Operation

The unit assembly comprises a pump with pre-filter, filter, pressure regulator and fuel level gauge with contact strips.

1. Pump unit
2. Regulator
3. Level gauge
4. Float
5. Electric fuel pump
6. Fuel filter
7. Pre-filter
8. Check valve
9. Fuel return duct

Operation

Fuel is delivered by a volumetric pump able to work with unleaded fuel.
The pump is driven directly by the injection control unit via a dual relay to ensure:

• - pump shut-off if engine rpm falls below a minimum threshold;
• - timed enablement for a few seconds whenever the key is turned to MARCIA, even if the car does not start;
• - enablement of operation while the car is in motion or when the engine is started up.

The pump rotor is moved by a D.C. electric motor supplied at battery voltage. The motor is submerged in the fuel, which cools and cleans the brushes and commutator.