Checking valve clearance in two crankshaft positions
1.
Check TDC position of piston in cylinder A1:
• The piston is at firing TDC when the rocker arms are unloaded on cylinder A1.
• The piston is at overlap TDC when the rocker arms are under load on cylinder A1.
2.
Check valve clearance with cold engine:
• Inlet valves (long rocker arm) = 0.2 mm
• Exhaust valves (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.
Check distance between valve bridge and rocker arm using a feeler gage.
5.
Adjust valve clearance if the deviation from the desired value exceeds 0.1 mm.
Adjusting valve clearance
1.
Release locknut (1).
2.
Insert feeler gage between valve bridge and
rocker arm.
3.
Turn adjusting screw (2) with Allen key un-
til appropriate valve clearance is set.
4.
Feeler gage must just pass through the
gap.
5.
Tighten locknut (1) to the specified tightening torque, holding adjusting screw (2) firmly.
Name
Size
Type
Lubricant
Value/Standard
Locknut
Tightening torque
(Engine oil)
90 Nm + 9 Nm
6.
Replace or rectify adjusting screws and/or locknuts which do not move freely.
7.
Check valve clearance.
Final steps
1.
Remove barring gear (→ Page 133).
2.
Install cylinder head cover (→ Page 143).
142 | Task Description | MS150066/02E 2013-02
TIM-ID: 0000012224 - 005
