Method For Replacing Def Filter - Komatsu H70051 Series Operation & Maintenance Manual

MAINTENANCE

METHOD FOR REPLACING DEF FILTER

Immediately after the engine is stopped, the parts are still very hot. Do not replace the filter immediately.
Wait until all of parts cool down before starting the work.
NOTICE
• Komatsu recommends using Komatsu genuine parts for replacement parts.
• If the machine is operated without DEF filter attached, or with the filter other than Komatsu genuine
parts, foreign materials may enter into DEF pump and DEF injector which will cause failure of the
machine. Never operate the machine without DEF filter attached, nor use the filter other than Komat-
su genuine parts.
• DEF filter cannot be flushed. Flushing or regenerating of it will degrade the performance of filter,
and will cause the breakage of DEF tank. Never reuse the DEF filter.
• Improper assembly of DEF filter may cause leakage of DEF. Replace the DEF filter in the correct pro-
cedure.
• DEF freezes at –11 °C. If it is frozen, replacement of the filter becomes difficult. Replace the filter
when the temperature around DEF pump is higher than -11 °C, and in the condition that DEF is not
frozen.
After the engine is stopped, DEF system devices automatically purge DEF in DEF injector and DEF pump and
return it to DEF tank to prevent malfunction of the devices caused by freezing of DEF or deposition of urea.
After the engine is stopped, the devices are operated for a few minutes. Before replacing the filter, clean around
the DEF pump first after DEF system devices stop.
Items to be prepared
• DEF filter removal tool
• Torque wrench
1.
Remove the bolts (1) (6 pieces) to remove cover (2).
The DEF filter is located at the positions shown in the fig-
ure.
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WARNING
MAINTENANCE PROCEDURE
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