Komatsu GD555-5 Operation & Maintenance Manual page 306

MAINTENANCE MAINTENANCE
5. Remove hose (6) connected to drain plug (5).
6. Using a filter wrench, turn filter cartridge (3) counterclockwise
to remove it.
7. After removing the cartridge, turn cup (4) of the water separator
installed to the bottom of the cartridge counterclockwise. (This
cup is used again. If it is damaged, replace it with a new part.)
8. Install cup (4) to the bottom of the new fuel prefilter cartridge.
When doing this, always replace the seal ring with a new part.
Tightening torque for cup: 10 Nm {1.0 kgm}
When replacing the seal ring, coat the surface with clean fuel
before installing it.
9. Check that drain plug (5) at the bottom of cup (4) of the fuel
prefilter is tightened securely.
Tightening torque: 0.2 to 0.45 Nm {0.02 to 0.046 kgm, 0.1 to 0.3
lbft)}
10. Clean the filter holder.
NOTICE
When filling the filter cartridge with fuel, carry out the filling operation with
cap (A) fitted.
Cap (A) acts to prevent the entry of dirt or dust into the filter cartridge.
11. Fill the filter cartridge with clean fuel through the 8 small holes
(B) in the new filter cartridge.
12. Coat thinly the packing surface of the filter cartridge with clean
oil.
13. Remove filter cartridge cap (A) and install to the filter holder.
14. When installing, tighten until the packing surface contacts the seal surface of the filter holder, then tighten it 3/4
of a turn.
If the filter cartridge is tightened too far, the packing will be damaged and this will lead to leakage of fuel. If the
filter cartridge is too loose, fuel will also leak from the packing, so always tighten the correct amount.
When tightening with a filter wrench, be extremely careful not to dent or damage the filter.
15. Connect removed connector (1), clamp (2) and hose (6).
16. When replacing the standard fuel filter cartridge (every 1000 hours), replace the cartridge and bleed the air. For
details, see the items in "REPLACE FUEL MAIN FILTER CARTRIDGE (PAGE 4-63)".
17. Start the engine, check that there is no leakage of fuel from the filter seal surface or water separator mounting
surface, then run for approximately 10 minutes at low idle.
PROCEDURE FOR BLEEDING AIR
1. Fill the fuel tank with fuel.
2. Open the engine side cover on the left side of the machine.
3. Loosen and pull out feed pump knob (1) and move it forward
and backward.
The plug on the side surface of the fuel prefilter head does
not need to be removed.
Keep moving knob (1) until it becomes heavy.
4. After bleeding air, push in and tighten knob (1).
SERVICE PROCEDURE SERVICE PROCEDURE
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