990r OPERATOR’S MANUAL MODEL NO.
INTRODUCTION TABLE OF CONTENTS THANK YOU I. California Emission Regulations ................................3 Thank you for purchasing this quality product. This modern outdoor power tool has been designed to provide you with many hours of useful service. You will find it to be a great labor-saving device. II. Safety Warnings ......................................................3-6 A. Safety Warnings for Brush Blade ..........................4 B. Safety and International Symbols ....................
CALIFORNIA EMISSION REGULATIONS The engine of your lawn and garden care product meets the 1995 California emissions regulations. To ensure that your unit continues to meet these regulations, refer to the following information and instructions in this operator's manual. These units are identified by the label on the engine of your product. A typical identification label is shown. SAFETY WARNINGS THE PURPOSE OF SAFETY SYMBOLS IS TO ATTRACT YOUR ATTENTION TO POSSIBLE DANGERS.
SAFETY WARNINGS OPERATIONAL • Wear safety glasses/goggles at all times when operating this trimmer. • Dress properly. Do not operate this trimmer when barefoot or wearing open sandals. Always wear sturdy, rubber-soled footwear. The use of gloves, ear/hearing protection and long pants are recommended. • • Do not wear loose fitting clothing or articles such as scarves, strings, chains, ties, etc. because they could get drawn into the air intake.
SAFETY WARNINGS (Continued) SAFETY AND INTERNATIONAL SYMBOLS This operator's manual describes safety and international symbols and pictographs that may appear on this product. Read the operator's manual for complete safety, assembly, operating and maintenance and repair information. SIGNIFICATION SYMBOL • SAFETY ALERT SYMBOL. Indicates caution, warning or danger. May be used in conjunction with other symbols or pictographs. • READ OPERATOR'S MANUAL.
SAFETY WARNINGS (Continued) SYMBOL SIGNIFICATION • PRIMER BULB. Push primer bulb, fully and slowly, 5 to 7 times. • CHOKE CONTROL. FULL CHOKE position. • CHOKE CONTROL. PARTIAL CHOKE position. • CHOKE CONTROL. RUN position. • THROWN OBJECTS AND ROTATING CUTTER CAN CAUSE SEVERE INJURY. Warning. Do not operate without guard in place. Keep away from rotating cutter. • BRUSHCUTTERS – REPLACE DULL BLADE. Do not sharpen the brush blade.
ASSEMBLY INSTRUCTIONS ADJUSTING THE J-HANDLE The J-handle is shipped completely assembled on Model 990r (Fig. 1). Use the following instructions to adjust the J-handle to the correct operating position. 1. Loosen the four (4) mounting screws on the J-handle. It is not necessary to remove the screws. 2. Slide the J-handle through the clamp until the arrow / white line on the decal touches the clamp assembly (Fig. 2). 3.
ASSEMBLY INSTRUCTIONS (Continued) INSTALLING THE BRUSH BLADE 1. Remove the line guard. 2. Insert the locking rod into the locking rod slot. Rotate the line spool clockwise. Remove the line spool and retainer washer from the shaft (Fig. 6). Line Guard Locking Rod Slot 4. Install the blade, washer, and lock nut. Insert the locking rod into the locking rod slot (Fig. 7). Make sure that the blade stays flat against the washer while tightening the lock nut counterclockwise until it is finger-tight. 5.
ASSEMBLY INSTRUCTIONS (Continued) 6. When assembling the brush blade, the blade edge should line up with the blade locating mark on the casting (Fig. 10). The brush blade should be within a blade thickness of the mark. If the blade isn't lined up correctly, refer to Fig. 7 for reassembly. Blade Locating Mark Fig. 10 WARNING Make sure the blade is flat against the washer after the lock nut is tightened. If the blade is off-center, the trimmer will be damaged by vibration, and the blade may fly off.
ASSEMBLY INSTRUCTIONS (Continued) OPERATING THE SPLIT BOOM® COUPLER Installing the Lower (Attachment) Boom 1. Loosen the wing screws. This will allow the lower boom to be inserted into the coupler (Fig. 12). Model 990r is equipped with a Split Boom® coupler, which enables optional attachments to be installed on this unit. 2. Remove the protective cover or hanger from the lower (attachment) boom. Push the lower (attachment) boom into the coupler (Fig. 13). The optional attachments are: 3.
