Komatsu H75051 Operation & Maintenance Manual page 368

MAINTENANCE PROCEDURE
NOTICE
• When filling the filter cartridge with fuel, do not re-
move the cap (A) at the center. Always fill with fuel
from the small holes (B) (8 places) on the dirty
side.
• After filling with fuel, remove the cap (A) and in-
stall the fuel filter.
• Always fill with clean fuel. Be careful not to let any
dirt or dust get into the fuel. In particular, center
portion is the clean side, so do not remove the cap
(A) when filling with fuel. Be careful not to let dirt
or dust get into the center portion on the clean
side.
12. Thinly apply oil to the packing surface of the new filter cartridge, then install the filter cartridge to the filter
head.
NOTICE
• When installing the filter cartridge, tighten it 3/4 of a turn after the packing surface contacts the
seal surface of the filter head.
If the filter cartridge is tightened too much, the packing may be damaged and this will cause the
leakage of fuel. If it is not tightened enough, fuel will leak through the gap at packing. Be sure to
observe the tightening angle.
• When tightening with a filter wrench, be extremely careful not to dent or damage the filter.
13. Check that the drain valve (2) is tightened securely.
14. Install the clip (6) of sensor harness.
15. Remove the plastic bag wrapping the connector (5), then connect the connector (5).
REMARK
• If water gets on the connector (5), the sensor may
malfunction and the water separator caution lamp may
flash. When removing the connector (5), be extremely
careful not to let water get on the connector.
• If water gets on the connector (5), dry it completely
before connecting it.
16. After completing the replacement of the filter cartridge (4),
bleed air from the circuit.
Bleed the air as follows.
1)
Fill up the fuel tank with fuel (to the level where the
float is at the highest position).
2)
Loosen the knob of feed pump (8), pull it out once, then pump it in and out until the movement be-
comes heavy.
REMARK
It is not necessary to remove the plugs at the fuel prefilter head and at the fuel main filter head.
When the engine runs out of fuel, use the same procedure to operate the feed pump (8) and bleed the air.
17. After bleeding air, push in the knob of feed pump (8) and tighten it.
18. After replacing the filter cartridge, start the engine and run it at low idle for 10 minutes.
19. Check the filter seal surface and the mounting face of the transparent cup for fuel leakage.
If there is any leakage of fuel, check the tightening condition of the filter cartridge.
If there is still fuel leakage, perform the steps 1 to 8 to remove the filter cartridge, and if any damage or
pinched foreign material on the packing surface is found, replace it with a new cartridge and repeat the
steps 9 to 19.
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MAINTENANCE