OPERATOR’S MANUAL CSP3816 - UT74123A - 406 mm 16 in. 38cc Chainsaw CSP4518 - UT74125A - 457 mm 18 in. 45cc Chainsaw CSP4520 - UT74127A - 508 mm 20 in. 45cc Chainsaw Your new chainsaw has been engineered and manufactured to Homelite’s high standard for dependability, ease of operation and operator safety. Properly cared for, it will give you years of rugged, trouble-free performance. WARNING: To reduce the risk of injury, the user must read and understand the operator’s manual.
TABLE OF CONTENTS Q Introduction ..................................................................................................................................................................... 2 Q General Safety Rules ................................................................................................................................................... 3-4 Q Specific Safety Rules ................................................................................................................
GENERAL SAFETY RULES WARNING: The warnings, labels and instructions found in this section of the operator’s manual are for your safety. Failure to follow all instructions may result in serious personal injury. Safe operation of this tool requires that you read and understand this operator’s manual and all labels affixed to the tool. Safety is a combination of using common sense, staying alert, and knowing how your saw works. READ ALL INSTRUCTIONS Q KNOW YOUR TOOL. Read the operator’s manual carefully.
GENERAL SAFETY RULES Q KEEP ALL PARTS OF YOUR BODY away from the saw chain when the engine is running. Q ALWAYS CARRY THE CHAINSAW WITH THE ENGINE STOPPED AND THE BRAKE ENGAGED, the guide bar and saw chain to the rear, and the silencer away from your body. When transporting the chainsaw, use the appropriate guide bar scabbard. Q DO NOT OPERATE A CHAINSAW THAT IS DAMAGED, improperly adjusted, or not completely and securely assembled.
SPECIFIC SAFETY RULES WARNING: The warnings, labels and instructions found in this section of the operator’s manual are for your safety. Failure to follow all instructions may result in serious personal injury. GENERAL PRECAUTIONS Q DO NOT CUT VINES and/or small underbrush less than 76 mm (3 in.) in diameter. Q SILENCER SURFACES ARE VERY HOT during and after operation of the chainsaw; keep all body parts away from the silencer. Serious burns may occur if contact is made with the silencer.
SPECIFIC SAFETY RULES PUSH AND PULL MAINTENANCE PRECAUTIONS The reaction force is always opposite to the direction the chain is moving. Thus, the operator must be ready to control the PULL when cutting on the bottom edge of the bar and the PUSH when cutting along the top edge. Never operate a chainsaw that is damaged, improperly adjusted, or not completely and securely assembled. Be sure that the saw chain stops moving when the throttle control trigger is released.
SYMBOLS Important: Some of the following symbols may be used on your tool. Please study them and learn their meaning. Proper interpretation of these symbols will allow you to operate the tool better and more safely. SYMBOL NAME Safety Alert Symbol Indicates danger, warning or caution. It means attention!!! Your safety is involved.
SYMBOLS No Smoking Do not smoke when mixing fuel or filling fuel tank. Petrol Use unleaded petrol intended for motor vehicle use with an octane rating of 87 [R + M] / 2) or higher. Oil Use 2-cycle oil for air-cooled engines. Mix Petrol and Oil Mix the fuel mix thoroughly and also each time before refuelling.
SPECIFICATIONS Weight - No bar, chain, fuel or oil .............................................................................................................................. 4.4 kg Fuel tank capacity ................................................................................................................................................. 575 cm3 Oil tank capacity ........................................................................................................................................
FEATURES TRIGGER RELEASE SILENCER CHAIN OIL CAP FRONT HAND GUARD/ CHAIN BRAKE FRONT HANDLE SAFE-T-TIP ® CYLINDER COVER CHAIN CATCHER CHOKE LEVER PRIMER BULB CARBURETTOR ADJUSTMENT STARTER GRIP REAR HANDLE STARTER/FAN HOUSING STOP ON/OFF SWITCH FUEL MIX CAP UK - Page 10 THROTTLE TRIGGER Fig.
OPERATION For your safety, study this entire manual before operating the saw. Pay particular attention to the precautions and instructions listed in the operator’s manual. WEAR HEAD PROTECTION SAFE-T-TIP WEAR EYE PROTECTION Fig.
