Page 2 - NOTE; INTRODUCTION; CONTENTS OF CARTON
THANK YOU Thank you for buying this quality product. Thismodern outdoor power tool will provide manyhours of useful service. You will find it to be agreat labor-saving device. This operator’smanual provides you with easy-to-understandoperating instructions. Read the whole manualand follow all the in...
Page 3 - This unit is not factory equipped with a spark arrestor.; Optional Accessory Part #180030 Spark Arrestor Kit.; California Proposition 65 Warning:; THE ENGINE EXHAUST FROM THIS
3 WARNING! SPARK ARRESTOR WARNING CALIFORNIA EMISSION REGULATIONS NOTE: For users on U.S. Forest Land and in the states of California, Maine, Oregon and Washington. All U.S. Forest Land and the states of California (Public Resources Codes 4442 and 4443), Oregon andWashington require, by law that cer...
Page 4 - RULES FOR SAFE OPERATION; READ ALL INSTRUCTIONS; BEFORE OPERATING; • IMPORTANT SAFETY INFORMATION •; SYMBOL
RULES FOR SAFE OPERATION 4 • Clear the area to be cut before each use.Remove all objects such as rocks, brokenglass, nails, wire, or string which can bethrown or become entangled in the cuttingattachment. Clear the area of children,bystanders, and pets. At a minimum, keep allchildren, bystanders and...
Page 5 - WHILE OPERATING
RULES FOR SAFE OPERATION 5 • Always stop the engine and allow it to coolbefore filling the fuel tank. Never remove thecap of the fuel tank, or add fuel, when theengine is hot. Never operate the unit withoutthe fuel cap securely in place. Loosen thefuel tank cap slowly to relieve any pressure inthe t...
Page 6 - WHILE OPERATING WITH CUTTING; Blade thrust; AFTER USE; Cleaning and Storage; SAVE THESE INSTRUCTIONS
6 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. • NEVER cut...
Page 8 - FULL CHOKE
8 RULES FOR SAFE OPERATION • THROWN OBJECTS AND ROTATING CUTTER CAN CAUSE SEVERE INJURY WARNING: Do not operate without the cutting attachment shield in place. Keep away from the rotating cuttingattachment. • ON/OFF STOP CONTROL ON / START / RUN • ON/OFF STOP CONTROL OFF OR STOP • HOT SURFACE WARNIN...
Page 9 - KNOW YOUR UNIT
On/Off Stop Control RULES FOR SAFE OPERATION 9 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 to1/2 inch in diameter. Other accessories may be used with the790r...
Page 10 - ASSEMBLY INSTRUCTIONS; Top Clamp
ASSEMBLY INSTRUCTIONS 10 INSTALLING AND ADJUSTING THE J-HANDLE 1. Place the J-handle between the top and middle clamp pieces (Fig. 1). (4) Screws Top Clamp J-Handle Middle Clamp Bottom Clamp Nuts 2. While holding the three pieces together, install the four (4) screws through the topclamp and into mi...
Page 11 - NOT; INSTALLING THE HARNESS; Shield Mount
Install the cutting attachment shieldwhen using the unit as a grasstrimmer. WARNING : To avoid serious personal injury, the cuttingattachment shield SHALL be in place at all times while operating theunit as a grass trimmer. Install the cutting attachment shield on theshield mount by inserting the th...
Page 12 - Install the Cutting Blade
4. Center the cutting blade on the pilot step of the output shaft bushing (Fig. 11). Guard Mount Fig. 10 ASSEMBLY INSTRUCTIONS 12 Install the Cutting Blade WARNING: To avoid serious personal injury, always wear gloveswhile handling or installing the blade. 3. Place the cutting blade on the output sh...
Page 13 - Counterclockwise
5. Make sure that the cutting blade is centered on the pilot step and sitting flat against theoutput shaft bushing (Fig. 12). WARNING: If the cutting blade is off-center, the unit will vibrate, andthe blade may fly off, which cancause serious personal injury. ASSEMBLY INSTRUCTIONS 13 6. Align the sh...
Page 14 - Install the Cutting Attachment
ASSEMBLY INSTRUCTIONS 14 Cutting Attachment Locking Rod 4. Remove the nut, blade retainer, and blade. Store the nut and blade together for futureuse in a secure place. Store out of reach ofchildren. Install the Cutting Attachment 5. Align the shaft bushing hole with the locking rod slot and insert t...
Page 15 - OIL AND FUEL INFORMATION; UNLEADED GAS
15 WARNING: Gasoline is extremely flammable. Ignited Vapors mayexplode. Always stop the engine andallow it to cool before filling the fueltank. Do not smoke while filling thetank. Keep sparks and open flamesat a distance from the area. WARNING: Remove fuel cap slowly to avoid injury from fuel spray....
Page 16 - STARTING/STOPPING INSTRUCTIONS; STOPPING INSTRUCTIONS
STARTING/STOPPING INSTRUCTIONS 16 4. Place the choke lever in the FULL choke position (A) (Fig. 19). 8. If the engine does not start, repeat steps 4 through 7. NOTE: If the engine floods while trying tostart, place the choke lever in the RUN position (C) . Squeeze the throttle control. Pull the star...
