Refitting The Piston Rings - PIAGGIO 2005 XEVO 400ie Workshop Manual

Engine
IF DEVIATIONS (OR RECESSES OR PROJECTIONS) CLOSE TO THE CHANGE OF CATEGORY
ARE MEASURED, REPEAT THE MEASUREMENT AT THE OPPOSED SIDE. TO DO SO, REPEAT
THE TOOL INSTALLATION BY INVERTING ITS POSITION.
Characteristic
Recess / Projection measured 1
- 0.185 - - 0.10
Gasket thickness 1
0.4 ± 0.05
Recess / Projection measured 2
- 0.10 - + 0.10
Gasket thickness 2
0.6 ± 0.05
Recess / Projection measured 3
+ 0.10 ÷ + 0.185
Gasket thickness 3
0.8 ± 0.05

Refitting the piston rings

- Place the scraper ring spring on the piston.
- Install the scraper ring keeping the opening op-
posed to the spring junction and with the writing
"top" facing the piston top. The chamfered side of
the oil scraper ring should always be facing the
piston crown.
- Fit the second lining with the identification letter
or the writing "top" facing the piston crown. In any
case, the step must be facing opposite the piston
top.
- Install the first compression lining in the direction
imposed by the housing.
- It is advisable to use a fitter to facilitate the in-
stallation of the linings.
N.B.
THE TWO PISTON RINGS ARE MADE WITH A TAPERED
CYLINDRICAL CONTACT CROSS-SECTION. THIS IS TO
ACHIEVE A BETTER BEDDING.
- Misalign the lining openings at 120° as shown in the figure.
- Lubricate the components with engine oil.
- The engine uses the first compression lining with an L section.
ENG - 128
XEVO 400ie