Procedures

Preparation
- Cylinder head removed. [1][2]Procedures
- Valve springs removed.
- Valves removed

Overview
- Clean, inspect valves visually.
- Inspect valve stem for runout (max. 0.03 mm).
- Inspect valve seat for runout (max. 0.05 mm).
Refinish as required.
- Inspect dimensions and angles, refer to tables below.

Valve Dimension Tables

Part 1 Of 3:

Part 2 Of 3:

Part 3 Of 3:

NOTE: The stem of the exhaust valve is filled with sodium.





CAUTION:
- Unusable valves filled with sodium should be neutralized before scrapping.
- They should therefore be gathered by the relevant workshop personal and returned to:
Mercedes-Benz AG
Work Marientelde
Daimlerstralie 145
Anlieferstalle KST 3153
Arbeitsvorbereitung TAI
- Or Other suitable scrapping facility

Procedures





1. Clean valves and conduct a visual inspection.
- Valves with scorched valve disc, insufficient height (h) of valve disc or with worn or scared valve stem should be replaced.





2. Measure runout at valve stem.
- If a runout of more than 0.03 mm is measured, replace valve.





3. Machine valve seat.
- Pay attention to operating instructions of machining equipment and setting angle (a) 45° + 15'.

CAUTION:
- If conducting facing work on cylinder head and re-setting of valve seats, always replace valves.
- The valve seats of valves as of model designation M119.98x must not be remachined; these should be replaced when performing repairs.

4. Measure runout at valve seat and height (h) of the valve disc.
- If the runout is greater than 0.05 mm or the height (h) is less than the specification in the tables above, replace the valve.