubricated piston pin, the surface of which must be in
perfect condition. Make sure that the piston pin can be fitted by manual pressure and that it
does not yield under its own weight.
8) CHECK
the piston rings for faults of any type and make sure that the clearance between
the two ends is within the values shown in the chart.
The checks must be carried out using a feeler gauge. The piston ring must be placed in the
cylinder in a horizontal position (F-32).
9) CHECK
that the cylinder water jacket does not have seizing notches or wear and that
there is no scoring of any kind. By means of a bore gauge, check the cylinder bore in two
directions at 90° the one from the other (one parallel and the other perpendicular to the
axis of the piston pin) (F-33). The maximum permissible ovalisation is 0.03 mm, exceeding
which the cylinder must be replaced.
F-33
F-32
RINGS
DISTANCE
New
Used
0,15 ÷ 0,30 mm
Up to 1,2 mm
