Komatsu WA380-8, Operation & Maintenance Manual

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METHOD FOR REPLACING FUEL PREFILTER CARTRIDGE
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WARNING
• Just after the engine stops, all parts are still very hot, so do not replace the filter immediately. Wait
for all of parts to cool down before starting the work.
• High pressure is generated inside the engine fuel piping system when the engine is running.
When replacing the filter, wait for at least 30 seconds after stopping the engine to let the internal
pressure go down before replacing the filter.
• Do not bring any open flame close.
NOTICE
• Komatsu genuine fuel filter cartridges use a special filter that has highly efficient filtering ability.
When replacing 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 on the right side of the ma-
chine.
2.
Place a container under the fuel prefilter cartridge to catch
the fuel.
3.
Loosen drain valve (1) and drain water and sediments
from transparent cup (2), and also drain all the fuel from fil-
ter cartridge (3).
4.
Disconnect connector (4).
5.
Wrap connector (4) with a plastic bag, etc. so that fuel, oil
and water do not get onto the disconnected connector.
6.
Turn transparent cup (2) counterclockwise by using the filter wrench, and remove it.
Transparent cup (2) is used again.
7.
Turn filter cartridge (3) counterclockwise by using the filter wrench, and remove it.
8.
Install currently removed transparent cup (2) to the bottom of the new fuel prefilter cartridge.
At this time, be sure to replace O-ring (5) 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 (3), 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.
9.
Clean the filter head.
10. Fill the new filter cartridge with clean fuel.
MAINTENANCE PROCEDURE MAINTENANCE
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