The valves are adjusted on a cold engine. You need a special tool available on the Buy Tools section on this web site, 6th one down, ST3545-14, http://www.peachparts.com/diy/mb_tools/mb_tools.php?page=11

While it says M180, it will work on yours too.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.