LUBRICATION
The lubrication system is a full flow filtration pressure feed type.
Scheme 50
| 1 - OIL FLOW TO RIGHT CYLINDER HEAD | 7 - OIL FLOW TO COUNTER BALANCE SHAFT |
|---|---|
| 2 - CYLINDER BLOCK MAIN OIL GALLERY | 8 - OIL PUMP OUTLET TO CYLINDER BLOCK |
| 3 - LEFT CYLINDER HEAD OIL GALLERY | 9 - OIL PUMP |
| 4 - OIL FLOW TO BOTH SECONDARY TENSIONERS | 10 - OIL FLOW TO CRANKSHAFT MAIN JOURNALS |
| 5 - OIL FLOW TO LEFT CYLINDER HEAD | 11 - CRANKSHAFT MAIN BEARING JOURNALS |
| 6 - OIL PRESSURE SENSOR LOCATION | 12 - RIGHT CYLINDER HEAD OIL GALLERY |
Oil from the oil pan is pumped by a gerotor type oil pump directly mounted to the crankshaft nose. Oil pressure is controlled by a relief valve mounted inside the oil pump housing.
The camshaft exhaust valve lobes and rocker arms are lubricated through a small hole in the rocker arm; oil flows through the lash adjuster then through the rocker arm and onto the camshaft lobe. Due to the orientation of the rocker arm, the camshaft intake lobes are not lubricated in the same manner as the exhaust lobes. The intake lobes are lubricated through internal passages in the camshaft. Oil flows through a bore in the No. 3 camshaft bearing bore, and as the camshaft turns, a hole in the camshaft aligns with the hole in the camshaft bore allowing engine oil to enter the camshaft tube. The oil then exits through 1.6 mm (0.063 in.) holes drilled into the intake lobes, lubricating the lobes and the rocker arms.
| FROM | TO |
|---|---|
| Oil Pickup Tube | Oil Pump |
| Oil Pump | Oil Filter |
| Oil Filter | Block Main Oil Gallery |
| Block Main Oil Gallery | 1. Crankshaft Main Journal |
| 2. Left Cylinder Head* | |
| 3. Right Cylinder Head* | |
| 4. Counterbalance Shaft Rear Journal | |
| Crankshaft Main Journals | Crankshaft Rod Journals |
| Crankshaft Number One Main Journal | 1. Front Timing Chain Idler Shaft |
| 2. Counterbalance Shaft - Front Journal | |
| 3. Both Secondary Chain Tensioners | |
| Left Cylinder Head | Refer to ENGINE LUBRICATION FLOW CHART - CYLINDER HEADS: TABLE 2 |
| Right Cylinder Head | Refer to ENGINE LUBRICATION FLOW CHART - CYLINDER HEADS: TABLE 2 |
| * The cylinder head gaskets have an oil restrictor to control oil flow to the cylinder heads | |
ENGINE LUBRICATION FLOW CHART - BLOCK: TABLE 1
| FROM | TO |
|---|---|
| Cylinder Head Oil Port (in bolt hole) | Diagonal Cross Drilling to Main Oil Gallery |
| Main Oil Gallery (drilled through head from rear to front) | 1. Base of Camshaft Towers |
| 2. Lash Adjuster Towers | |
| Base of Camshaft Towers | Vertical Drilling Through Tower to Camshaft Bearings** |
| Lash Adjuster Towers | Diagonal Drillings to Hydraulic Lash Adjuster Pockets |
| ** The number three camshaft bearing journal feeds oil into the hollow camshaft tubes. Oil is routed to the intake lobes, which have oil passages drilled into them to lubricate the rocker arms. | |
ENGINE LUBRICATION FLOW CHART - CYLINDER HEADS: TABLE 2
Scheme 51
- Remove oil pressure sending unit (2) and install gauge assembly C-3292.
- Run engine until thermostat opens.
- Oil Pressure: Curb Idle - 25 kPa (4 psi) minimum 3000 RPM - 170 - 758 kPa (25 - 110 psi)
- If oil pressure is 0 at idle, shut off engine. Check for a clogged oil pick-up screen or a pressure relief valve stuck open.