PIAGGIO 2005 XEVO 400ie, Workshop Manual

Page: 131 / 376

Inspecting the valve housings
- Clean the valve seats of any carbon residues.
- Using the Prussian blue, check the width of the
impression on the valve seat " V ".
Characteristic
Standard value:
1 - 1.3 mm
Admissible limit:
1.6 mm
- If the impression width on the valve seat is larger than the prescribed limits, true the seats with a 45°
mill and then grind.
- In case of excessive wear or damage, replace the head.
Inspecting the valves
- Measure the diameter of the valve stems in the three positions indicated in the diagram.
STANDARD DIAMETER
Specification Desc./Quantity
Inlet: 4.987 - 4.972 mm
Outlet: 4.975 - 4.960 mm
MINIMUM ADMISSIBLE DIAMETER
Specification Desc./Quantity
Inlet: 4.96 mm
Outlet: 4.945 mm
- Calculate the clearance between valve and valve guide.
XEVO 400ie
Engine
ENG - 131