Section 75 (1.6L SOHC Engine): Lubrication: Operation
Engine oil is drawn up through the pickup tube and is pressurized by the oil pump and routed through the oil filter to the main oil gallery running the length of the cylinder block. A diagonal hole in each bulkhead feeds oil to each main bearing. Drilled passages within the crankshaft route oil from the main bearing journals to the connecting rod journals. The main oil gallery also feeds oil pressure to the timing chain tensioner. A vertical hole at the number three main bearing area routes pressurized oil through a restrictor up into the cylinder head. The restrictor that is integral to the cylinder head gasket, provides increased oil flow to the main gallery. Upper engine lubrication is provided by one main feed to the number three camshaft bearing cap. Oil is then routed through the rocker shafts to the remaining camshaft bearing caps and rocker arms/hydraulic lash adjusters. Oil returning to the oil pan from the pressurized components supplies lubrication to the valve stems. The cylinder bores and wrist pins are splash lubricated from directed slots on the connecting rod thrust collar. See Fig 1.