S 500 Sedan (140.051) V8-5.0L (119.980) (1996)
Valve Seat: Service and Repair
Replacement
Replacing Valve Seats (Part 1 Of 3)
Preparation
-
Valve guides inspected
Overview
-
Turn out valve seat rings (20 and 21) with ring seat turning tool.
Note tool manufacturer operating instructions.
-
Measure basic bore diameter (D1) with internal measuring instrument.
-
Select valve seat rings (standard size or repair size) according to overlap.
If repair size machine basic bore.
If repair size seat ring bore matching valve seat ring, pay attention to overlap.
-
Cool valve seat ring with liquid nitrogen and insert with a suitable drift.
-
Refinish (machine) valve seats machine.
Valve Seat Ring Data
Engines 119.960/970/972/974
Replacing Valve Seats (Part 2 Of 3)
Engines 119.971/975/980/981/982/985
Replacing Valve Seats (Part 3 Of 3)