Is the adjustment supposed to be done on a hot engine or a cold one?

you can do it when engine is hot or cold
with engine cold approx 20C/68F.
with engine warm approx 60C/140F.
0.05mm higher warm engine intaske & exhaust.
hope this help.

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MB STARS Master Guild Technician,12 years MB tech
5 years independent shop owner

I have heard it both ways, an MB training instructor said you drive it hot, adjust it hot. In colder climates lot of old timers say to adjust it cold becasue you want it to start up in zero degree weather (with help from the block heater). I do it hot because I drive it before I do a major service....

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