OIL & FUEL INFORMATION THIS ENGINE IS CERTIFIED TO OPERATE ON UNLEADED GAS ONLY. NOTE: BE SURE TO READ THESE INSTRUCTIONS CAREFULLY BEFORE ATTEMPTING TO START OR OPERATE THIS UNIT. Using old or improper oil or fuel can cause engine damage. This type of damage will void the engine warranty. RECOMMENDED OIL TYPE Using the proper type and weight of oil in the crankcase is extremely important. Check the oil before each use and change the oil regularly.
OIL & FUEL INFORMATION (Continued) RECOMMENDED FUEL TYPE WARNING O-ring Full (100 ml/3.4 oz) Add Oil Fig. 17 Fuel is extremely flammable and its vapors can explode if they are ignited. Always stop the engine and allow it to cool before filling the fuel tank. Do not smoke while filling the tank. Keep sparks and open flames away from the area. Fill the fuel tank, using clean, fresh, unleaded gasoline. NOTE: CHANGING THE OIL For a new engine, change the oil after the first 10 hours of operation.
STARTING/STOPPING INSTRUCTIONS 1. CHECK THE OIL LEVEL IN THE CRANKCASE, AND PUT THE IGNITION SWITCH IN THE "RUN" (I) POSITION. See Figure 20 for the location of the ignition switch. Ignition Switch STOP (O) RUN (I) 2. FULLY PRESS AND RELEASE THE PRIMER BULB 5 TO 7 TIMES. See Fig. 21 for the primer bulb location. 3. PLACE THE CHOKE LEVER IN THE FULL “CHOKE” POSITION. See Fig. 21.
OPERATING INSTRUCTIONS ADJUSTING THE TRIMMING LINE LENGTH Your trimmer is equipped with a bump head that allows the operator to release more trimming line without stopping the engine. To release additional line, lightly tap the trimming head on the ground (Fig. 23) while operating the trimmer at high speed. USING THE BRUSH BLADE 1. Always maintain the proper stance when using the brush blade (Fig. 25). Sharpening the Brush Blade WARNING Do not sharpen the brush blade.
MAINTENANCE AND REPAIR INSTRUCTIONS MAINTENANCE SCHEDULE These required maintenance procedures should be performed at the frequency stated in the table. They should also be included as part of any seasonal tune-up. FREQUENCY MAINTENANCE REQUIRED Daily or Before Starting Engine Fill fuel tank. Check oil level. Every 10 Hours Change oil after initial use. Clean and re-oil air filter. Every 25 Hours Change oil. Every 50 Hours Check spark plug condition and gap. Check rocker arm to valve clearance.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) 2. Remove the inner reel (Fig. 27). LINE INSTALLATION The trimming line may be replaced by two different methods - rewinding the existing reel or installing a prewound reel. REWINDING THE EXISTING REEL To rewind the existing reel you must: Inner Reel 1. 2. 3. 4. Check for the correct line size. Remove the existing reel and spring. Wind the existing reel with the new line. Reinstall the existing reel and spring. Fig. 27 The Correct Line to Use 3.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) Winding the Existing Reel 1. Take approximately 12.7 m (50 ft) of new trimming line, loop it into two equal lengths. Insert each end of the line through one of the two holes in the inner reel (Fig. 30). Pull the line so that the loop is as small as possible. Fig. 32 Reinstalling the Reel Fig. 30 2. Wind the lines, in even and tight layers, onto the reel (Fig. 31). Wind the line in the direction indicated on the inner reel.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) GEAR HOUSING SERVICE WARNING The gear housing gets very warm after long periods of use. Do not touch the housing until it has cooled. 1. Check the gear housing for lubricant every 50 hours of operation. 2. To check the lubricant level, remove the fill plug (Fig. 34). The lubricant should be up to the bottom edge of the check hole. If it is low, bring the level up with a good quality, lithium-based, #2, multi-purpose grease. 3.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) AIR FILTER MAINTENANCE NOTE: CLEAN AND RE-OIL THE AIR FILTER EVERY 10 HOURS OF OPERATION. Your unit’s air filter is one of the most important areas to maintain. If it is not maintained, you will void the warranty. Before cleaning, make sure the unit is turned off. 1. Remove the three (3) screws on the carburetor/air filter cover assembly. Remove the air filter cover (Fig. 35).
