How do our Injectors Work

[afp]

I have heard our injectors use oil pressure to help regulate the fuel pulse. Is this right? How do they work? I thought they just released pressure from the fuel pump. I have now heard they increase fule pump pressure.......

Blaine

[Kennedy]

HEUI systems as use by Cat and Navistar use HP oil to drive the injectors. The Dmax uses a common rail already charged with max psi to deliver fuel to the injectors which allow fuel to pass only when the solenoid is active and psi is above 160 bar.

[D-max Man]

Ford uses the HEUI system like JK said. This system uses oil pressure over fuel to actuate the injectors.

The Bosch injectors use Fuel over Fuel.

Simply put, the fuel is allowed to enter the injector on both sides of the valve with equal pressure. When they want to inject fuel, they open a relief valve on one side reducing the pressure and the higher pressure on the other side moves the valve to inject the fuel. Close the relief valve and the pressure equalizes on both sides returning the valve back to the closed position.