1. High-pressure oiling system supplies oil pressure for fuel injector operation. See Fig. 72.
During initial start or cold start, gear-driven high pressure oil pump receives unfiltered engine oil from driver-side valve lifter oil galley through anti-drain check ball.
2. Once engine starts or during warm engine starts, anti-drain check ball closes and high pressure oil pump receives filtered engine oil from high pressure oil pump reservoir.
3. High-pressure oil pump delivers engine oil through oil rail in cylinder head at pressures of 2600-3000 psi (42.19- 210.93 kg/cm ) to fuel injectors.
4. During initial start or cold start, the high pressure oil pump receives unfiltered oil from the left side valve lifter oil gallery through the anti-drain back check ball valve.
5. Once the engine starts or during warm engine starts, the check ball closes and the high pressure oil pump receives filtered oil from the high pressure oil pump reservoir.
6. The high pressure oil pump pumps the oil under extremely high pressures 600-3,000 psi (42- 2211 Kg/Cm ) through the left and right side high pressure supply hoses to the high pressure oil rails (integral to the cylinder heads).
7. Once in the oil rail, the oil is fed to the fuel injector bores through 4 oil feed galleries drilled and machined in the cylinder head. The high pressure oil then actuates the fuel injectors.
