Volvo Penta TD520GE Workshop Manual page 84

Checks and adjustments
Acceptable wear
The camshaft does not need to be replaced.
94
Guiding principles for replacement
Under normal circumstances there may be
unevennesses on the surface of the camshaft ridges.
This means that the camshaft must be replaced.
These markings have no negative effect neither on the
engine prestanda nor on the strength of the engine or
its components.
Below, you can see examples of acceptable wear and
unacceptable wear.
Unacceptable wear
NOTE! The camshaft and its belonging rocker arms
must be replaced.
Group 21