Cleaning And Storage; Optional Accessory; Troubleshooting Chart; Specifications - Troy-Bilt TB21 EC Manual Del Operador

MAINTENANCE AND REPAIR INSTRUCTIONS
MAINTAINING THE SPARK PLUG
1. Stop the engine and allow it to cool. Grasp the spark plug boot firmly and pull it from the spark plug.
2. Clean around the spark plug. Remove the spark plug from the cylinder head with a 5/8-inch socket, turning
counterclockwise.
WARNING:
Do not sand blast, scrape or clean spark plug
electrodes. Grit in the engine could damage the cylinder.
3. Inspect the spark plug. If the spark plug is cracked, fouled or dirty, replace it with
a replacement part #753-06193, a Champion RDJ7J or an equivalent spark plug.
4. Use a feeler gauge to set the air gap at 0.025 in. (0.635 mm) (Fig. 28).
5. Install the spark plug in the cylinder head. Tighten the spark plug with a 5/8-inch
socket, turning it clockwise until snug.
NOTE: If using a torque wrench, torque to:
110-120 in.•lb. (12.3-13.5 N•m). Do not over tighten.
6. Reattach the spark plug boot.

CLEANING AND STORAGE

CLEANING
WARNING:
To avoid serious personal injury, always stop the engine and allow it to cool before
cleaning or maintaining the unit.
Use a small brush to clean the outside of the unit. Do not use strong detergents. Household cleaners that contain
aromatic oils such as pine and lemon, and solvents such as kerosene, can damage plastic. Wipe off any moisture with
a soft cloth.
STORAGE
• Never store a fueled unit where fumes may reach an open flame or spark.
• Allow the engine to cool before storing.
• Lock up the unit to prevent unauthorized use or damage.
• Store the unit in a dry, well-ventilated area.
• Store the unit out of the reach of children.
Short-term Storage (1-2 weeks)
1. Store the unit in a horizontal position. If this is not possible, store the unit vertically with the engine at the top.
Long-term Storage
1. Remove the fuel cap, tip the unit and drain the fuel into an approved container.
2. Start the engine and allow it to run until it stalls. This ensures that all fuel has been drained from the carburetor.
3. Allow the engine to cool. Remove the spark plug and put 5 drops of any high quality motor oil or 2-cycle oil into the
cylinder. Pull the starter rope slowly to distribute the oil. Reinstall the spark plug.
4. Thoroughly clean the unit and inspect it for any loose or damaged parts. Repair or replace damaged parts and
tighten loose screws, nuts or bolts.
Preparing the Unit for Use after Long-term Storage
1. Remove the spark plug and drain all of the oil from the cylinder.
NOTE: Do not use fuel that has been stored for more than 30 days. Dispose of old fuel according to federal, state
and local regulations.

OPTIONAL ACCESSORY

ELECTRIC STARTER AND POWER START BIT™ FEATURES
This unit is designed to be started with an optional electric starter or Power Start Bit™ that are sold separately. If choosing
to start the unit using one of these features or have questions please contact your local retailer or call 1-800-828-5500 U.S,
(1-800-668-1238 Canada), for more information and purchasing. You may also go to www.troybilt.com or
www.troybilt.ca.
ENGINE WILL NOT START
Empty fuel tank
Primer bulb wasn't pressed enough
Engine is flooded
Old or improperly mixed fuel
Fouled spark plug
0.025 in.
(0.635 mm)
ENGINE WILL NOT IDLE
Fig. 28
Air filter is plugged
Old or improperly mixed fuel
The idle speed is incorrect
ENGINE WILL NOT ACCELERATE
Old or improperly mixed fuel
Cutting head bound with grass
Dirty air filter
ENGINE LACKS POWER OR STALLS
Old or improperly mixed fuel
Fouled spark plug
ENGINE STOPS WHILE IN USE
Engine overspeed protection engaged
CUTTING HEAD WILL NOT ADVANCE LINE
Cutting head bound with grass
Cutting head out of line
Inner reel bound up
Cutting head dirty
Line welded
Line twisted when refilled
Not enough line is exposed
CUTTING LINE ADVANCES UNCONTROLLABLY
Oil, cleaner or lubricant in cutting head
IF FURTHER ASSISTANCE IS REQUIRED, CONTACT AN AUTHORIZED SERVICE DEALER.
Engine Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air-Cooled, 2-Cycle
Displacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 cc
Operating RPM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6,800+ rpm
Idle Speed RPM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,800 - 3,400 rpm
Spark Plug Gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.025 in. (0.635 mm)
Lubrication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel/Oil Mixture
Fuel/Oil Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40:1
Fuel Tank Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 fl.oz. (414 ml)
Total Approximate Unit Weight (without fuel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 lbs. (4.5 kg)
Cutting Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bump Head™
Shoulder Strap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Optional
Trimming Line Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.095 in. (2.41 mm)
Cutting Path Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 in. (40.64 cm)
*All specifications are based on the latest product information available at the time of printing. We reserve the right to
Electric Start Feature
make changes at any time without notice.
Fig. 29
TROUBLESHOOTING
CAUSE

SPECIFICATIONS*

ACTION
Fill fuel tank with properly mixed fuel
Press primer bulb fully and slowly 10 times
With the choke lever in position 3, squeeze the trigger
and pull the starter rope
Drain fuel tank and add fresh fuel mixture
Replace or clean the spark plug
Replace or clean the air filter
Drain fuel tank and add fresh fuel mixture
Adjust the idle speed
Drain fuel tank and add fresh fuel mixture
Stop the engine and clean the cutting head
Clean or replace the air filter
Drain fuel tank and add fresh fuel mixture
Replace or clean the spark plug
Allow the engine to cool down for 10 minutes before
restarting.
Stop the engine and clean cutting head
Refill with new line
Rewind the inner reel
Clean inner reel and outer spool
Disassemble, remove the welded section and rewind
Disassemble and rewind the line
Push the bump knob and pull out line until 4 inches (102 mm)
of line is outside of the cutting head
Clean and thoroughly dry the cutting head
5