Ryobi RBC-52 - User Manual

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OWNER’S OPERATING MANUAL

PETROL BRUSH CUTTER

MODEL RBC-52

KEEP THIS MANUAL FOR FUTURE REFERENCE

Your new petrol brush cutter/line trimmer has been engineered and manufactured to Ryobi’s high

standard of dependability, ease of operation and operator safety. Properly cared for, it will give you

years of rugged, trouble free performance. If you use your petrol brush cutter/line trimmer properly

and only for what it is intended, you will enjoy years of safe, reliable servi

ce.

SPECIFICATIONS

Engine type........................................................................................2-stroke, air-cooled

Engine displacement................................................................................................ 52cc

Engine max. speed........................................................................................... 9500min

-1

Engine idle speed...................................................................................3000+/-300min

-1

Clutch speed.................................................................................................... 4200min

-1

Fuel tank capacity................................................................................................. 1200ml

Fuel type................................................................ 25:1 of unleaded

petrol & 2 stroke oil

Starting system............................................................................................Recoil starter

Spark plug type.....................................................................................................L7T/LD

Cutting diameter (Brush Cutter)............................................................................25.5cm

Cutting diameter (Line Trimmer)......

........................................................................43cm

Cutting line size...................................................................................... Ø2.4mm x 2.5m

Sound pressure level (Brush Cutter).......................................... L

96.7dB(A),k=3dB(A)

Sound pressure level (Line Trimmer)......................................... L

94.4dB(A),k=3dB(A)

Sound power level (Brush Cutt

er)............................................L

112.9dB(A),k=3dB(A)

Sound power level (Line Trimmer)...........................................L

108.0dB(A),k=3dB(A)

Vibration level (Left handle) (Brush Cutter)........................................ 8.2m/s

, K=1.5m/s

Vibration level (Left handle) (Line Trimmer)..................................... 4.27m/s

, K=1.5m/s

Vibration level (Right handle) (Brush Cutter)....................................6.58m/s

, K=1.5m/s

Vibration level (Right handle) (Line Trimmer)...................................4.52m/s

, K=1.5m/s

Net weight................................................................................................................7.7kg

THANK YOU FOR BUYING A RYOBI

PETROL BRUSH CUTTER

CAUTION: Carefully read through this entire owner’s

manual, paying close attention to the general

safety rules and rules for safe operation,

before using.

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This document is the owner's operating manual for the RYOBI PETROL BRUSH CUTTER, MODEL RBC-52.

Function Description

The Ryobi Petrol Brush Cutter/Line Trimmer is designed for cutting grass, weeds, bush, and other undergrowth. It is not intended for other purposes such as edging or hedge cutting, as this may cause injury. The unit can be used with either a cutting line spool for trimming or a cutting blade for heavier brush. It is engineered for dependability, ease of operation, and operator safety, providing rugged, trouble-free performance when used properly.

Important Technical Specifications

The RBC-52 model features a 2-stroke, air-cooled engine with an engine displacement of 52 cc. Key performance specifications include:

Engine max. speed: 9500 min⁻¹
Engine idle speed: 3000 +/- 300 min⁻¹
Clutch speed: 4200 min⁻¹
Fuel tank capacity: 1200 ml
Fuel type: Requires a 25:1 mixture of unleaded petrol and 2-stroke oil. It is certified to operate on unleaded petrol with an octane rating of 87 ([R + M] / 2) or higher. Only synthetic 2-stroke oil should be used.
Starting system: Recoil starter
Spark plug type: L7T/LD
Cutting diameter (Brush Cutter): 25.5 cm
Cutting diameter (Line Trimmer): 43 cm
Cutting line size: Ø2.4 mm x 2.5 m

Noise and Vibration Levels:

Sound pressure level (Brush Cutter): L_pA 96.7 dB(A), k=3 dB(A)
Sound pressure level (Line Trimmer): L_pA 94.4 dB(A), k=3 dB(A)
Sound power level (Brush Cutter): L_WA 112.9 dB(A), k=3 dB(A)
Sound power level (Line Trimmer): L_WA 108.0 dB(A), k=3 dB(A)
Vibration level (Left handle) (Brush Cutter): 8.2 m/s², K=1.5 m/s²
Vibration level (Left handle) (Line Trimmer): 4.27 m/s², K=1.5 m/s²
Vibration level (Right handle) (Brush Cutter): 6.58 m/s², K=1.5 m/s²
Vibration level (Right handle) (Line Trimmer): 4.52 m/s², K=1.5 m/s²
Net weight: 7.7 kg

Usage Features

The brush cutter/line trimmer is designed for safe and efficient operation. Assembly:

U-Handle Assembly: The U-handle with controls is attached to the drive shaft using a mounting bracket. The handle with controls should be positioned for use with the right hand.
Grass Deflector: A grass deflector with a sharp line cutting blade must be securely attached to prevent injury from thrown debris and to cut the line to the correct length.
Drive Shaft Connection: The upper and lower drive shafts connect via a coupler device. It's crucial to ensure the clamp knob is fully tightened to lock the shafts in place.
Line Spool/Blade Fitting: The unit can be fitted with either a cutting line spool or a cutting blade. Both attachments use a left-hand thread for tightening (turn counter-clockwise). Special care, including thick safety gloves and correct tools, is advised when fitting the blade.
Harness: A shoulder harness is provided for comfortable operation, allowing the blade or cutter attachment to suspend between 100 mm to 300 mm above the ground. It features a quick-release tab for emergency situations.

