This document is an owner's/operator's manual for a Bad Boy Professional String Trimmer, available in models ST225, ST254, and ST300T. The manual provides instructions for operation, maintenance, and safety, along with technical specifications and warranty information.

Function Description:

The Bad Boy Professional String Trimmer is a gas-powered handheld tool designed for cutting grass and light vegetation. It functions as a "Recortadora" in Spanish and "Coupe-bordures" in French, indicating its primary use for trimming and edging. The device utilizes a rotating string or line to cut, powered by a small internal combustion engine.

Important Technical Specifications:

The manual provides detailed specifications for the three models: ST225, ST254, and ST300T.

Weight (dry without fuel, debris shield, and cutting head):
- ST225: 11.3 lbs (5.1 kg)
- ST254: 11.7 lbs (5.3 kg)
- ST300T: 12.2 lbs (5.6 kg)
Engine Displacement (cm³):
- ST225: 22.5
- ST254: 25.4
- ST300T: 30.1
Anti Vibration: Dual isolation-grip and engine mount for all models.
Carburetor: Walbro Diaphragm Type for all models.
Ignition System: Solid State for all models.
Fuel Tank Capacity (qts.):
- ST225: 0.53 qts (0.5L)
- ST254: 0.63 qts (0.6L)
- ST300T: 0.63 qts (0.6L)
Gas to Oil Ratio: 50:1 for all models.
Spark Plug: NGK BPM8Y for all models.
Spark Plug Gap (in.): .024-.028 (0.6-0.7mm) for all models.

The engine is a two-stroke type, requiring a specific gas-to-oil mixture (50:1). The manual emphasizes the use of high-performance, air-cooled, two-stroke engine oil and recommends regular unleaded gasoline with an octane rating of 89 or higher.

Usage Features:

The string trimmer is designed for ease of use with several operational features:

Assembly: The manual details the installation of the loop handle, shaft assembly, bottom clamp, debris shield, and trimmer head. Specific instructions are provided for left-hand and right-hand thread attachments for the trimmer head, depending on the model.
Fueling: Users are instructed on how to properly mix gasoline and two-stroke oil, fill the fuel tank, and avoid spills. Safety warnings regarding highly flammable fuel are prominently displayed.
Starting and Stopping: The starting procedure involves filling the fuel tank, resting the trimmer on the ground, making sure the cutting attachment is clear, and pulling the starter grip. Cold starting requires setting the choke lever to the closed position and then moving it to the high-speed position after a few pulls. Hot starting involves pulling the starter grip directly. Stopping the engine is achieved by releasing the throttle lever and pushing the stop switch.
Throttle Control: The device features a throttle lever with low speed, high speed, and a fast-idle lock button for controlled operation.
Trimmer Operation: The manual provides guidelines for safe and effective cutting, including maintaining a 3-inch (7.6 cm) distance from the ground for optimal cutting, scaling unwanted vegetation, and moving the trimmer in a side-to-side motion. It also illustrates correct and incorrect cutting techniques.
Safety Decals: The manual includes images and explanations of safety decals, such as warnings for thrown objects, hot surfaces, and rotating parts, to ensure user awareness of potential hazards.

Maintenance Features:

Regular maintenance is crucial for the longevity and safe operation of the string trimmer. The manual outlines a comprehensive maintenance schedule:

Daily/Every 25 hours/Every 50 hours/Every 100 hours: A checklist is provided for various maintenance tasks.
Muffler Maintenance: The muffler should be inspected and cleaned after every 100 hours of use. This involves removing the air filter cover, spark plug boot, cylinder cover, and then cleaning the tail, gasket, and spark arrester screen with a safety solvent and stiff brush. Replacement is necessary if parts cannot be thoroughly cleaned or are damaged.
Gearcase Maintenance: The gearcase should be checked for lubrication after each 30 hours of use. This involves removing the cutting attachment and boss adapter, cleaning the area, and removing the grease plug to add lithium-base bearing lube until the gearcase is full.
Air Filter Maintenance: The air filter should be cleaned daily or more often in dusty conditions. This involves loosening the knob, removing the air filter cover, cleaning the foam element and filter screen with warm, soapy water, and applying a light coat of motor oil to the foam element before reassembly.
Fuel Filter Maintenance: The fuel filter should be replaced after every 100 hours of operation. This involves draining the fuel tank, removing the fuel tank cap, and using a wire hook to pull out the fuel pick-up hose and fuel filter for replacement.
Spark Plug Maintenance: The spark plug should be removed and checked after every 100 hours of operation. This includes cleaning the electrodes with a stiff brush, adjusting the gap, and replacing the plug if it is oil-fouled, damaged, or if the electrodes are worn. The manual specifies a spark plug gap of .024-.028 inches (0.6-0.7 mm).
Cylinder Cooling Fins Maintenance: The cylinder cooling fins should be cleaned every 25 hours of operation or every 2-3 weeks to prevent overheating. This involves removing the air filter cover, spark plug boot, cylinder cover, and then cleaning dirt and debris from the cooling fins and around the cylinder base.
Spark Arrester Maintenance: The spark arrester should be inspected and cleaned after every 25 hours of use. This involves removing the air filter cover, spark plug boot, cylinder cover, and then cleaning the tail, gasket, and spark arrester with a safety solvent and stiff brush. Replacement is necessary if parts cannot be thoroughly cleaned or are damaged.

Warranty Information:

Bad Boy offers a limited warranty statement:

1 year for residential use.
2 years for commercial use.
90 days for rental use. The warranty covers defects in material and workmanship from the date of purchase. It explicitly states that the warranty does not cover maintenance items, shipping, handling, travel, payment for lost time, or any inconvenience and storage. Alterations, abuse, neglect, misuse, negligence, improper fuels, lubricants, fuel mixtures, or failure to operate or maintain the product in accordance with instructions approved by Bad Boy will void the warranty.

Emission Control Warranty:

The U.S. Environmental Protection Agency (EPA) and Maruyama Manufacturing Company, Inc. provide an emission control system warranty for small off-road engines. This warranty covers defects in materials and workmanship that cause the engine to fail to conform with applicable regulations for a period of 5 years from the date of sale to the ultimate purchaser. The emission control system warranty period for the time listed above, provided there has been no abuse, neglect, or improper maintenance of your small off-road engine, is 300 hours. This warranty covers components such as the carburetor or fuel injection system, ignition system, and catalytic converter, as well as hoses, belts, and connectors.

Bad Boy ST225 - Page 39

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