149300-0122 ZEXEL 9 443 612 718 BOSCH PRESSURE-CONTROL VALVE 9443612718 1493000122

Lubrication System
OIL LUBRICATION SCHEMATICThe lubrication system is the pressure type. The oil pump draws oil from the sump through a suction pipe and strainer to the pump. The oil pump is driven by the auxiliary drive group which is driven by the timing gears.Pressure oil flows to the oil cooler. The oil cooler is cooled by water from the cooling system. Coolers on T6.3544 Engines have a bypass valve that allows the oil to go around the cooler in case of a restriction or if the oil is too cold and thick. From the cooler, oil passes through the relief valve. On T6.3544 Engines, the relief valve is two stage. At 205 to 225 kPa (30 to 37 psi), oil is fed by a pipe to the piston cooling jet gallery which is a drilled passage the length of the crankcase, above the camshaft chamber. The piston cooling jets are bolted into the gallery and point into the bottom of each cylinder. Oil is sprayed onto the underneath side of each piston which takes heat from the combustion area. The oil then drains back to sump.At 345 to 415 kPa (50 to 60 psi), oil passes through a single oil filter on 6.3544 Engines or two filters on T6.3544 Engines. Oil then flows to the main oil gallery which is a drilled passage the length of the crankcase. Oil also flows from the filters to the turbocharger bearings on T6.3544 Engines. Passages in the crankcase webs feed oil from the main oil gallery to the main bearings. Passages in the crankshaft carry oil to the big end bearings. Through passages in No. 1, 3, 5 and 7 crankcase webs, oil passes from the main bearings to lubricate the camshaft bearings.The No. 2 camshaft bearing supplies a controlled amount of oil to the rocker shaft assembly, which then flows through a small bleed hole in each rocker lever to lubricate the valves and springs.Pistons, cylinder liners, connecting rod small end bushings, cam lobes and valve lifters are splash and oil mist lubricated.Oil flows from the main oil gallery to the two idler gear hubs. The oil passes through the hubs to radial passages in the idler gears to lubricate the teeth of the timing gears.The auxiliary drive group shaft bearings are lubricated by a passage from the main oil gallery to the front auxiliary drive shaft bearing. Oil then passes around a groove in the bearing journal and through another passage along the outer side of the auxiliary drive housing to the rear auxiliary drive shaft bearing. The upper fuel pump bearing is also lubricated from this passage. Also connected to this outer housing passage is a spray tube which directs oil on to the auxiliary drive shaft (worn gear) and gear assembly (worm wheel).Air Inlet And Exhaust System
6.3544 Engines
AIR INLET AND EXHAUST SYSTEM COMPONENTS
1. Exhaust manifold. 2. Inlet manifold. 3. Engine cylinderThe air inlet and exhaust system components on naturally aspirated engines are: the air cleaner, inlet manifold,