Chevrolet Equinox Service Manual: Lubrication Description

A structural diecast aluminum oil pan incorporates an oil suction tube and a windagetray. The oil suction tube is bolted into the oil pan and seals to the bottom of theblock with O-ring gasket. The windage tray is bolted to the upper portion of the oilpan and reduces friction losses at high speed.

A crankshaft driven gerotor oil pump with internal pressure-relief valve is mountedto the front of the engine block and pulls oil from the oil suction tube through thelower passage in the engine block. The oil pump then directs the flow of pressurizedoil back through the upper passage in the block to the left side of the engine blockwhere the oil filter adapter is mounted.

An oil filter adapter is mounted with a gasket to the left side of the engine block.

RWD Applications: The oil filter adapter incorporates a top-access, cartridge style oil filter. Thefilter is accessed through a screw on cap with an O-ring gasket. The oil filter adaptercap has a built-in oil bypass valve. The oil filter adapter housing incorporates adrain back control valve and a threaded oil pressure sending unit. Oil flows throughthe lower passage in the oil filter adapter up to andthrough the oil filter cartridge. Filtered oil travels back through the upper passageof the oil filter adapter and back into the engine block.

FWD Applications: An oil filter adapter is mounted with a gasket to the left side of the engine block.The oil filter adapter incorporates a bottom-access, spin-on oil filter. The oil filteradapter housing incorporates a threaded oil pressure sending unit. Oil flows throughthe lower passage in the oil filter adapter to and through the oil filter. Filteredoil travels back through the upper passage of theoil filter adapter and back into the engine block.

Oil is directed up and across the engine block front through several drilled passages.These front passages feed oil to each cylinder head, oil to the passage for the mainbearings and piston oil jets, oil to the right and left secondary idler sprockets,and oil to the primary timing drive chain tensioner.

Each cylinder head passage directs oil into the cylinder head where it is directedto oiling circuits for the stationary hydraulic lifter assemblies (SHLAs) and thecamshaft bearing journals. Oil is also directed through-2 passages each with a spring-loadedcheck-ball valve to the 2-chambers where the camshaft position actuator oil controlsolenoid valves are mounted. Each chamber contains a camshaft position actuator oilcontrol solenoid valve with built-in oil filter screen. One camshaft position actuatoroil control solenoid valve is used to control the exhaust camshaft position actuatorand 1-camshaft position actuator oil control solenoid valve is used to control theintake camshaft position actuator. The engine control module (ECM) electrically controlseach camshaft position actuator oil control solenoid valve. When energized by theECM the camshaftposition actuator oil control solenoid valve directs oil to pass up through the cylinderhead front camshaft bearing cap. Oil passes through the camshaft bearing cap passageinto oil holes drilled into the side of the front camshaft journal and onto the frontof the camshaft mounting surface. Oil passes through to matching passages in the camshaftposition actuator. Oil is directed by the camshaft position actuator oil control solenoidvalveto the appropriate passage in the system to pressurize oil on the vanes on the insideof the of the camshaft position actuator. Oil acting on the vanes rotates the camshaftmounted to the inner camshaft position actuator rotor relative to the sprocket mountedto the outer camshaft position actuator housing. An internal lock pin locks the innerrotor to the outer camshaft position actuator housing at idle and maintains the camshaftpositionactuator in the home or default position during start-up conditions. Oil pressuredirected by the camshaft position actuator oil control solenoid valve unlocks thepin and allows the camshaft position actuator to function. An additional passage inthe cylinder head also directs oil to the secondary timing drive chain tensioner mountedto each cylinder head.

The oil passage that supplies oil to the main bearings also supplies oil to pressure-actuatedpiston-cooling oil jets. Each oil jet is mounted between opposing cylinder bores anddirects oil to the 2-bores to provide extra cooling and control piston temperatures.

Oil is directed from the front passages to the front of the block where the rightand left secondary idler sprockets and the primary timing drive chain tensioner aremounted. Each camshaft timing drive chain tensioner relies on a gasket in order tomaintain an oil reserve after the engine is turned OFF. All camshaft timing drivechain tensioners incorporate a small oil jet to supply an oil spray onto the camshafttiming drive chain components.

Oil returns to the oil pan sump either through the camshaft timing drive chain areaor through the cast oil drain back passages on the outboard walls of the cylinderheads and engine block.