21in Walk-Behind Aerator

• Read the Operator’s Manual and other training material. If the operator(s) or mechanic(s) cannot read English it is the owner’s responsibility to explain this material to them.

• Become familiar with the safe operation of the equipment, operator controls, and safety signs.

• All operators and mechanics should be trained. The owner is responsible for training the users.

• Never let children or untrained people operate or service the equipment. Local regulations may restrict the age of the operator.

• The owner/user can prevent and is responsible for accidents or injuries occurring to himself or herself, other people or property.

• Evaluate the terrain to determine what accessories and attachments are needed to properly and safely perform the job. Only use accessories and attachments approved by the manufacturer.

• Wear appropriate clothing including safety glasses and hearing protection. Long hair, loose clothing, or jewelry may get tangled in moving parts.

• Inspect the area where the equipment is to be used and remove all objects such as rocks, toys, and wire which can be contacted by the aerator.

• Use extra care when handling gasoline and other fuels. They are flammable and vapors are explosive.

  • Use only an approved container.

  • Never remove the gas cap or add fuel with the engine running.

  • Allow the engine to cool before refueling.

  • Do not smoke.

  • Never refuel or drain the aerator indoors.

• Check that the controls, safety switches, and shields are attached and functioning properly. Do not operate unless they are functioning properly.

• Never run an engine in an enclosed area.

• Only operate in good light, keeping away from holes and hidden hazards.

• Be sure all drives are in neutral before starting engine.

• Never operate without the shields, covers, or other guards securely in place. Be sure all interlocks are functioning properly.

• Do not change the engine governor setting or overspeed the engine.

• Raise the tines, stop the machine, and stop the engine before leaving the operator’s position for any reason.

• Stop the equipment and inspect the tines after striking an object or if an abnormal vibration occurs. Make necessary repairs before resuming operation.

• Keep hands and feet away from the tine area.

• Be alert, slow down, and use caution when making turns. Look behind and to the side before changing directions.

• Slow down and use caution when crossing roads and sidewalks.

• Do not operate the aerator under the influence of alcohol or drugs.

• Lightning can cause severe injury or death. If lightning is seen or thunder is heard in the area, do not operate the machine; seek shelter.

• Use extreme care when loading or unloading the aerator into a trailer or truck.

• Use care when approaching blind corners, shrubs, trees, or other objects that may obscure vision.

• Always be aware of obstacles that may be in the area of operation. Plan your aeration path to avoid contact with any obstacle by you or the machine.

• Do not make sudden turns or rapid speed changes.

• Reduce speed and use extreme caution on slopes.

• Remove or mark obstacles such as rocks, tree limbs, etc. from the operating area. Tall grass can hide obstacles.

• Wait for all movement to stop before adjusting, cleaning, or repairing. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

• Clean grass and debris from the tines, drives, mufflers, and engine to help prevent fires. Clean up oil or fuel spillage.

• Let the engine cool before storing and do not store near flame.

• Shut off the fuel while storing or transporting on trailers. Do not store fuel near flames or drain indoors.

• Park the aerator on level, hard ground. Never allow untrained personnel to service it.

• Use jack stands or safety latches to support the machine when working under it.

• Remove the spark plug wire before making any repairs.

• Keep hands and feet away from moving parts. If possible, do not make adjustments with the engine running.

• Keep all parts in good working condition and all hardware tightened. Replace all worn or damaged decals.

• Use only Toro-approved attachments. The warranty may be voided if the machine is used with unapproved attachments.

The machine has a rear access panel that you can remove to access and maintain the tines (Figure 21).

Figure 21

1. Rear access panel

If you need to work on the underside of the machine, you can tip it backward (Figure 22). Do not tip the machine forward or you will foul the air cleaner with gasoline. Secure the machine with a jack stand before working under it.

Figure 22

1. Jack stand

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Remove the rear access panel; refer to Accessing the Tines

3. Lubricate fittings with NGLI grade #2 multi-purpose gun grease.

   Refer to the following chart for fitting locations and lubrication schedule.

   Lubrication Chart

   Fitting Locations	Initial Pumps	Number of Places	Service Interval
   1. Tine Shaft Bearings	1	2	25 hours
   2. Tine Assembly Idlers	1-2	2	25 hours

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Raise the front of the machine to gain access to the chains (Figure 22) and block it in place.

   Caution

   If you do not securely block the up the front of the machine, the machine could fall on you during service, injuring you.

   Ensure that you place a jack-stand or block under the front of the machine to hold it up securely.

