Ryobi RY34421 Operator's Manual - Page 16

MAINTENANCE  Insert the lines into the eyelets located on the sides of the string head. Line should be pushed in until approximately 1 in. protrudes from the holes on the top of the string head.  Remove old line by pulling it from the holes located on the top of the string head. CLEANING THE EXHAUST PORT AND MUFFLER NOTE: Depending on the type of fuel used, the type and amount of lubricant used, and/or your operating conditions, the exhaust port, muffler, and/or spark arrestor screen may become blocked with carbon deposits. If you notice a power loss with your gas powered tool, you may need to remove these deposits to restore performance. We highly recommend that only qualified service technicians perform this service. SPARK ARRESTOR The spark arrestor must be replaced every 50 hours or yearly to ensure proper performance of your product. Spark arrestors may be in different locations depending on the model purchased. Please contact your nearest service dealer for the location of the spark arrestor for your model. IDLE SPEED ADJUSTMENT See Figure 23. If the cutting attachment turns at idle, the idle speed screw needs adjusting on the engine. Turn the idle speed screw counterclockwise to reduce the idle RPM and stop the cutting attachment movement. If the cutting attachment still moves at idle speed, contact a service dealer for adjustment and discontinue use until the repair is made. WARNING: The cutting attachment should never turn at idle. Turn the idle speed screw counterclockwise to reduce the idle RPM and stop the cutting attachment, or contact a service dealer for adjustment and discontinue use until the repair is made. Serious personal injury may result from the cutting attachment turning at idle. CLEANING AIR FILTER SCREEN See Figures 24 - 25. For proper performance and long life, keep air filter screen clean.  Remove the air filter cover by pushing down on the latch with your thumb while gently pulling on the cover.  Brush the air filter screen lightly to clean.  Replace the air filter cover by inserting the tabs on the bottom of the cover into the slots on the air filter base; push the cover up until it latches securely in place. FUEL CAP WARNING: Check for fuel leaks. A leaking fuel cap is a fire hazard and must be replaced immediately. If you find any leaks, correct the problem before using the product. Failure to do so could result in a fire that could cause serious personal injury. The fuel cap contains a non-serviceable filter and a check valve. A clogged fuel filter will cause poor engine performance. If performance improves when the fuel cap is loosened, check valve may be faulty or filter clogged. Replace fuel cap if required. SPARK PLUG REPLACEMENT This engine uses an Champion RY4C spark plug with .025 in. electrode gap. Use an exact replacement and replace ­annually. CHANGING ENGINE LUBRICANT See Figure 26. For best performance, engine lubricant should be changed after every 25 hours of operation. To change the engine lubricant:  Stop the engine and disconnect the spark plug wire. Allow the engine to cool completely before proceeding.  Remove the screw from the top engine cover and set aside.  Remove the screws from the bottom of the engine cover. Remove the bottom cover and set aside.  Remove the oil fill cap/dipstick.  Tip powerhead on its side and allow lubricant to drain from the oil fill hole into an approved container. NOTE: Drain the lubricant while the engine is still warm but not hot. Warm lubricant will drain quickly and more completely.  Return the power head to an upright position and refill with lubricant following the instructions in the Adding/ Checking Engine Lubricant section previously in this manual.  Reinstall the bottom engine cover. Replace the screws and tighten securely.  Replace the screw in the top engine cover and tighten ­securely. NOTE: Used lubricant should be disposed of at an ­approved disposal site. See your local retailer for more information. 12 - English