Komatsu H75051 Operation & Maintenance Manual page 367

MAINTENANCE
NOTICE
• Komatsu genuine fuel filter cartridges use a special filter that has highly efficient filtering ability.
When replacing the parts, Komatsu recommends using Komatsu genuine parts.
• The common rail fuel injection system used on this machine consists of more precise parts than
those in the conventional injection pump and nozzles. If any cartridge other than a Komatsu genu-
ine filter cartridge is used, dust or dirt may get in and cause problems with the injection system.
Never use a substitute.
• When performing inspection and maintenance of the fuel system, be careful not to let any foreign
material get in, more than ever before. If dust sticks to the fuel system, wash it off thoroughly with
fuel.
Items to be prepared
• Container to catch the drained fuel
• Filter wrench
When replacing the fuel main filter cartridge (every 1000 hours), replace the fuel prefilter cartridge first.
1.
Open the engine side cover (1) on the right side of the ma-
chine.
2.
Place a container under the fuel prefilter cartridge to re-
ceive the fuel.
3.
Loosen the drain valve (2) and drain the water and sedi-
ments from transparent cup (3), and also drain all the fuel
from filter cartridge (4).
4.
Disconnect the connector (5).
5.
Wrap the connector (5) with a plastic bag, etc. so that fuel,
oil and water do not get onto the disconnected connector.
6.
Remove the clip (6) of sensor harness.
7.
Turn the transparent cup (3) counterclockwise by using the
filter wrench, and remove it.
Transparent cup (3) is used again.
8.
Turn the filter cartridge (4) counterclockwise by using the filter wrench, and remove it.
9.
Install the currently removed transparent cup (3) to the bottom of the new fuel prefilter cartridge.
At this time, be sure to replace the O-ring (7) with a new one.
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.
MAINTENANCE PROCEDURE
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