Starting and Stopping:

Cold Engine Start: Move the On/Off switch to 'ON', push the primer bulb approximately ten times, set the choke lever to 'CLOSE' (UP), depress the safety lever and squeeze the throttle trigger fully, then pull the starter handle sharply (no more than 4 times). Once the engine attempts to start, set the choke lever to 'OPEN' (DOWN) and pull the starter handle until it runs (no more than 6 times).
Warm Engine Start: Move the On/Off switch to 'ON', push the primer bulb until fuel is visible, set the choke lever to 'CLOSE' (UP), depress the safety lever and squeeze the throttle trigger fully, then pull the starter cord.
Stopping: Release the throttle trigger to allow the engine to idle, then depress the Stop/Start switch to 'STOP'. Wait for the cutter blade to stop completely before contact with anything.

Operating Techniques:

Trimmer Use: Always position the machine on the operator's right side to avoid exposure to hot surfaces. Operate at full throttle, cutting tall grass from top down to prevent wrapping. Maintain a firm grip with both hands, holding the trigger handle at hip height.
Brush Cutter Use: Exercise extreme caution due to "blade thrust," a violent reaction when the blade contacts an un-cuttable object. Approach weeds from right to left to minimize this reaction. The blade is suited for pulpy weeds and vines, not woody brush or material over 13 mm (1/2 in.) diameter. Always wear the shoulder harness and adjust it for a comfortable operating position, keeping the blade away from the body and below waist level. Never operate with the blade 76 cm (30 in.) or more above ground.
Line Advancement: The cutting line can be advanced by tapping the knob on hard, bare ground while the engine runs at full throttle. If the line is too short, stop the engine and manually advance it by pushing the spool retainer down and pulling the lines.

Safety Precautions:

Always wear eye protection (ANSI Z87.1), hearing protection, heavy, long pants, boots, and gloves.
Keep bystanders, children, and pets at least 15 m (50 ft.) away.
Never operate when tired, ill, or under the influence of substances.
Do not operate in poor lighting.
Keep all body parts away from moving parts and hot surfaces.
Never start or run the engine in a closed or poorly ventilated area.
Clear the work area of objects like rocks, glass, nails, wire, or string before each use.
Fuel is highly flammable; handle with care, outdoors only, away from ignition sources.

Maintenance Features

Regular maintenance is essential for safe and efficient operation and to prolong the life of the product. General Maintenance:

Before each use, inspect for damaged, missing, or loose parts (screws, nuts, bolts, caps). Tighten all fasteners and replace any damaged parts.
Avoid using solvents on plastic parts; use clean cloths for cleaning.
Do not allow brake fluids, gasoline, petroleum-based products, or penetrating lubricants to contact plastic parts.

Fuel System:

Use only the recommended 25:1 unleaded petrol and synthetic 2-stroke oil mixture.
Mix fuel outdoors and in small quantities (usable within 30 days).
Clean around the fuel cap before filling to prevent contamination.
Stop the engine and allow it to cool before refueling.
Check for fuel leaks regularly; replace any leaking fuel cap, tank, or line immediately. The fuel cap contains a non-serviceable filter and check valve; replace the cap if performance issues arise from a clogged filter or faulty valve.

Air Filter:

Clean the air filter elements regularly to ensure clean air supply to the engine.
Remove the air filter cover, remove the foam filter element, wash with warm soapy water, rinse, and dry completely.
Apply a light coat of engine oil to the foam filter element and squeeze it out.
Replace the air filter, ensuring it is seated properly to prevent dirt from entering the engine. Replace damaged foam elements.

Spark Plug:

Do not remove the spark plug from a hot engine.
Clean or replace the spark plug if soiled with heavy oil deposits or if the center electrode is worn.
The engine uses an L7T/LD spark plug with a 0.6-0.7 mm electrode gap. Replace annually.
Be careful not to cross-thread the spark plug during reinstallation.

Exhaust Port and Muffler:

Carbon deposits can block the exhaust port, muffler, and/or spark arrestor screen, leading to power loss. Ryobi highly recommends that only qualified service technicians perform this service.

Spool Replacement:

The line diameter is Ø2.4 mm x 2.5 m.
To replace, stop the engine, disconnect the spark plug wire, hold the line head, push down the releasing tab, and unscrew the spool retaining cover counter-clockwise.
Remove the empty spool. When installing a new spool, ensure the two lines are captured in the slots and extended approximately 152 mm beyond each slot.
Thread the strings into the spool holes, push the spool into the line head, and then pull the strings sharply to release them from the slots. Screw on the spool retaining knob clockwise until securely fastened.

Idle Speed Adjustment:

If the cutting attachment turns at idle, the idle speed screw needs adjustment. Turn the idle speed screw counter-clockwise to reduce the idle RPM and stop the cutting attachment movement. If the attachment still moves at idle, discontinue use and contact customer support. Always wear protective clothing and keep bystanders 50 ft. away during adjustment.

Storage:

Drain all fuel from the tank into an approved container and run the engine until it stops.
Clean all foreign material from the unit.
Store in a well-ventilated place, inaccessible to children, and away from corrosive agents.