The new B Series track feller bunchers feature smoother hydraulic performance, increased engine HP, a more comfortable operator station and better right side operator visibility. The Cat 521B Series are zero tail swing machines designed for medium to high production clear cut and or select cut on rough terrain. These machines perform in a variety of small through larger tree size applications. A robust undercarriage utilizes proven components, customized for demanding forestry conditions. The unique boom design provides industry leading lift capacity throughout full reach range, a benefit in large timber.
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Powerful Performance
The Cat C9 electronically controlled ACERT engine delivers power while meeting all current U.S. EPA emission standards. All models contain a fuel/water separator, engine air intake heater and a dual-stage combination air cleaner with precleaner.
High Capacity Cooling System
The side-by-side radiator/oil cooler gives excellent cooling capacity for high production bunching and harvesting. On-demand Flexxaire fan activates only when required and allows the cooling fan to purge debris from the radiator area, keeping a cleaner cooling system. The IQAN control system automatically adjusts the Flexxaire fan blade angle, reducing horsepower demand and lowering fuel consumption. The purge cycle frequency and duration can be set by operator in the cab to suit varying application conditions.
Engine Oil
Cat engine oil is formulated to optimize engine life and performance and is recommended for use in Cat diesel engines. Extended oil change intervals reduce maintenance and machine downtime.
Service
The clamshell style engine compartment provides easy access to all filters, oil dipstick, coolant reservoir, hydraulic fill pump, valves and hoses reducing maintenance time.
Low Exhaust Emissions
The Cat C9 ACERT engine is a low emission engine designed to meet U.S. EPA emission regulations.
Batteries
An optional starting aid for colder climates is available for 521B machine models. This option provides two (2) additional batteries and HD battery cables.