MAK M20, Operating Instructions Manual

Page: 49 / 456

Monitoring of operation
Exhaust system/Firing pressure
A3.06.06.01
M20/M25/M32/M43
en / 11.05.2000 BA000498 1/1
Ĺ
The engine is designed so that an adjustment of delivery take-up as well as filling of the individual
cylinders is no longer necessary.
The individual erection heights of the injection pumps of the individual cylinders are secured by
ground, cylinder-tied, firmly mounted plates. Owing to this measure, all tolerances are eliminated
between the base circle of the cam up to the upper edge of the push rod.
The injection pumps also have very narrow tolerances between the pump foot and the control edge
of the pump element so that every pump can be used on every cylinder.
As the camshaft is assembled from individual sections per cylinder, there are very small differences
in the delivery take-up of the individual cylinders in the scope of manufacturing tolerances for the
angular position of the cams and their accidental summation.
The maximum firing pressure is set at the camshaft drive gear which has a hydraulic detachable
shrink brace for this pupose.
To prevent the existing firing pressure differences from being balanced by adjusting the filling at
the injection pump, the engine does not have this adjustment possibility. An adjustment of the
filling would result in the cylinders having different performances and torques.