8.8.4 Water/fuel separator filters for engines

Differential pressure – recording of indicator instrument with double switchable filter:

1. When the new cartridge is put into service, make the recording index (2) coincide with the pressure indicator (3) on the pressure indicator device (1);
2. Check the differential pressure as follows:
   • At full load or at rated engine power, read the pressure on the indicator instrument (1);
   • If the differential pressure between the indicator pointer (2) and the pressure indicator (3) is greater than or equal to 0.3 bar, wash the filter cartridge in service.

Drainage of the fuel pre-filter with double switchable filter:

1. Disable the filter to be drined (A) or (B) by turning the handle (7) towards the desired filter;
2. Loosen the vent valve (4) of the filter from which you wish to drain the condensate;
3. Open the drain valve (8) of the filter from which you wish to drain the condensate;
4. Drain the water and impurities from the filter until clean fuel comes out;
5. Close the drain valve (8) opened previously;
6. Connect the feed pump to the filling fitting (5) on the suction side of the filter;
7. Open the vent valve (4) and top up the fuel until fuel leaks from the vent pipe (6);
8. Close the vent valve (4);
9. Slightly turn the handle (7) (about 30°) and open the vent valve(s) (4), until fuel comes out of the vent pipe (6);
10. Close the vent valve (s) (4);
11. Turn the handle (7) to the deactivated drained filter position.

Rinsing of the fuel pre-filter with double switchable filter:

1. Disable the filter to be drained (A) or (B) by turning the handle (7) towards the desired filter;
2. Loosen the vent valve (4) of the filter to be rinsed;
3. Open the drain valve (8) and drain the fuel completely;
4. Close the drain valve (8) opened previously;
5. Close the vent valve (4).

Refilling of the fuel pre-filter with double switchable filter:

1. Turn off the engine making sure to prevent any unintentional ignition;
2. Connect the feed pump to the filling fitting (5) on the suction side of the filter;
3. Open the vent valve (4) and top up the fuel until fuel leaks from the vent pipe (6);
4. Close the vent valve (4);
5. Slightly turn the handle (7) (about 30°) and open the vent valve(s) (4), until fuel comes out of the vent pipe (6);
6. Close the vent valve (s) (4);
7. Turn the handle (7) to the deactivated drained filter position;
8. Check the differential pressure as follows:
   
   • At full load or at rated engine power, read the pressure on the indicator instrument (1);
   • If the differential pressure between the indicator pointer (2) and the pressure indicator (3) is greater than or equal to 0.3 bar, wash the filter cartridge in service.
9. If rinsing has not resulted in an improvement in differential pressure, replace the filter cartridge.

Replacing the fuel pre-filter cartridge with a switchable double filter:

1. Disable the filter to be drained (A) or (B) by turning the handle (6) towards the desired filter;
2. Loosen the vent valve (1) of the filter to be replaced;
3. Open the drain valve (5) and completely drain the fuel, water and impurities contained therein;
4. Close the drain valve (5);
5. Unscrew and remove the filter retaining screws (2);
6. Remove the elastic seal (3) and the filter cartridge (4);
7. Insert the new filter cartridge (4) and the elastic seal (3);
8. Refill the filter with clean fuel;
9. Replace the seal of the filter cover;
10. Place the filter under the cover and tighten the sealing screws (2);
11. Connect the disconnected filter;
12. Tighten the vent valve (1) after the fuel leaks;
13. Record the differential pressure indicator instrument as indicated above.