32549-ZW4-H01 Honda SCREW (Honda Code 7758691).

Illustration 1 g01192996
Main oil pump and lubrication system schematic (typical example)
(1) Main oil gallery
(2) Camshaft oil gallery
(3) Piston cooling jet gallery
(4) Piston cooling jet gallery
(5) Camshaft oil gallery
(6) Turbocharger oil supply
(7) Sequence valve
(8) Sequence valve
(9) Elbow
(10) Engine oil filter bypass valve
(11) Engine oil cooler
(12) Engine oil cooler bypass valve
(13) Engine oil relief valve
(14) Engine oil pump
(15) Elbow
(16) Suction bell
(17) Engine oil filter housingThis system uses an engine oil pump (14) with three pump gears. The pump gears are driven by the front gear train. Oil is pulled from the pan through suction bell (16) and through elbow (15) by the engine oil pump. The suction bell has a screen in order to clean the engine oil.There is an engine oil relief valve (13) in the engine oil pump. The engine oil relief valve controls the pressure of the engine oil from the engine oil pump. The engine oil pump can put too much engine oil into the system. When there is too much engine oil, the engine oil pressure goes up and the relief valve opens. This allows the engine oil that is not needed to go back to the inlet oil passage of the engine oil pump.The engine oil pump pushes engine oil through engine oil cooler (11) and through the engine oil filters to main oil gallery (1) and through camshaft oil gallery (2). Engine oil cooler (11) lowers the temperature of the engine oil before the engine oil is sent to the filters.Engine oil cooler bypass valve (12) allows engine oil to flow directly to the filters if the engine oil cooler becomes plugged. The engine oil cooler bypass valve also allows engine oil to flow directly to the filters if the engine oil becomes thick. The engine oil cooler bypass valve will bypass the engine oil to the filters above 180 20 kPa (26 3 psi) of oil pressure differential.Cartridge type filters are used. The filters are located in an engine oil filter housing. Cartridge type filters use a single bypass valve that is located in the engine oil filter housing.Clean engine oil from the filters flows through the engine oil line and into the block through elbow (9). Part of the engine oil flows to left camshaft oil gallery (2). The remainder of the engine oil flows to main oil gallery (1).Camshaft oil gallery (2) and camshaft oil gallery (5) are connected to each camshaft bearing by a drilled hole. The engine oil flows around each camshaft journal. The engine oil then travels through the cylinder head and through the rocker arm housing to the rocker arm shaft. A drilled hole connects the bores for the valve lifters to the oil hole for the rocker arm shaft. The valve lifters are lubricated at the top of each stroke.Main oil gallery (1) is connected to the main bearings by drilled holes. Drilled holes in the crankshaft connect the main bearing oil supply to the rod bearings. Engine oil from the rear of the main oil gallery goes to the rear of right camshaft oil gallery (5).Sequence valve (7) and sequence valve (8) allow engine oil from main oil gallery (1) to flow to piston cooling jet gallery (3) and to piston cooling jet gallery (4). The sequence valves begin to open at approximately 130 kPa (19 psi). The sequence valves will not allow engine oil into the piston cooling jet galleries until there is pressure in the main oil gallery. This decreases the amount of time that is necessary for pressure buildup when the engine is started. This also helps hold pressure at idle speed.
Illustration 2 g00281794
Piston cooling and lubrication (typical example)
(18) Piston cooling jetThere is a piston cooling jet (18) below each piston. Each piston cooling jet has two openings. One opening is in the direction of a passage in the bottom of the piston. This passage takes engine oil to a manifold behind the ring band of the piston. A slot (groove) is in the side of both piston pin bores in order to connect with the manifold behind the ring band. The other opening is in the direction of the center of the piston. This helps cool the piston and this lubricates the piston pin.
Illustration 3 g01193001
Center mounted turbochargers (typical example)
(19) Oil supply line
(20) Oil drain lineOn center mounted turbochargers, oil supply lines (19) send engine oil from the front and the rear adapters to the turbochargers. Oil drain lines (20) are connected to a camshaft inspection cover.
Illustration 4 g01193018
Rear mounted turbochargers (typical example)
(19) Oil supply line
(20) Oil drain lineOn rear mounted turbochargers, oil supply lines (19) send engine oil from the rear adapter to the turbochargers. Oil drain lines (20) are connected to the flywheel housing on each side of the engine.Engine oil is sent to the front gear group and the rear gear group through drilled passages. The drilled passages are in the front housing, the rear housing and cylinder block faces. These passages are connected to camshaft oil galleries (2) and (5).After the engine oil has finished lubricating, the engine oil goes back to the engine oil pan.