   Important: Do not raise the rear of the machine. Raising the rear of the machine will cause the engine to flood and the air cleaner to be fouled with gasoline.

3. Rotate the front wheels and apply oil or chain lubricant onto the links of the lower spans of the front drive chains (Figure 23).

   

   Figure 23

   1. Tine drive chains
   2. Front drive chains

4. Check the front drive chains (Figure 23) for wear, damage, and proper tension. If chains pop or snap, replace the sprockets and chains.

5. Rotate tine shafts and apply oil or chain lubricant onto all the links of the lower spans of the tine drive chains (Figure 23).

6. Check the chains on both sides of the unit for wear, damage, and proper tension. The chains should be able to move up and down 1/4 inch (6 mm) maximum.

   If chains are not tight enough or they pop or snap adjust the chain tension; refer to Adjusting the Tension of Tine Drive Chains.

7. Inspect all chain sprockets for wear and replace them as required.

8. Wipe up any oil that spilled and lower the machine to the ground when finished.

Important: Do not operate the engine without the air filter assembly; extreme engine damage may occur.

1. Stop the engine and wait for all moving parts to stop.

2. Disconnect the wire from the spark plug.

3. Remove the cover and clean it thoroughly ().

   Note: Be careful to prevent dirt and debris from falling into the base.

   

   Figure 24

   1. Cover
   2. Foam pre-cleaner
   3. Paper air filter

4. Remove the foam pre-cleaner and wash it with a mild detergent and water, then blot it dry (Figure 24).

5. Remove and inspect the paper air filter (); discard it if it is excessively dirty.

   Important: Do not try to clean a paper filter.

6. Wipe dirt from the base and the cover with a moist rag.

   Note: Be careful to prevent dirt and debris from entering the air duct leading to the carburetor.

7. Install the foam pre-cleaner onto the paper air filter.

   Note: Use a new paper air filter if you discarded the old one.

8. Install the air filter assembly and cover.

1. Run the engine to warm the engine oil.

   Note: Warm oil flows better and carries more contaminants.

   Warning

   Oil may be hot after engine has been run, and contact with hot oil can cause severe personal injury.

   Avoid contacting the hot engine oil when you drain it.

2. Stop the engine and wait for all moving parts to stop.

3. Disconnect the wire from the spark plug.

4. Place a drain pan on the ground to the right of the machine.

5. Remove the dipstick (Figure 25).

   

   Figure 25

6. Remove the drain plug (Figure 26) and tip the machine so the oil flows to the pan.

   

   Figure 26

   1. Oil drain plug
   2. Oil filter

7. Tip the machine upright again, clean the oil from the frame with a rap and replace the drain plug.

8. Insert the dipstick into the filler neck and rotate the cap clockwise until it is tight.

9. Slowly pour oil into the oil fill tube, periodically checking the level with the dipstick, until the dipstick indicates that the engine is full. Do not overfill. (Max. fill: 0.55 L (20 oz), type: SAE 30W detergent oil with an API service classification of SH, SJ, SL, or higher.)

   Note: If you overfill the engine, pour some oil out of it.

10. Install the dipstick securely.

11. Recycle the used oil according to local codes.

1. Drain the engine oil; refer to Changing the Engine Oil.

2. Place a rag under the oil filter (Figure 26) to catch any oil that may leak out as you remove the filter.

3. Remove the oil filter.

4. Use your finger to coat the gasket on the new filter with oil (Figure 27).

   

   Figure 27

5. Install the new filter and hand tighten it 2/3 turn only.

6. Insert the dipstick into the filler neck and rotate the cap clockwise until it is tight.

7. Slowly pour oil into the oil fill tube, periodically checking the level with the dipstick, until the dipstick indicates that the engine is full. Do not overfill. (Max. fill: 0.55 L (20 oz), type: SAE 30W detergent oil with an API service classification of SH, SJ, SL, or higher.)

   Note: If you overfill the engine, pour some oil out of it.

8. Install the dipstick securely.

9. Connect the wire to the spark plug.

10. Run the engine for about 3 minutes.

11. Stop the engine, wait for all moving parts to stop, and check for oil leakage around the filter.

12. Check and add oil to compensate for the oil in the oil filter. Do not overfill.

13. Recycle the used oil filter according to local codes.

Use an NGK BPR6ES spark plug or equivalent.

1. Stop the engine and wait for all moving parts to stop.

2. Disconnect the wire from the spark plug.

3. Clean around the spark plug.

4. Remove the spark plug from the cylinder head.

   Important: Replace a cracked, fouled, or dirty spark plug. Do not clean the electrodes because grit entering the cylinder can damage the engine.

