The government has introduced standards to reduce air pollution from diesel engines, and they have done so in stages, or “Tiers”. The tiers depend on engine horsepower and year of engine production. The main goal is to reduce exhaust emissions of black smoke and nitrogen oxides that contribute to smog. Tier four is the final tier to be met for this standardization system.
There has been concern from consumers that the tier four engines will not perform as well as previous models, but the truth is quite the opposite. Kubota has ensured that their tier four engines will perform and, in some cases outperform previous tier models.
Kubota is implementing different solutions for different engine sizes, applications, and emission tiers. For example, small engines under 25 horsepower can comply with Tier 4 through Kubota’s design and efficient control of the combustion process, without the need of exhaust filters, catalysts or exhaust additives.
Emissions Information Summary
• The EPA has mandated that diesel engines become cleaner, so they have introduced standards for all engine manufacturers.
• Kubota is fully compliant and has chosen appropriate technologies to meet the standards.
• For most engines, a diesel particulate filter is used to reduce soot emissions.
• The DPF replaces the standard muffler and is located in about the same place.
• The accumulated soot must be removed (burned) approximately every 15 to 20 hours, in a process called “Regeneration”. The actual time depends on operating conditions.
• Kubota recommends Automatic Regeneration if the equipment is used outdoors and in a non combustible environment.
• The engine RPM must be raised to enable regeneration.
• If the operator does not enable regeneration in due time, a dealer service call may be necessary.
• When regeneration is underway, a small amount of white smoke may be observed emitting from the exhaust pipe.
• During regeneration, the exhaust temperature will rise. Therefore, regeneration should only take place when the machine is in a non combustible area.