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) CARBURETOR ADJUSTMENT Throttle Lever This unit is equipped with a diaphragm-type carburetor that has been carefully calibrated at the factory. In most cases, no further adjustment will be required. NOTE: Idle Speed Screw To meet the 1995 California emission regulations, the carburetor has adjustment needle limiter caps to restrict the amount of adjustment. The condition of the air filter is important to the operation of the trimmer.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) CARBURETOR ADJUSTMENT (Continued) 8. Final Idle Speed Adjustment: Adjust the idle speed by turning the idle speed screw in (clockwise) or out (counterclockwise) until the cutting head does not rotate. Do not squeeze the throttle trigger when adjusting the idle speed screw. Definition of Optimum Setting for Idle Speed Mixture and High Speed Mixture Adjustments Always set the idle speed mixture needle and high speed mixture needle at the optimum setting.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) Muffler Reassembly Inspection and Cleaning Inspect the inlet port of the muffler and outlet port of the cylinder for excessive carbon build-up. Excessive deposits around the exhaust ports or exhaust holes will cause poor engine performance. If carbon build-up cannot be cleaned, replace the muffler. Inspect the muffler mounting holes for elongation. Replace the muffler if the holes are elongated. 1.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) REPLACING THE SPARK PLUG Use a Champion RDZ19H spark plug. Correct air gap is .025 in (0.635 mm). Remove plug after every 50 hours of operation and check its condition. Allow the engine to cool before removing the spark plug. CHECKING / ADJUSTING VALVE TO ROCKER ARM CLEARANCE Every 50 hours of operation, remove the rocker arm cover and check the valve to rocker arm clearance, using a flat feeler gauge. 1.
MAINTENANCE AND REPAIR INSTRUCTIONS (Continued) 3. Remove the rocker arm cover and gasket, using a T25 Torx® screwdriver (Fig. 50). The recommended valve to rocker arm clearance for both the intake and exhaust is 003-.006 in. (.076 mm-.152 mm). 6. If the clearance is not within specification, adjust as follows: a. Turn the adjusting nut (Fig. 52), using an 5/16 in (8 mm) wrench or nut driver. To increase the rocker arm to valve clearance, turn the adjusting nut counterclockwise.
CLEANING AND STORAGE 3. Drain the oil from the crankcase and add fresh oil. Pull the starter rope a few times to lubricate the engine. WARNING Always turn off your trimmer before you clean or perform any maintenance on it. 4. Thoroughly clean the unit and inspect for any loose or damaged parts. Repair or replace damaged parts and tighten loose screws, nuts or bolts. Cleaning The unit is now ready for storage. Use a small brush to clean off the outside of the trimmer.
TROUBLESHOOTING PROBLEM Engine Is Difficult to Start or Will Not Start CAUSE ACTION Ignition switch is “STOP (O)" Turn switch to “RUN (I)” Primer bulb wasn’t pushed enough Press primer bulb fully and slowly 5-7 times Engine is not choked Use starting procedure, USING "FULL" CHOKE" (Page 9) Empty fuel tank Fill fuel tank Engine flooded Use starting procedure, USING "PARTIAL" CHOKE (Page 9) Valve clearance is out of adjustment Use adjust valve to rocker arm clearance procedure (Pages 18 and 19)
CALIFORNIA EMISSION CONTROL WARRANTY STATEMENT YOUR WARRANTY RIGHTS AND OBLIGATIONS The California Air Resources Board and Ryobi Outdoor Products (ROP), are pleased to explain the emission control system warranty on your 1995 and later lawn and garden equipment engine. In California, new lawn and garden equipment engines must be designed, built and equipped to meet the State's stringent anti-smog standards.
Limited Two-Year Warranty RYOBI AMERICA CORP. warrants each new RYOBI Product for two (2) years according to the following terms. This warranty extends to the original retail purchaser only and commences on the date of original retail purchase. Any part of the RYOBI Product manufactured or supplied by RYOBI and found in the reasonable judgement of RYOBI to be defective in material or workmanship will be repaired or replaced by an authorized RYOBI service dealer without charge for parts and labor.
