780r–790r 2-Cycle Gas Trimmer/Brushcutter OPERATOR’S MANUAL FOR QUESTIONS, CALL 1-800-345-8746 in U.S. or 1-800-265-6778 in CANADA www.ryobi.com IMPORTANT MANUAL DO NOT THROW AWAY...
VI. Operating Instructions ... 17-20 A. Operating Click-Link System (790r) . . .17 B. Holding the Trimmer ....18 C. Adjusting Trimming Line Length ..18 D.
CALIFORNIA EMISSION REGULATIONS This unit meets the 1995 to 1998 California emissions regulations for small off-road engines. These units are identified by the label on the engine of your product. A typical identification label is shown. To ensure that your unit continues to meet these regulations, refer to the following information and instructions in this operator’s manual.
• Use only 0.095 in (2.41 mm) diameter genuine Ryobi replacement line. Never use metal-reinforced line, wire, or rope, etc.. These can break off and become a dangerous projectile.
• Stop and switch the engine to off for maintenance, repair, or for changing the cutting attachment or other attachments. • Use only genuine Ryobi replacement parts when servicing this unit. These parts are available from your authorized service dealer. Do not use parts, accessories or attachments not authorized by Ryobi for this unit.
RULES FOR SAFE OPERATION WHILE OPERATING WITH CUTTING BLADE • Read and understand all safety warnings before operating this unit. • Always use the shoulder harness when using the brush blade accessory. • Keep the handle between the operator and cutting attachment or blade at all times. •...
RULES FOR SAFE OPERATION 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. SYMBOL • SAFETY ALERT SYMBOL •...
WARNING: Thrown objects and rotating cutter can cause severe injury. Keep bystanders, especially children and pets, at least 50 feet (15 m.) away from the cutting area. The cutting attachment shield must be used when using the trimmer cutting attachment.
RULES FOR SAFE OPERATION KNOW YOUR UNIT APPLICATIONS As a trimmer; • Cutting grass and light weeds. • Edging • Decorative trimming around trees, fences, etc. As a brushcutter; • Cutting weeds and light bush of up to 1/2 inch in diameter.
ASSEMBLY INSTRUCTIONS INSTALLING AND ADJUSTING THE J-HANDLE 1. Place the J-handle between the top and middle clamp pieces (Fig. 1). (4) Screws Top Clamp Middle Clamp Bottom Clamp Nuts Fig. 1 2. While holding the three pieces together, install the four (4) screws through the top clamp and into middle clamp.
Remove the cutting attachment shield before removing or installing the blade. (3) Screws Shield Mount Fig. 7 WARNING: To avoid serious personal injury, the cutting attachment shield SHALL be in place at all times while operating the unit as a grass trimmer.
ASSEMBLY INSTRUCTIONS REMOVING THE CUTTING ATTACHMENT AND INSTALLING THE CUTTING BLADE NOTE: To make removing or installing the cutting blade or cutting attachment easier, place the unit on the ground or on a work bench. Remove the Cutting Attachment Shield See Removing and Installing Cutting Attachment Shield, Pg.
ASSEMBLY INSTRUCTIONS 5. Make sure that the cutting blade is centered on the pilot step and sitting flat against the output shaft bushing (Fig. 12). WARNING: If the cutting blade is off-center, the unit will vibrate, and the blade may fly off, which can cause serious personal injury.
Locking Rod Fig. 17 WARNING: To avoid serious personal injury, the cutting attachment shield SHALL be in place at all times while operating the unit as a grass trimmer.
Thoroughly mix the proper ratio of 2-cycle engine oil with unleaded gasoline in a separate gasoline mixed with one 4 oz. (120 ml.) bottle of RYOBI 2 Cycle OIL makes a 32:1 fuel/oil ratio. RYOBI 2 CYCLE OIL 1 US. GALLON 4.0 FL.
STARTING/STOPPING INSTRUCTIONS STARTING INSTRUCTIONS WARNING: Avoid accidental starting. Be in the starting position when pulling the starter rope (Fig. 20). The operator and unit must be in a stable position while starting to avoid serious personal injury. 1. Mix gas with oil. Fill fuel tank with fuel/oil mixture.
Snowthrower ....ST720r Straight Shaft Trimmer ... . . SS725r Sweeper/Blower ....SB720r Tree Pruner .
To release more line, lightly tap the cutting attachment on the ground (Fig. 25) while operating the trimmer at high speed. NOTE: Always keep the trimming line fully extended. Line release becomes more difficult as cutting line becomes shorter.
Cutting to the right improves the unit's cutting efficiency. Clippings are thrown away from the operator. • Slowly move the trimmer into and out of the cutting area at the desired height. Move either in a forward-backward or side-to-side motion. Cutting shorter lengths produces the best results.
OPERATING INSTRUCTIONS • Cut while swinging the upper part of your body from right to left. • Always release the throttle trigger and allow the engine to return to idle speed when not cutting. WARNING: The blade continues to spin after the engine is turned off. The coasting blade can seriously cut you if accidentally touched.
MAINTENANCE AND REPAIR INSTRUCTIONS LINE INSTALLATION Always use genuine Ryobi 0.095 in. (2.41 mm.) replacement line. Larger line may make the engine overheat or fail. WARNING: Do not use metal reinforced line. There are two methods to replace the trimming line.
MAINTENANCE AND REPAIR INSTRUCTIONS 6. Take approximately 25 feet (7.6 m) 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. 32). Pull the line through the inner reel so that the loop is as small as possible.
AIR FILTER MAINTENANCE Removing the Air Filter/Muffler Cover WARNING: To avoid serious personal injury, always turn your trimmer off and allow it to cool before you clean or do any maintenance on it. 1. Place the choke lever in the PARTIAL choke position (B).
MAINTENANCE AND REPAIR INSTRUCTIONS Cleaning the Air Filter WARNING: To avoid serious personal injury, always turn your trimmer off and allow it to cool before you clean or do any maintenance on it. Clean and re-oil the air filter every 10 hours of operation.
MAINTENANCE AND REPAIR INSTRUCTIONS CARBURETOR ADJUSTMENT The idle speed of the engine is adjustable though the Air filter/muffler cover (Fig 41). NOTE: Careless adjustments can seriously damage your unit. An authorized service dealer should make carburetor adjustments. Check Fuel Mixture Old and/or improperly mixed fuel is usually the reason for the unit not running properly.
MAINTENANCE AND REPAIR INSTRUCTIONS REPLACING THE SPARK PLUG Use a Champion RDJ7Y spark plug (or equivalent). The correct air gap is 0.020 in. (0.5 mm.). Remove the plug after every 50 hours of operation and check its condition. 1. Stop the engine and allow it to cool. Grasp the plug wire firmly and pull the cap from the spark plug.
CLEANING AND STORAGE CLEANING WARNING: To avoid serious personal injury, always turn your trimmer off and allow it to cool before you clean or do any maintenance on it. Use a small brush to clean off the outside of the unit.
PROBLEM Engine will not start Engine will not idle Low idle speed Engine will not accelerate Engine lacks power or stalls when cutting Cutting head will not advance line TROUBLESHOOTING CAUSE Ignition switch is OFF Empty fuel tank Primer bulb wasn't pressed enough Engine flooded Old or Improperly Mixed Fuel...
Operating RPM (Trimmer) ........
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 small off-road engine. In California, new small off-road engines must be designed, built and equipped to meet the State's stringent anti-smog standards.
RYOBI Operator’s Manual. This warranty does not apply to any damage to the RYOBI Product that is the result of improper maintenance or to any RYOBI Product that has been altered or modified so as to...