Valve protrusion – Measurement
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 protrusion for each valve in two crankshaft positions (firing TDC and overlap TDC cylinder A1)
according to the diagram. Diagram (→ Page 155).
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 sliding 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 au-
thorized personnel ahead of schedule .
5.
Install valve bridge.
6.
Valve clearance – Adjustment(→ Page 155)
Final steps
1.
Remove barring tool (→ Page 141).
2.
Check condition of O-rings at the sleeves, replace O-rings if damaged.
MS150034/04E 2016-11
| Valve Drive | 159
TIM-ID: 0000012015 - 004
