Every 1000 Hours Maintenance; Method For Replacing Fuel Main Filter Cartridge - Komatsu H70051 Series Operation & Maintenance Manual

MAINTENANCE
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.
REMARK
When bleeding air, air may remain inside of the water separator. However, the engine can be started after
pumping the feed pump (8) in and out until it becomes heavy. Leave it as it is for a while after stopping the
engine, and air is bled spontaneously.

EVERY 1000 HOURS MAINTENANCE

Maintenance for every 50, 100, 250 and 500 hours service should be performed at the same time.

METHOD FOR REPLACING FUEL MAIN FILTER CARTRIDGE

• Immediately after the engine is stopped, the parts are still very hot. Do not replace the filter immedi-
ately. 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.
• After removing the filter cartridge, fuel drops fall down from the filter head.
In order to prevent outflow of the fuel, be sure not to leave the machine while the filter cartridge is
being removed.
Items to be prepared
• Container to catch the drained fuel
• Filter wrench
After replacing the fuel prefilter cartridge, replace the fuel main filter cartridge.
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WARNING
MAINTENANCE PROCEDURE
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