Inspecting The Engine Block; Upper Block Plane; Cylinder Bore - Volvo Penta D2-55 Workshop Manual

29. Remove the oil pressure valve to allow removal of
the crankshaft and simplify flushing of the oil
channels.
IMPORTANT! Check that the oil pressure valve
on the right side of the block is removed before
removing the crankshaft.
NOTE! Tape the crankshaft gear to protect the bearing
surfaces in the block during disassembly.
30. Remove the locking screws holding the main
bearing caps. Lift the crankshaft out carefully,
complete with caps, backwards.

Inspecting the engine block

Upper block plane

Check that the upper engine block plane does not
have any cracks or other damage. Also check that it
is not warped (in the same way as for the cylinder
head).
Max warpage, please refer to "Technical Data".
Change the engine block if it is outside the tolerances.

Cylinder bore

Check that the cylinder bores are not scored or dam-
aged in other ways.
Measure the cylinder bores at the upper and lower
turning positions for the piston rings (app 10 mm and
100 mm below the engine block plane) and also in the
middle. Measurement should be done with an internal
dial gauge and both along and transverse to the en-
gine block (A and B).
Concerning max. permitted cylinder diameter, see un-
der "Wear tolerances" in Technical data.
Group 21 Short block
29