5. Set the gap on the plug to 0.76 mm (0.030 inch) ().

   

   Figure 28

   1. Center electrode insulator
   2. Side electrode
   3. Air gap (not to scale)

6. Carefully install the spark plug by hand (to avoid cross threading) until it is hand tight.

7. Tighten the spark plug an additional 1/2 turn if it is new; otherwise, tighten it an additional 1/8 to 1/4 turn.

   Important: A loose spark plug can become very hot and can damage the engine; overtightening a spark plug may damage the threads in the cylinder head.

8. Connect the wire to the spark plug.

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Wait for the muffler to cool.

3. If you observe any breaks in the screen or welds, replace the spark arrester.

4. If you observe plugging of the screen, remove the spark arrester, shake the loose particles out of it, and clean the screen with a wire brush (soak in solvent if necessary). Replace the spark arrester when finished.

The fuel filter (screen) element is located inside the fuel tank.

1. Stop the engine and wait for it to cool down.

   Note: Drain gasoline for a cold engine only.

2. Disconnect the wire from the spark plug.

3. Close the fuel valve (Figure 29).

4. Disconnect the fuel line by loosening the tube clamp at the carburetor.

5. Open the fuel valve by turning the lever to the open position.

6. Drain the gasoline completely from the tank and fuel line into an approved fuel container.

7. Remove the fuel tank from the machine.

8. Close the fuel valve.

9. Pour a small amount of fuel in the fuel tank, move the fuel around in the tank, and pour it out into an approved fuel container.

10. Install the fuel tank and fuel line.

1. Stop the engine and wait for it to cool down.

   Important: Drain gasoline from a cold engine only.

2. Disconnect the wire from the spark plug.

3. Close the fuel valve.

4. Clamp off the fuel line on either side of the fuel filter (Figure 29) to prevent fuel from leaking out when you remove the filter.

   

   Figure 29

   1. Fuel filter
   2. Fuel valve

5. Squeeze the ends of the hose clamps together and slide them away from the filter (Figure 29).

6. Remove the filter from the fuel lines.

7. Install a new filter and move the hose clamps close to the filter (Figure 29).

8. Remove the clamps from the fuel lines.

9. Open the fuel shutoff valve.

Maintain the air pressure in the tires as specified. Check the tires when they are cold to get the most accurate reading.

Pressure: 83-97 kPa (12-14 psi)

Figure 30

1. Valve stem

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Raise the front of the machine to gain access to the chains and block it in place.

   Caution

   If you do not securely block the up the front of the machine, the machine could fall on you during service, injuring you.

   Ensure that you place a jackstand or block under the front of the machine to hold it up securely.

   Important: Do not raise the rear of the machine. Raising the rear of the machine will casue the engine to flood and the air cleaner to be fouled with gasoline.

3. Pull down on each chain near the opening in the frame with 9 kg (20 pounds) of force (Figure 31). If a chain flexes more than 3 mm (1/8 inch), tighten it as follows:

   

   Figure 31

   1. Flex in the chain

   1. Loosen the nut securing the idler sprocket of the chain you are tensioning (Figure 32).

      

      Figure 32

      1. Idler sprocket
      2. Nut

   2. Pull down on the idler sprocket until the slack is taken out of the chain.

   3. Tighten the idler sprocket nut and torque it to 40.6 N-m (30 ft-lb).

4. Repeat step 3 to test the chain tension and tighten it as needed.

5. Repeat this procedure for the other tine drive chain.

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Raise the front of the machine to gain access to the pump drive belt and block it in place.

   Caution

   If you do not securely block the up the front of the machine, the machine could fall on you during service, injuring you.

   Ensure that you place a jack stand or block under the front of the machine to hold it up securely.

   Important: Do not raise the rear of the machine. Raising the rear of the machine will cause the engine to flood and the air cleaner to be fouled with gasoline.

3. Push on a span of the drive belt with 9 kg (20 pounds) of force (Figure 33). If the belt flexes more than 3 mm (1/8 inch), tighten it as follows:

   

   Figure 33

   1. Pump drive belt
   2. Idler pulley
   3. Idler pulley nut

   1. Loosen the nut securing the idler pulley (Figure 33).

   2. Push the idler pulley to the left to tighten the belt .

   3. Tighten the idler pulley nut and torque it to 40.6 N-m (30 ft-lb).

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Squeeze the self-propel bail to the handle until the transmission is fully stroked.

