This document describes the main components and assembly of a marine diesel engine. It outlines the key parts including the cylinder cover, piston, cylinder liner, crosshead, connecting rod, and crankshaft. It explains that the cylinder cover attaches the exhaust valve and fuel valves and has bores for other components. The piston consists of a crown and skirt attached with screws and wiring. The cylinder liner is tightened by the cylinder cover to allow expansion during heating. The crosshead connects the piston to the crankshaft via the connecting rod to transfer power. The crankshaft has main bearings lubricated by an oil pipe system. The bedplate supports the main bearings and engine.

1. Universidad Nacional Experimental Marítima del Caribe
Vicerrectorado Académico
Coordinación de Idiomas
Maritime Engineering
Marine facilities
Marine Diesel Engine
Prof: Lisbeth Belisario

2. Diesel Engine
o A ship’s reciprocating
machine (the internal
combustion engine)
o No diesel engine is a
single cylinder engine,
there may be as many
as twelve driving one
crankshaft, but each
cylinder is sufficient in
operation

3. Main parts of the diesel engine
Cylinder cover
Piston
Cylinder liner
Crosshead
Connecting rod
Crankshaft
Assembly of large parts

4. Cylinder cover
The cylinder cover is made of
steel and has a central bore for
the exhaust valve, which is
attached by means of four
studs. The cover furthermore
has bores for the fuel valves,
which are mounted with tubular
spacers and nuts. Other bores
have been provided for starting
valve, starting air inlet, safety
valve and indicator cock.

5. PISTON
The piston consists of two main parts:
 Piston Crown
 Piston Skirt
The piston crown is tightened to the
upper end of the piston rod by means of
screws. The screws are locked with
locking wire.
The piston skirt is tightened to the
piston crown by means of flanged
screws. The screws are locked with
locking wire.

6. The cylinder liner is
tightened against the top of
the cylinder frame by the
cylinder cover, so that it
can expand freely
downwards when heated
during the running of the
engine.
Cylinder liner

7. Crosshead with
connecting rod
The crosshead is provided with
two guide shoes fitted floating on
the crosshead ends.
The centre part of the
crosshead is housed in the
crosshead bearing.
The connecting rod
connects the piston to the
crankshaft and is
responsible for transferring
power from the piston to the
crankshaft and sending it to
the transmission.

8. The crankshaft is semi-built,
i.e. the parts are either shrunk
or welded together.
The main bearings are
lubricated via a main
lubricating oil pipe that
branches off to the individual
bearings, whereas oil for
lubricating the crankpin
bearings is supplied from the
crossheads through bores in
the connecting rods.
Crankshaft

9. Assembly of large parts
The bedplate is made in one section,
consisting of two welded,
longitudinal girders and a number of
cross girders which support the main
bearings. The main bearings, which
are of the thin-shell type, consist of
steel shells, lined with tin-aluminium
and coated with a tin-flash layer.

10. MAIN ENGINE