BOLT 4I6766 - Caterpillar

Cylinder Block Assembly
Passages supply the lubrication for the crankshaft bearings and the piston crowns. These passages are drilled passages in the oil manifolds. Cooling passages for the top piston ring are located in the top deck of the block. This configuration provides improved rigidity. This configuration will resist the deflection that is caused by combustion.The cylinder liner is an induction hardened liner. A steel spacer plate provides improved reusability and durability.Cylinder Head Assembly
The cylinder head is a one-piece cast iron head. The camshaft is contained within the cylinder head. This improves the rigidity of the valve train. Steel reinforced aluminum bearings are pressed into each journal. The bearings are lubricated under pressure. Bridge dowels have been eliminated as the valve train uses floating valve bridges.Thermal efficiency is enhanced by the use of stainless steel thermal sleeves in each exhaust port. The sleeves reduce the amount of heat rejection to the cooling system. The sleeves then transfer the thermal energy to the turbocharger.The electronic 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
Two-Piece Pistons
The piston is a two-piece articulated design that consists of a forged steel crown and a cast aluminum skirt. Both parts are retained by the piston pin to the small end of the connecting rod. An oil cooling chamber is formed by the lip that is cast at the top of the piston skirt and the cavity that is behind the ring grooves in the crown. The oil flow then returns to the sump through the clearance gap between the crown and the skirt. The pistons have three rings that are located in grooves in the steel crown. The rings seal the combustion gas and 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 ring is double railed and the ring is profile ground. This ring has a coating of chrome finish for the face. The oil 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 drain excess oil from the oil ring.The cap of the connecting rod is attached to the shank by two 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 fit within the piston cavity.Crankshaft
The crankshaft converts the combustion force in the cylinder into rotating torque. The rotating torque powers the equipment. On this engine, a vibration damper is used at the front of the crankshaft in order to reduce the torsional vibrations. The torsional vibrations can cause damage to the engine.The crankshaft drives a group