
22 RENR9968-02
Systems Operation Section
i02290289
Basic Engine
SMCS C ode: 1200
Cylinder Block Assembly
The cylinders in the left side of the block form a 65
degree angle with the cylinders in the right side. The
main bearing caps are fastened to the block with four
bolts, two bolts through each bearing cap and two
bolts through the side of the block.
The cylinder liners can be removed for replacement.
The top surface of the block is the seat for the cylinder
liner flange. Engine coolant flows around the liners
in order to keep the liners cool. Three O -ring seals
around the bottom of the liner make a seal between
the liner and the cylinder block. A filler band goes
under the liner flange. This makes a seal between the
top of the liner and the cylinder block. A steel spacer
plate is used between the cylinder head and the
block. The spacer p late pro vid es improved reusab ility
and durability. A thin g asket is used between the
plate and the block. This thin gasket seals water
and oil. A thick gasket of metal and graphite is used
between the plate and the head. This thick gasket
seals the comb ustion gases, wa te r a nd o il.
Cylinder Head Assembly
The cylinder heads are a one-piece cast iron head.
The cylinder head supports the camshaft. Steel
reinforced camshaft bearings are pressed into each
bore for the camshaft. The bearings are lubricated
under pressure. The cylinder head contains two inlet
valves and two exhaust valves for each cylinder,
which are controlled by a rotating camshaft fo r each
cylinder. Bridge dowels have been eliminated as the
valve train uses floating valve bridges.
The unit injector is mounted in a stainless steel
adapter. This adapter has been pressed into the
cylinder head injector bore.
Pistons, Rings And Connecting
Rods
The piston is a one-piece design that consists of a
forged steel crown and a skirt. The piston is retained
by the piston pin to the small end of the connecting
rod. The pistons have three rings that are located
in grooves in the steel crown. These rings seal the
combustion gas. The rings provide control of the oil.
The top ring has a barrel face. This ring is a Keystone
ring with a plasma face coating. The second ring has
a tapered face and the ring has a coating of chrome
finish for the face. The third ring is the oil ring. The
third ring has a coil spring expander. There are four
holes that a re drilled from the pisto n o il ring groove t o
the interior of the piston. These holes return excess
oil from the oil rin g gro ove to the crankcase.
The connecting rod is a conventional design. The
cap of the connecting rod is attached to the shank by
four bolts that are threaded into the shank. Each side
of the small end of the connecting rod is machined
at an angle of 12 degrees in order to fi twithinthe
piston cavity.
Crankshaft
The crankshaft converts the combustion force in the
cylinder into rotating torque. A vibration damper is
used at the front of the crankshaft in order to reduce
the torsional vibrations.
The cran ksh a ft drives a group of gea rs on the front
and the rear of the engine. These gear trains provide
power for the following components: camshaft, water
pump, oil pump, fuel transfer pump, and accessory
items that are specific t o the application.
The cylinder block has seven main bearings that
support the crankshaft. The cylinder block uses four
bolts to hold each of the be aring caps into the block.
Pressurized oil is supplied to all bearing s urfa ces
through drilled holes in the webs of th e cylind er
block. The oil then flows throu gh drilled holes in the
crankshaft in order to provide oil to the connecting
rod bearings.
Seals and wear sleeves are used at both ends of the
crankshaft. The seals and wear sleeves are used for
easy replacement and reduction of maintenance cost.