Komatsu WA380-8, Operation & Maintenance Manual

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NOTICE
• The filter element needs to be replaced every 2000 hours. For details of the replacement procedure,
see “METHOD FOR REPLACING KCCV FILTER ELEMENT (4-62)”.
• Do not operate the engine without the KCCV filter element or use a filter element other than the Ko-
matsu genuine one.
If this is ignored, the engine sucks oil and foreign material which can cause a trouble.
Always install Komatsu genuine KCCV filter element.
• The filter element cannot be flushed. It is degraded in performance and can cause an engine trou-
ble, even if it is cleaned.
Never reuse the element.
HANDLE UREA SCR SYSTEM WARNING
Urea SCR system is a device which converts toxic nitrogen oxides (NOx) in the exhaust gas into harmless nitro-
gen and water. By spraying DEF into the exhaust gas, it decomposes and hydrolyzes to form ammonia (NH3)
and the ammonia selectively reacts with nitrogen oxides for the conversion to nitrogen and water.
The Komatsu Urea SCR System continuously monitors its operation conditions and stores information on inap-
propriate operations including malfunctions. The information is used for system diagnostics and also for Induce-
ment required by the authorities on engine systems that use Urea SCR systems. Inducement is intended for the
operator to take prompt actions to maintain and correct inappropriate behaviors of Urea SCR systems by utiliz-
ing visible and audible alerts , and engine power derate in addition. Alerts in Inducement of the Komatsu Urea
SCR System progresses step by step starting from visual indications on the machine monitor and audible
sounds to engine power derate to avoid getting into unsafe conditions.
The Komatsu Urea System also monitors recurrences of abnormalities of the system. Inducement in the recur-
rences is activated when another abnormality occurs within 40 hours after the first abnormality is fixed.
The Komatsu’s Urea is composed of two major systems, which are the DEF system and the SCR catalyst Ass’y.
DEF is supplied from DEF system into the exhaust system.
DEF system consist of DEF tank (1), DEF hose (2), DEF pump
(3), and DEF injector (4). SCR Ass’y is indicated by (5).
In the event that indications of potential degradation of nitrogen
oxides conversion efficiency are detected, the active regenera-
tion is triggered to rejuvenate Urea SCR system even if the
amount of soot accumulated in the KDPF has not reached to
the regeneration thresholds.
For details of Aftertreatment Devices Regeneration, see “HAN-
DLE Komatsu Diesel Particulate Filter (KDPF) (3-133)”.
k k
WARNING
Fill ONLY DEF into DEF tank. Foreign material in the DEF
system or urea deposits caused by evaporation may hin-
der operation of the devices.
EXPLANATION OF COMPONENTS OPERATION
3-142