OPERATION CHAIN BRAKE Chain brakes are designed to quickly stop the chain from rotating. When the chain brake lever/hand guard is pushed towards the bar, the chain should stop immediately. A chain brake does not prevent kick-back. The chain brake should be cleaned and tested daily. Refer to “Operation” later in this manual for additional information. WARNING: Even with daily cleaning of the mechanism, the dependability of a chain brake to perform under field conditions cannot be certified.
OPERATION WARNING: Always turn off engine before refuelling. Never add fuel to a machine with a running or hot engine. Move at least 9 m (25 ft.) from refuelling site before starting the engine. DO NOT SMOKE! Failure to heed this warning may result in possible personal injury. Q Mix 2% oil into the petrol. This is a 50:1 ratio. Q Mix the fuel thoroughly and each time before refuelling. Q Mix in small quantities. Do not mix quantities larger than usable in a 30-day period.
OPERATION STARTING THE ENGINE WARNING: Keep your body to the left of the chain line. Never straddle the saw or chain, or lean over past the chain line. STOP 1. Place the chainsaw on level ground and ensure that no objects or obstructions which could come in contact with the bar and chain are in the immediate vicinity. Fig. 8 ADDING OIL 2. Hold the front handle firmly with the left hand and put your right foot onto the base of the rear handle. See Figure 10. Use HOMELITE Bar and Chain Oil.
OPERATION STARTING A COLD ENGINE: 3. Move the chain brake to the BRAKE position. NOTE: Set the chain brake by pushing the chain brake lever/hand guard forward (towards the bar) to the brake position. Refer to “Operation – Operating Chain Brake” for additional information. 4. Set the ignition switch to the RUN (I) position. 5. Fully press and release the PRIMER BULB 7 times. 6. Pull CHOKE lever all the way OUT to full position.
OPERATION 7. Pull STARTER until engine attempts to start. Slowly pull the starter grip out for a short distance until you feel the starter engage, then briskly pull straight up. Do not pull to the end of the rope; this may damage the starter. Hold onto the grip during rewinding—see figure 16. Pull the starter rope until the first firing of the engine is heard (no more than five pulls). NOTE: A new unit may require additional pulls. 8. Push CHOKE lever all the way IN. 9. Pull STARTER until engine runs.
OPERATION PREPARING FOR CUTTING PROPER GRIP ON HANDLES Refer to “Specific Safety Rules – Safety Apparel” earlier in this manual for appropriate safety equipment. Q Wear non-slip gloves for maximum grip and protection. Q Hold the saw firmly with both hands. Always keep your LEFT HAND on the front handle and your RIGHT HAND on the rear handle, so that your body is to the left of the chain line.
OPERATION BASIC OPERATING/CUTTING PROCEDURES ADJUSTING THE CARBURETTOR Practise cutting a few small logs using the following technique, to get the “feel” of using your saw before you begin a major sawing operation. Before adjusting the carburettor, clean the air filter and the starter cover vents. Allow the engine to warm up before carburettor adjustment. Refer to “Maintenance” later in this manual. 1. Take the proper stance in front of the wood with the saw idling. 2.
OPERATION ADJUSTING IDLING SPEED OPERATING THE CHAIN BRAKE Q If the engine starts, runs, and accelerates but will not idle, turn the idling speed screw “ T ” clockwise to increase idling speed. Q If the chain turns at idle, turn the idling speed screw “ T ” anticlockwise to reduce the idling RPM and stop the chain movement. If the saw chain still moves at idling speed, contact a Homelite service dealer for adjustment and discontinue use until the repair is made.
OPERATION FELLING TREES HAZARDOUS CONDITIONS STAY AWAY FROM ELECTRICAL LINES AND BUILDINGS See Figure 29. WARNING: Do not fell trees during periods of high wind or heavy precipitation. Wait until the hazardous weather has ended. When felling a tree, it is important that you heed the following warnings to prevent possible serious injury. Q Wear eye, hearing and head protection when operating this equipment.
OPERATION PROPER PROCEDURE FOR TREE FELLING See Figure 30. 1. Pick your escape route (or routes in case the intended route is blocked). Clear the immediate area round the tree and make sure there are no obstructions in your planned path of retreat. Clear the path of safe retreat approximately 135° from the planned line of fall. PLANNED LINE OF FALL 2. Consider the force and direction of the wind, the lean and balance of the tree and the location of large limbs.
