PISTON 4S5943 - Caterpillar

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 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 plate provides improved reusability and durability. A thin gasket 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 combustion gases, water, and oil.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 the rotation of the camshaft. 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 are drilled from the piston oil ring groove to the interior of the piston. These holes return excess oil from the oil ring groove 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 to fit within the 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 to reduce the