Tier IV Technology

Komatsu Diesel Particulate Filter (KDPF)

What is it?
Komatsu engines are designed with an integrated KDPF, a dual-action device consisting
of a Komatsu Diesel Oxidation Catalyst (KDOC) and Komatsu Catalyzed Soot Filter
(KCSF). The KDPF removes soot through "regeneration," a process that collects
inorganic materials that form during engine combustion.

Which pollutants does it address?
A complex mixture of solid and liquid particles, particulates are materials that are not
burned up during fuel combustion. They can include carbon, soot, sulfates, nitrates,
ammonium, various metals, and much more, all suspended in the air. KDPF essentially
captures these particles before they can escape into the atmosphere.

Maintenance tips
Recommended service intervals for KDPF are 4,500 hours and 9,000 hours.

Selective Catalytic Reduction (SCR) and Diesel Exhaust Fluid (DEF)

What is it?
SCR is an advanced active emissions control feature which injects DEF into the diesel
engine’s exhaust stream, breaking down potentially harmful NO_x into nontoxic water
(H₂O) and nitrogen gas (N₂).

Which pollutants does it address?
Nitrogen oxides (NO_x), a natural byproduct from fuel combustion, are not hazardous at
typical ambient concentrations. However, concentrated amounts can contribute to smog
and acid rain. In a cramped space, NO_x mixed with oxygen in the air creates nitrogen
dioxide (NO₂), an irritant gas that can cause inflammation of the airways.

Maintenance tips
Check DEF level on a regular basis, just as you do fuel levels. Komatsu equipment
continuously displays the DEF level gauge on the right side of the monitor screen. The
DEF low level indicator will alert you as a reminder to refill.

DEF storage guidelines
Diesel exhaust fluid should always be stored out of direct sunlight, and the temperature
must be above 32°F and below 86°F. Keep DEF in a plastic or stainless steel container,
as it can rust raw steel containers, ruining both the fluid and the container.

Heavy Duty Cooled Exhaust Gas Recirculation (CEGR) System

What is it?
CEGR reduces fuel consumption, lowers combustion temperatures, and decreases
emissions by circulating portions of the exhaust gas into the air intake.

Which pollutants does it address?
The system reduces NO_x and traps particulates in the diesel particulate filter (DPF).

Maintenance tips
CEGR machines generally require passive and manual regeneration cycles: cycles that
heat the diesel particular filter hot enough to burn off particulates.

Many Komatsu machines perform passive regen periodically during normal operation.

Manual regeneration may also be required, depending on the operation and machine
guidelines. Machines should be checked before operation. Check the operator's manual
for specific guidelines.

Komatsu Variable Geometry Turbocharger (KVGT) System

What is it?
The KVGT system uses hydraulic pressure to control how much air is fed into the engine.
Using the machine's control system, the KVGT delivers precise exhaust temperatures for
regeneration, a process that also reduces soot in the engine’s cylinders.

Which pollutant does it address?
NO_x

Maintenance tips
Consult your operator's manual. Follow recommended guidelines when replacing engine
oil and air filters to maintain KVGT efficiency. A clogged air filter will reduce air flow and
can result in excessive smoke, increased oil consumption, and low machine power.

Heavy Duty High Pressure Common Rail (HPCR) Fuel Injection System

What is it?
The HPCR system utilizes computer controls to ensure the proper injection of high
pressure fuel. Building on the technology found in previous Komatsu engines, the
improved HPCR system uses higher pressure injection to reduce particulates and lower
fuel consumption.

Which pollutants does it address?
NO_x and particulates

Maintenance tips
Water can wreak havoc on your HPCR system, so check your fuel filters and water
separators often to prevent water accumulation in the fuel tank.

Contact Your Local Representative for Details