2nd Test

2nd Test

Checking maximum fuel supply pressure (or efficiency of electric pump)

The same connections as in the previous test apply, then:

• close the fuel tap lever B;
• operate the electric pump with the engine switched off, as described on the previous page: the pressure should not exceed 5 bar (pump safety valve calibration). If this is not the case, replace the electric pump because it is defective.

If in the 1st test (see previous page) the pressure value measured was more than 1 ± 0.1 bar then it is necessary to:

• disconnect the fuel return pipe from the pressure regulator and replace it, temporarily, with pipe going into a suitable container for collecting the fuel;
• operate the electric pump, with the engine idling, then read the pressure value shown on the gauge:
  1. if it reaches 1 ± 0,2 bar the fuel return pipe to the tank should be replaced because it is obstructed or bent,
  2. if it exceeds 1 ± 0,2 bar the regulator is defective and therefore the injector holder turret should be replaced.

3rd Test

Checking injector seal

To check whether the injector is dripping, simply carry out the connection for the 1st test (checking regulation pressure), then operate the electric pump with the engine switched off. When the regulation pressure is reached, close the fuel tap control lever A.

Then:

• switch off the electric pump,
• observe whether as soon as it stabilizes (i.e. decreases slightly) the pressure remains constant for about 60 s,
• after having supplied the electric pump with the engine switched off, observe whether the injector or any connecting sections are dripping.

If necessary, replace any injector which is dripping and/or renew the defective seal which is leaking.