Operating instructions

Diagram for 16V engines (two
crankshaft positions)
1 Cylinder A1 is in firing TDC
2 Cylinder A1 is in overlap TDC
I Inlet valve
X Exhaust valve
Diagram for 20V engines (two
crankshaft positions)
1 Cylinder A1 is in firing TDC
2 Cylinder A1 is in overlap TDC
I Inlet valve
X Exhaust valve
Checking valve clearance at two crankshaft positions
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. Check valve clearance adjustment with cold engine:
• Inlet (long rocker arm) = 0.2 mm
• Exhaust (short rocker arm) = 0.5 mm
3. Check all valve clearances in two crankshaft positions (firing TDC and overlap TDC of cylinder A1) as
per diagram.
4. Use feeler gauge to determine the distance between valve bridge and rocker arm.
5. If the deviation from the set value exceeds 0.1 mm, adjust valve clearance.
MS150047/02E 2012-03 | Task Description | 121
TIM-ID: 0000000922 - 008