Page 17 - OPERATING INSTRUCTIONS; OPERATING THE CLICK-LINK
CAUTION: The cutting attachment and add-ons with the Click-Link ® system are to be used in the primaryhole unless stated otherwise in thespecific add-ons operator’s manual.Using the wrong hole could lead topersonal injury, or damage to theunit. NOTE: For edging with Click-Link ® models, lock the rel...
Page 18 - HOLDING THE TRIMMER; ADJUSTING TRIMMING LINE LENGTH
HOLDING THE TRIMMER WARNING: Always wear eye, hearing, foot and body protection to reduce the risk of injury whenoperating this unit. Before operating the unit, stand in the operatingposition (Fig. 24). Check for the following: • The operator is wearing eye protection andproper clothing. • The right...
Page 19 - USING THE CUTTING BLADE; WARNING: Blade thrust
TIPS FOR BEST TRIMMING RESULTS • Keep the cutting attachment parallel to theground. • Do not force the cutting attachment. Allowthe tip of the line to do the cutting, especiallyalong walls. Cutting with more than the tipwill reduce cutting efficiency and mayoverload the engine. • Cut grass over 8 in...
Page 20 - MAINTENANCE SCHEDULE
• 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 notcutting. WARNING: The blade continues to spin after the engine is turned off.The coasting blade can seriously cutyou if accidentally touched...
Page 21 - MAINTENANCE AND REPAIR INSTRUCTIONS; LINE INSTALLATION; Indexing Teeth
MAINTENANCE AND REPAIR INSTRUCTIONS 21 LINE INSTALLATION Always use genuine Ryobi 0.095 in. (2.41 mm.)replacement line. Larger line may make theengine overheat or fail. WARNING: Do not use metal reinforced line. There are two methods to replace the trimmingline. • Wind the inner reel with new line •...
Page 22 - Holding Slots
9. Place the spring in the inner reel. Insert the ends of the line through the eyelets in theouter spool and place inner reel inside theouter spool (Fig. 35). Push the inner reel andouter spool together. While holding the innerreel and outer spool, grasp the ends and pullfirmly to release the line f...
Page 23 - Installing a Prewound Reel; PARTIAL
MAINTENANCE AND REPAIR INSTRUCTIONS 23 Installing a Prewound Reel 1. Hold the outer spool with one hand and unscrew the Bump Knob™ counterclockwise (Fig. 29, Pg 21). Inspect the bolt inside the Bump Knob™ to make sure it moves freely.Replace the Bump Knob™ if damaged. 2. Remove the old inner reel fr...
Page 24 - Reinstalling the Air Filter/Muffler Cover; Cleaning the Air Filter; VOID
MAINTENANCE AND REPAIR INSTRUCTIONS 24 6. Replace the air filter in the air filter/muffler cover (Fig. 37). NOTE: Operating the unit without the air filter and air filter/muffler cover assembly, will VOID the warranty. Reinstalling the Air Filter/Muffler Cover 1. Place the air filter/muffler cover o...
Page 25 - CARBURETOR ADJUSTMENT; Oil and Fuel Information; Clean Air Filter; Air Filter Maintenance; Adjust Idle Speed Screw; Idle Speed Screw
MAINTENANCE AND REPAIR INSTRUCTIONS 25 CARBURETOR ADJUSTMENT The idle speed of the engine is adjustablethough the Air filter/muffler cover (Fig 41). NOTE: Careless adjustments can seriouslydamage your unit. An authorizedservice dealer should make carburetoradjustments. Check Fuel Mixture Old and/or ...
Page 26 - REPLACING THE SPARK PLUG
MAINTENANCE AND REPAIR INSTRUCTIONS 26 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...
Page 27 - CLEANING AND STORAGE; TRANSPORTING
CLEANING AND STORAGE 27 TRANSPORTING • Allow the engine to cool before transporting. • Secure the unit while transporting. • Drain the fuel tank before transporting. • Tighten fuel cap before transporting. CLEANING WARNING: To avoid serious personal injury, always turn yourtrimmer off and allow it t...
Page 28 - TROUBLESHOOTING; PROBLEM
TROUBLESHOOTING 28 Engine will not start Engine will not idle Low idle speed Engine will not accelerate Engine lacks power orstalls when cutting Cutting head will notadvance line Ignition switch is OFF Empty fuel tank Primer bulb wasn't pressedenough Engine flooded Old or Improperly Mixed Fuel Foule...
Page 29 - SPECIFICATIONS; ENGINE
SPECIFICATIONS 29 ENGINE Engine Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air-Cooled, 2-CycleStroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.25 in. (31.75 m...
Page 30 - NOTES
Page 32 - RYOBI OUTDOOR PRODUCTS; LIMITED TWO-YEAR WARRANTY; SAVE THESE INSTRUCTIONS FOR FUTURE REFERENCE.
RYOBI OUTDOOR PRODUCTS warrants each newRYOBI Product for two (2) years according to thefollowing terms. This warranty extends to the original retail purchaseronly and commences on the date of original retailpurchase. Any part of the RYOBI Product manufactured orsupplied by RYOBI and found in the re...
