Measuring valve projection
1.
Check TDC position of piston in cylinder A1:
• If the rocker arms are unloaded on cylinder A1, the piston is in firing TDC.
• If the rocker arms are under load on cylinder A1, the piston is in overlap TDC.
2.
Measure valve projection for each valve in two crankshaft positions (firing TDC and overlap TDC for cyl-
inder A1) according to the diagram. Diagram (→ Page 150).
3.
Release adjusting screw (1) and remove
valve bridge. Do not remove rocker arm (2)!
4.
Measure distance between valve stem end
and cylinder head top at the spark plug
bore with depth gauge (see figure).
• The specified value for a new cylinder
head: 93.8 mm.
• Admissible wear: 3 mm.
• If the measured value is > 96.8 mm,
have the relevant cylinder head replaced
by authorized pesonnel ahead of sched-
ule .
5.
Install valve bridge.
6.
Adjust valve clearance (→ Page 150)
Final steps
1.
Remove barring device (→ Page 137).
2.
Check condition of O-rings at the sleeves, replace if damaged.
154 | Task Description | MS150057/02E 2013-10
TIM-ID: 0000012015 - 003
