0335360 JOHNSON GASKET, Cylinder head, 150

Illustration 1 g03890746
Front side of the block
(1) Main oil gallery
(2) Camshaft oil gallery
(3) Piston cooling jet gallery
(4) Piston cooling jet gallery
(5) Camshaft oil gallery
(6) Sequence valveNote: There is a sequence valve (6) in both the front and rear of the block.
Illustration 2 g06531100
Right-hand side of the engine
(7) Turbocharger oil supply line
(8) Adapter (rear/right oil distribution block)
(9) Engine oil filter base
(10) Engine oil cooler
(11) Engine oil pump
Illustration 3 g06531123
Right-hand side of the engine
(10) Engine oil cooler
(11) Engine oil pump
(12) Suction bell
(13) Engine oil cooler bypass valve
(14) Engine oil pump relief valve
(15) ConnectorEngine oil pump (11) has three gears that are driven by the front gear train. The engine oil pump pulls engine oil from the pan through suction bell (12) and connector (15). The suction bell has a screen to prevent debris larger than 1 mm (0.039 inch) from entering the lube system and damage the oil pump or other lubrication system components prior to the engine oil filters.Relief valve (14) controls the maximum pressure of the engine oil from the engine oil pump. If the pressure from the pump becomes excessive, the relief valve opens and some of the engine oil returns to the inlet of the oil pump.Engine oil cooler (10) reduces the temperature of the engine oil. The engine oil cooler has bypass valve (13) that is designed to open during startup and while the oil is too cold, to improve time to pressure, protect the cooler and speed up the engine warmup.Engine oil filter base (9) holds four spin-on oil filter elements. The base has an internal bypass valve for each filter element. The filter bypass valve will open if there is a restriction in the engine oil filter, and it will open and close briefly to protect the oil filter during engine startup at high speed in freezing ambient temperature. The filter bypass allows the engine to be lubricated if the engine oil filter is dirty (plugged). Extended run time with an open oil filter bypass will damage the engine.Clean engine oil from the engine oil filters goes through adapter (8) into the block. Part of the engine oil goes to right camshaft oil gallery (2). The remainder of the engine oil goes to main engine oil gallery (1).Engine oil galleries (2) and (5) supply engine oil through drilled passages to the camshaft bearings. The engine oil circulates around each camshaft journal. The engine oil then flows through the cylinder head and through the rocker arm housing to the rocker arm shaft. Some of the engine oil lubricates the valve stems. The remainder of the engine oil drains from the cylinder head to lubricate the pushrods, the valve lifters, the camshaft, and the camshaft bearings.Engine oil from main engine oil gallery (1) is supplied to the main bearings through drilled passages. Drilled holes in the crankshaft supply engine oil from the main bearings to the connecting rod bearings. Engine oil from the front of the main engine oil gallery goes to the front of left camshaft oil gallery (5).Two sequence valves (6) allow engine oil from main engine oil gallery (1) to enter engine oil galleries (3) and (4) for piston cooling jets. The sequence valves will not allow engine oil into galleries (3) and (4) for the piston cooling jets until there is pressure in the main engine oil gallery. This reduces the amount of time that is required for pressure buildup when the engine is started.
Illustration 4 g06512278
(16) Piston cooling jet
Illustration 5 g06165422
Piston cooling jet
There is a piston cooling jet (16) 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 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 6 g06531154
Turbocharger oil lines
(7) Turbocharger oil supply lineOil supply lines (7) provide engine oil for lubrication of the turbocharger bearings. The engine oil flows through the turbocharger support into the rear housing.Engine oil is provided to the front and rear gear groups through drilled passages in the front housings, in the rear housings, and in the faces of the cylinder block. These passages are connected to engine oil galleries (2) and (5) for the camshafts.After the oil has completed lubrication, the engine oil returns to the engine oil pan.