Ryobi RY905500 User Manual 6 - Page 20

MAINTENANCE WARNING: Do not change engine lubricant while it is hot. Accidental contact with hot engine lubricant could result in serious burns.  Reinstall the oil drain plug and tighten securely.  Refill with lubricant following the instructions in the ­Checking/Adding Lubricant section. For amount of lubricant needed to refill, see Product Specifications earlier in this manual or the accompanying engine manual, if applicable.  Reinstall the oil cap/dipstick. NOTE: Used lubricant should be disposed of at an approved disposal site. See your local oil retailer for more information. SPARK PLUG MAINTENANCE See Figure 16. The spark plug must be properly gapped and free of deposits in order to ensure proper engine operation. To check:  Remove the spark plug cap.  Clean any dirt from around base of spark plug.  Remove spark plug using wrench (not included).  Inspect spark plug for damage, and clean with a wire brush before reinstalling. If insulator is cracked or chipped, spark plug should be replaced. For replacement spark plug, see Product Specifications earlier in this manual or the accompanying engine manual, if applicable.  Measure plug gap. The correct gap is 0.028−0.031 in. (0.7-0.8 mm). To widen gap, if necessary, carefully bend the ground (top) electrode. To lessen gap, gently tap ground electrode on a hard surface.  Seat spark plug in position; thread in by hand to prevent cross-threading.  Tighten with wrench to compress washer. If spark plug is new, use 1/2 turn to compress washer appropriate amount. If reusing old spark plug, use 1/8 to 1/4 turn for proper washer compression. NOTE: An improperly tightened spark plug will become very hot and could damage the engine. CLEANING THE EXHAUST PORT AND MUFFLER Depending on the type of fuel used, the type and amount of lubricant used, and/or your operating conditions, the exhaust port and muffler may become blocked with carbon deposits. If you notice a power loss with your gas-powered products, you may need to remove these deposits to restore performance. We highly recommend that only qualified service technicians perform this service. SPARK ARRESTOR See Figure 17. NOTICE: This product is equipped with a spark arrestor that has been evaluated by the USDA Forest Service; however, product users must comply with Federal, State, and local fire prevention regulations. Check with appropriate authorities. Contact customer service or a qualified service center to purchase a replacement spark arrestor.  Inspect the spark arrestor screen for breaks or holes. Replace if necessary.  Use a brush (not provided) to remove carbon deposits from the spark arrestor screen as needed. DRAINING FUEL TANK/CARBURETOR See Figures 18 - 19. To help prevent gum deposits in the fuel system, drain the fuel from the tank and carburetor before storing. DRAINING THE FUEL TANK  Place the choke lever in the OFF position.  Remove the fuel line from the fuel valve by squeezing the ends of the retaining clip and sliding the fuel line off.  Install one end of a drain line over the fuel valve, and place the other end in a fuel container large enough to catch the fuel being drained from the tank.  Place the choke lever in the RUN position.  When the fuel has drained from the tank, place the choke lever in OFF position and reinstall fuel line securely onto the fuel valve. DRAINING THE CARBURETOR  Place the choke lever in the OFF position.  Position a suitable container under the carburetor drain screw to catch fuel; loosen the screw.  Allow fuel to drain completely into container.  Retighten drain screw. NOTE: Consult hazardous waste management guidelines in your area for the proper way to dispose of used fuel. Page 16 - English