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 loaded on cylinder A1, the piston is in overlap TDC.
2.
Check valve clearance with cold engine:
• Inlet (I) = 0.3 mm;
• Exhaust (X) = 0.4 mm.
3.
Check all valve clearances at two crankshaft positions (firing TDC and overlap TDC) according to the
table below.
Position
Cylinder
1
2
3
4
5
6
7
8
9
10
12V
Firing TDC in cylinder A1
Bank A
I X
I –
– X I – – X – –
Bank B
I –
– – – X I –
I X – X
Overlap TDC in cylinder A1
Bank A
– – – X I – – X I –
I X
Bank B
– X I X
I – – X – –
I –
I
Inlet: Inlet valve adjustment admitted
X
eXhaust: Exhaust valve adjustment admitted
–
Exhaust valve adjustment not allowed
4.
Use feeler gauge to determine the distance between valve bridge and rocker arm.
5.
If the deviation from the reference value exceeds 0.1 mm, adjust valve clearance.
Adjusting valve clearance
1.
Loosen locknut (1) and unscrew adjusting
screw (2) by a few threads.
2.
Insert feeler gauge (3) between valve
bridge and rocker arm.
3.
Readjust adjusting screw (2) so that the
feeler gauge (3) just passes through the
gap.
4.
Tighten locknut (1) with torque wrench to the specified tightening torque, holding the adjusting
screw (2) to prevent it from turning.
Name
Size
Type
Lubricant
Value/Standard
Locknut
M18
Tightening torque
50 Nm + 5 Nm
5.
Check if the feeler gauge (3) just passes through between valve bridge and rocker arm.
Result:
If not, adjust valve clearance.
Final steps
1.
Remove barring tool.
2.
Install cylinder head cover (→ Page 47).
3.
Install air filter (→ Page 67).
46 | Task Description | MS150111/01E 2014-05
TIM-ID: 0000052123 - 001
