Does not look like there is much to it. OM642 engine. Going to try to sell a serpentine belt/tensioner replacement job too. Belt is showing a bunch of cracks. Vehicle is at ~200k miles.

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Jim

Go with MB's (Dunlop?) serpentine belt instead of an auto parts store 'Gates'.......ask me how I know....

Those engines have very long glow plugs that like to snap off in the engine, be very careful when removing them not to break them off, the threads will come out leaving the lower portion of the glow plug in the cylinder head. You can purchase a reaming tool for the bores once out to get all the carbon out. Try removing them with a hot engine, penetrating oil may help but the problem is below the threads (not easy to access).

If you search around you will see they sell air impacts with very low torque to remove glow plugs from these engines, neat idea I am sure a regular 3/8" impact set on the lowest setting is very similar, dial down the air pressure too.