OPERATION 3. Cut a notch about one-third the diameter of the trunk in the side of the tree. Make the notch cuts so they intersect at right angles to the line of fall. This notch should be cleaned out to leave a straight line. To keep the weight of the wood off the saw, always make the lower cut of the notch before the upper cut. See Figure 31. 4. Make the back-cut level and horizontal, and at a minimum of 5 cm (2 in) above the horizontal cut of the notch. See Figure 31. NOTE: Never cut through to the notch.
OPERATION REMOVING BUTTRESS ROOTS A buttress root is a large root extending from the trunk of the tree above the ground. Remove large buttress roots before felling. Make the horizontal cut into the buttress first, followed by the vertical cut. Remove the resulting loose section from the work area. Follow the correct tree felling procedure after you have removed the large buttress roots. Refer to “Operation – Proper Procedure for Felling Trees” earlier in this manual.
OPERATION BUCKING LOGS UNDER STRESS Make the first bucking cut one-third of the way through the log and finish with a two-thirds cut on the opposite side. As you cut the log, it will tend to bend. The saw may become pinched or hung in the log if you make the first cut deeper than a third of the diameter of the log. LOG SUPPORTED AT ONE END FINISHING CUT LOAD Give special attention to logs under stress to prevent the bar and chain from pinching. OVER-BUCKING See Figure 38.
OPERATION LIMBING AND PRUNING Q Work slowly, keeping both hands on the saw with a firm grip. Maintain secure footing and balance. Q Keep the tree between you and the chain while limbing. Cut from the side of the tree opposite the branch you are cutting. LOAD Q Do not cut from a ladder; this is extremely dangerous. Leave this operation for professionals. Q Do not cut above chest height, as a saw held higher is difficult to control against kick-back.
MAINTENANCE ASSEMBLING THE BAR AND CHAIN See Figures 41 through 47. DANGER: Never start the engine before installing the guide bar, chain, drive case cover and clutch drum. Without all these parts in place, the clutch may fly off or explode, exposing the user to possible serious injury. COMBINATION WRENCH WARNING: To avoid serious personal injury, read and understand all the safety instructions in this section. BAR MOUNTING NUTS Fig. 42 1.
MAINTENANCE 6. Lay out the saw chain in a loop and straighten any kinks. The cutters should face in the direction of chain rotation. If they face backwards, turn the loop over. See Figure 45. 7. Place the chain drive links into the bar groove as shown in figure 46. BAR GROOVE 8. Position the chain so there is a loop at the back of the bar. 9. Hold the chain in position on the bar and place the loop round the sprocket. 10.
MAINTENANCE 11. Replace the outer guide bar plate, ensuring that the bar pin groove is at the bottom with the upper and lower edges angled away from the guide bar. 12. Replace the clutch cover and bar mounting nuts. 13. Tighten the bar mounting nuts finger tight only. The bar must be free to move for tension adjustment. 14. Remove all slack from the chain by turning the chain tensioning screw clockwise until the chain seats snugly against the bar with the drive links in the bar groove. 15.
MAINTENANCE ADJUSTING THE CHAIN TENSION WARNING: Never touch or adjust the chain while the motor is running. The saw chain is very sharp. Always wear protective gloves when performing maintenance on the chain. 1. Stop the engine before setting the chain tension. APPROXIMATELY 1.25 mm 2. Make sure the guide bar nuts are loosened to finger tight and turn the chain tensioner clockwise to tension the chain.
MAINTENANCE SHARPENING THE CUTTERS Q Raker depth gauge) clearance. See Figure 55. 1. Too low increases the potential for kick-back. 2. Not low enough decreases cutting ability. Q If the cutter teeth hit hard objects such as nails and stones, or are abraded by mud or sand on the wood, let the Homelite service dealer sharpen the chain. NOTE: Inspect the drive sprocket for wear or damage when replacing the chain.
MAINTENANCE CHECK FOR WEAR OR DAMAGE LEFT-HAND CUTTERS RIGHT-HAND CUTTERS Fig. 62 Fig. 59 CAUTION: A dull or improperly sharpened chain can cause excessive engine speed during cutting, which may result in severe engine damage. WARNING: Improper chain sharpening increases the potential of kick-back. Fig. 60 WARNING: Failure to replace or repair a damaged chain may cause serious injury. WARNING: The saw chain is very sharp. Always wear protective gloves when performing maintenance to the chain. Fig.
