Volvo Penta TAMD61A, Workshop Manual

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Cylinder block
The cylinder block is cast in one piece and is made of
special cast iron alloy. The tension forces in the cyl-
inder head screws, caused by combustion pressures,
are transmitted by stiffened sections in the interior
walls of the cylinder block to the main bearings.
The camshaft bearings are broached to the correct di-
mension after assembly.
Cylinder block
Cylinder liners
The cylinder liners are of the wet type and are replace-
able. They are made from centrifugal cast iron. The
cylinder liners have a so-called “Flame edge”, please
refer to pos. 4. The flame edge, which fits a groove in
the cylinder head, reduces the stress on the cylinder
head gasket.
Four rubber O-rings are used to seal the cylinder
liner. The three lower rings are located in turned
grooves in the cylinder block. These rings are made of
different materials. The lowest seal ring (violet) is
made from fluorocarbon rubber (FPM), whereas the
two upper rings in the lower liner seal are identical and
are made of ethylene-propylene rubber (EPDM).
Note. There have been two previous versions of the
seal kit. In the first version, the two lower seal rings
were identical and were made of fluorocarbon rubber
(black with a green or yellow spot), whereas the upper
seal ring in the lower cylinder liner was made of ethyl-
ene-propylene rubber (EPDM), and was marked with
two white paint spots. In another design, all the lower
seal rings were identical and were made of fluorocar-
bon rubber (marked with a green or yellow spot).
WARNING! Special safety rules apply to fluoro-
carbon rubber which has been exposed to high
temperature. Please refer to page 8.
Cylinder liner
1 Cylinder head 3 Cylinder liner
2 Cylinder block 4 Flame edge
Design and function