Mercedes-Benz 201.024, Service Manual

Page: 190 / 304

The oil needed for operating the hydraulic valve
clearance compensating elements, flows from
the longitudinal channel and the transverse bores
in the cylinder head to the rocker arm bearing
points. From here it reaches the ring channel (f)
through the bore (h) in the rocker arm and the
reservoir chamber (a) via grooves in the washer
Any air in the reservoir chamber can separate
from the oil (solid oil), with the result that, if
necessary, defoamed oil is led to the working
chamber.
The oil quantity in the reservoir chamber is
sufficient to fill the working chamber under all
engine operating conditions. Any air in the
reservoir chamber can escape to the ring
channel (f) via the grooves in the washer (57)
and from there via the annular gap between
washer and rocker arm and the joint gap of the
snap ring (56).
In order that the hydraulic valve clearance
compensating elements can be supplied with oil
pressure corresponding to the respective engine
speed, oil flows unrestricted via nozzle (A) into
the longitudinal channel (a) in the cylinder head
(pressure-orientated oil feed). The nozzle
simultaneously blocks off the oil return,
preventing the channels up to the hydraulic
elements emptying when the engine is not
running.
The sealing cap (65) is shaped so that it secures
the hydraulic valve clearance compensating
element captive in the rocker arm.
Only store the compensating elements upright,
and do not dismantle them. It is essential that
rocker arm, compensating element, washer (57)
and ball socket (55) are installed in their original
position.
P
05.0906