Fuel drip tray assembly

FUEL DRIP TRAY ASSEMBLY

Electric fuel pump

1. Electric fuel pump
2. Fuel filter
3. Fuel gauge with float
4. Pressure regulator
5. Gauze pre-filter

The pump is housed inside the fuel tank on a special drip tray which also supports the fuel gauge and it has a filter on the pump inlet.

The pressure regulator is fitted on the pump supply.

The pump is the single stage peripheral flow type and is designed to run on unleaded fuel. The rotor is moved by a d.c. electric motor supplied by a relay and controlled by the control unit to ensure:

• that the pump cuts out if the engine speed goes below a minimum level;
• timed operation (about 5 seconds) each time the ignition key is turned to the ON psition, even if the engine is not started up;
• operation with the engine started up.

The pump is fitted with an excess pressure valve which short circuits the supply with the inlet if the pressure in the supply circuit exceeds around 5 bar to prevent the electric motor from overheating.

In addition, a one-way valve in the supply, prevents the entire fuel circuit from being drained when the pump is not working.

Fuel filter

The fuel filter is in the housing surrounding the pump and does not require periodic replacement.

Fuel pressure regulator

This is a differential, diaphragm device, adjusted during manufacture to a pressure of 3.50±0.05 bar and located in the top part of the drip tray.

The fuel, under pressure (1), coming from the pump, exerts force on the valve (3), opposed by the calibrated spring (2). When the set pressure is overcome, the valve opens and the excess fuel (4) returns to the tank, thereby stabilizing the pressure in the circuit.