19
Superior
Technology
Functional description
Beginning of valve stroke
The cam turns on the bucket tappet, the
non-return valve closes and pressure builds up in
the high pressure chamber. The oil trapped in the
high pressure chamber cannot be compressed.
The bucket tapped acts as a rigid element.
Valve stroke
The pressure in the high pressure chamber
increases due to the force the cam exerts on the
tappet. A little oil escapes via the leakage gap so
that the tappet compresses by max. 0.1 mm.
Valve clearance compensation
Compensation of the valve clearance (lash)
begins after the valve has closed. The pressure in
the high pressure chamber drops as the cam no
longer presses against the tappet. The spring
forces the cylinder and bucket apart to such an
extent that there is no clearance between the
bucket tappet and cam. Oil flows out of the
supply reservoir through the now opening
non-return valve into the high pressure chamber.
Engine mechanical systems
MSSP_001_015
MSSP_001_013
High pressure
chamber
MSSP_001_014
Leakage gap
Summary of Contents for SDI 55-5
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