IFI fuel pump function - GF07.12-P-3120-01H
Engine 605, 606
Intermediate stroke function (A)
The rotating eccentric on the camshaft pushes the pressure pin (13/14) against the piston (13/12), which in turn pushes against the compression spring (13/11) (intermediate stroke). This allows fuel to flow from the suction gallery (13/10) via the check valve (13/13) into the pressure chamber (13/15).
Delivery and suction stroke function (B)
The compression spring forces the piston to the left. The fuel from the pressure chamber is delivered via the open check valve and pressure connection (B) to the main fuel filter. At the same time, fuel is drawn into the suction gallery (13/10) as its volume increases.
When the fuel pressure in the pressure chamber (13/15) exceeds a set limit, the force applied by the compression spring (13/11) is no longer sufficient to execute a complete working stroke. This reduces the amount of fuel delivered.