Komatsu PC290LC-11 Operation & Maintenance Manual page 413

MAINTENANCE
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
The DEF filter is located at the positions shown in the figure on
the right.
1.
Remove filter cap (1) at the bottom of DEF pump, and re-
move equalizing element (2).
2.
Turn cap (4) of filter removal tool (3) and remove it.
3.
Check the installation of spacer (5).
4.
Insert filter removal tool (3) into the bottom of the DEF
pump and thrust in with hand.
MAINTENANCE PROCEDURE
4-71