Komatsu H70051 Series Operation & Maintenance Manual page 368

MAINTENANCE PROCEDURE
NOTICE
When installing the transparent cup, thinly apply oil to the packing surface, contact it to the sealing
surface of filter cartridge (4), and then tighten it 1/4 to 1/2 turn.
If the transparent cup is tightened too much, O-ring may be damaged, and this will cause the leak-
age of fuel. If it is not tightened enough, fuel will leak through the gap at O-ring. Be sure to observe
the tightening angle.
10. Clean the filter head.
11. Fill the new filter cartridge with clean fuel.
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.
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MAINTENANCE