MAINTENANCE TOP PLATE FILING ANGLE SIDE PLATE FILING ANGLE Q CORRECT 30° – file holders are marked with guide marks to align file properly to produce correct top plate angle. Q LESS THAN 30° – for cross cutting. 80° Q MORE THAN 30° – feathered edge dulls quickly. CORRECT SIDE PLATE ANGLE Q CORRECT 80o – Produced automatically if you use the correct diameter file in the file holder. Q HOOK – “Grabs” and dulls quickly, increases the potential of KICK-BACK.
MAINTENANCE MAINTAINING THE SAFE-T-TIP® NOSE GUARD RESTORE ORIGINAL SHAPE BY ROUNDING THE FRONT CAUTION: Make sure the chain has stopped before you do any work on the saw. WARNING: Fig. 67 Although the guide bar comes with a SAFE-T-TIP® antikick-back device already installed, be sure to check the tightness of the mounting screw before each use. MAINTAINING THE GUIDE BAR CAUTION: Make sure the chain has stopped before you do any work on the saw.
MAINTENANCE Q Clean the pre-filter every 25 tanks of fuel or sooner, if required. Remove the cylinder cover, starter assembly and the fan housing baffle for access to the pre-filter in the engine housing. TIGHTEN 3/4 OF A TURN NOTE: If you use an air hose for drying, blow through both sides of filter. CAUTION: Fig. 70 MOUNTING THE SAFE-T-TIP® NOSE GUARD See Figure 70. Never run the engine without the air filter; serious damage could result.
MAINTENANCE CLEANING THE STARTER UNIT Use a brush or compressed air to keep the cooling vents of the starter assembly free and clean of debris. CLEAN FLYWHEEL FINS P STO Fig. 76 CHECKING THE FUEL FILTER Fig. 74 Check the fuel filter periodically. Replace it if contaminated or damaged. CLEANING THE ENGINE Clean the cylinder fins and flywheel fins with compressed air or a brush periodically. Dangerous overheating of the engine may occur due to impurities on the cylinder.
MAINTENANCE CLEANING THE SPARK ARRESTING SILENCER CHAIN CATCHER The silencer is equipped with a spark arrester screen. A faulty spark arrester screen may create a fire hazard. Through normal use the screen becomes dirty and should be inspected weekly and cleaned as required. Always keep the silencer and spark arrester on your saw in good condition. WARNING Silencer surfaces are very hot during and after operation of the chainsaw. Keep all body parts away from the silencer.
BAR AND CHAIN COMBINATIONS Length of Bar Guide Bar Part Number Chain Part Number 305 mm (12 in.) UP08695 UP08692 356 mm (14 in.) UP08696 UP08693 406 mm (16 in.) UP08698 UP08694 TROUBLESHOOTING PROBLEM Engine will not start. Make sure ignition switch is in start position (“I”). POSSIBLE CAUSE SOLUTION 1. Check spark. Remove air filter cover. Remove sparking plug from cylinder.
TROUBLESHOOTING PROBLEM POSSIBLE CAUSE Engine starts, runs, and accelerates but will not idle. Carburettor requires adjustment. Turn idling speed screw “T” clockwise to increase idling speed. If chain turns at idle, turn idling speed screw “T” anticlockwise to decrease speed. Wear protective equipment and observe all safety instructions. See Figure 82. Bar and chain running hot and smoking. 1. Chain oil tank empty. 1. Oil tank should be filled every time that fuel tank is filled. 2.
WARRANTY GUARANTEE – STATEMENT RTSA / RTUK / RTG) All Homelite products are guaranteed from defects in material and workmanship, for a period of twenty-four (24) months, effective and evidenced from date of original invoice or delivery note. Defects caused by normal wear and tear, unauthorised/improper maintenance/handling or overload are excluded from this guarantee, as are accessories such as battery packs, bulbs, blades and bits etc.
OPERATOR’S MANUAL CSP3816 - UT74123A - 406 mm 16 in. 38cc Chainsaw CSP4518 - UT74125A - 457 mm 18 in. 45cc Chainsaw CSP4520 - UT74127A - 508 mm 20 in. 45cc Chainsaw Ryobi Technologies GmbH Itterpark 7 D-40724 Hilden Germany Tel.: +49 0)2103 / 29 58 0 Fax : +49 0)2103 / 29 58 29 info@ryobi-rtg.de Ryobi Technologies Customer Services Anvil House Tuns Lane Henley-on-Thames RG9 1SA UK Homelite / R.T.S.