   If the bail contacts the handle, release the bail. Loosen the top adjustment nut one turn and tighten the bottom adjustment nut. Squeeze the bail to the handle. Repeat this step until there is a gap (up to 3 mm (1/8 inch)) between the self–propel bail and the handle.

   

   Figure 34

   1. Self-propel drive bail
   2. Cable
   3. Top/Bottom adjustment nuts

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Drain the fuel from the fuel tank.

3. Slide the oval locking rings on the handle upward, and fold the handle towards the engine.

4. Slowly lift the front of the machine until the back of the machine and weight pockets are resting on the ground. Stabilize the machine with an overhead hoist.

   Note: Using two people or an overhead hoist to lift the machine will make this easier.

5. Remove the transmission from the machine (Figure 35).

   Note: It will take two people or a second hoist to safely remove the transmission.

   

   Figure 35

   1. Self-propel drive bail cable
   2. Idler pulley and transmission drive belt
   3. Front axle chain sprocket
   4. Drive chain
   5. Mounting hardware (7 locations)

   1. Disconnect the self-propel drive bail cable from the transmission.

   2. Remove the drive belt from the transmission pulley by loosening the nut on the idler pulley.

   3. Remove and retain the connecting link from the front axle chain sprocket, and remove the chain.

   4. Loosen the drive chain idler sprockets on each side of the unit. Remove and retain the connecting link from the drive chains, and remove the drive chain from the transmission sprockets.

   5. Support the transmission, remove and retain its mounting hardware, and carefully lower the transmission to the ground.

6. Carefully clean the area around the expansion tank and oil-fill port. It is important that no dirt or contamination enter the hydraulic system.

7. Remove and retain the oil-fill port fitting and position the transmission so the oil will drain completely out of the housing.

8. When all the oil has drained from the transmission, remove and retain the #10-32 x 1/2 inch self-tapping screw and ratchet fastener holding the expansion tank to the housing.

9. Remove the expansion tank and drain the oil.

   Note: Do not remove the vent cap from the tank.

   Note: Do not remove the tank hose or O-ring unless a replacement is needed.

10. Inspect the belt, pulleys, sprockets, and bearings; replace as required.

11. Install the previously removed expansion tank by first inserting the hose into the tank. Place the tank opening over the O-ring and push down to ensure a proper seal. Install the #10–32 x 1/2 inch self tapping screw and torque it to 2.8 N-m (25 in-lb).

12. Fill the transmission at the oil-fill port until the oil level is 13–32 mm (1/2–1 1/4 inches) below the top of the fill port.

    Toro Premium Hydro Oil is recommended. Mobil 1 15W50 is an acceptable alternative.

13. Install the previously removed oil-fill port fitting.

14. Install the previously removed transmission.

    1. With the transmission belt on the engine pulley and the idler pulley, loosely install the transmission using the previously removed mounting hardware.

    2. Install the transmission belt on the transmission pulley.

    3. Install the drive chains onto the idler and transmission sprockets.

    4. Install the chain on the front axle sprocket. Ensure that the front axle sprocket is aligned with the sprocket on the transmission.

    5. Tighten the 7 transmission mounting bolts.

    6. Tension the transmission belt; refer to Checking the Hydrostatic Drive Belt.

    7. Tension the tine drive chains; refer to Adjusting the Tension of Tine Drive Chains.

    8. Connect the self-propel drive bail cable.

15. Carefully remove the jackstands, lower the machine to the ground, and remove the overhead hoist hooks.

16. Raise and lock the handle into the operating position.

17. Check the gap between the handle and the bail. If the handle contacts the bail or if there is more than a 3mm (1/8 inch) gap, refer to Adjusting the Self-Propel Drive.

1. Raise the tines, stop the machine, stop the engine, and disconnect the spark plug wire.

2. Remove the rear access panel; refer to Accessing the Tines

3. Manually rotate the tines on the shaft, inspecting them for wear or damage.

4. If any are damaged or broken, remove the nut and bolt securing the tine to the tine assembly (Figure 36).

   

   Figure 36

   1. Tine assembly
   2. Tine
   3. Bolt and nut

5. Remove the tine and replace it with a new one. Ensure that the new tine is facing the same direction as the other tines on the assembly.

6. Secure the new tine with the bolt and nut you removed previously and torque them to 40.6 N-m (30 ft-lb).

7. When all tines have been inspected and replaced as needed, lower the machine to the ground and engage the hydrostatic drive.