Rotax 912 i Series Maintenance Manual page 191

Fig. 18
VALVE GUIDE CHECK
See Fig. 19
NOTICE
WARNUNG
If the wear limit has been reached, the valve
guide must be replaced.
Step
1 Check the valve guide visually for dam-
age and wear.
2 Inspect the inner diameter of the valve
guide.
Fig. 19
Effectivity: 912 i Series
Edition 1/Rev. 0
BRP-Powertrain
MAINTENANCE MANUAL
Procedure
06448
VALVE CHECK
NOTICE
WARNUNG
Replace the valve if the valve stem is out of
specification, is damaged or shows traces of
wear.
Step
1 Check the valve visually for damage and
wear.
2 Determine the valve stem diameter and
check the valve disc for wear.
3 Check the valve end face for pitting.
4 Check the valve stem for any deposits.
The valve stem diameter VTO is mea-
NOTE:
sured in the edge region of the run-
ning surface of the valve stem.
Fig. 20
1
3
2
1. Valve stem
3. Retaining grooves
NOTICE
WARNUNG
Oil residues up to max. 20 % of the running sur-
face are permissible.
At greater values, the valve may have already
been overheated and must be replaced. Risk of
valve fracture at the weld point.
Procedure
4
06449
2. Valve end face
4. Max. oil residues
72-30-00
Page 13
July 01/2012