Groundsmaster® 4500-D and 4700-D Traction Unit

Move the seat adjustment lever on the side of the seat outward, slide the seat to the desired position, and release the lever to lock the seat into position (Figure 13).

Figure 13

1. Weight gauge
2. Weight adjustment lever
3. Seat adjustment lever
4. Seat-back adjustment lever
5. Armrest adjustment knob

Rotate the knob to adjust the armrest angle (Figure 13).

Move the lever to adjust the seat-back angle (Figure 13).

The weight gauge indicates when the seat is adjusted to the weight of the operator (Figure 13). Adjust the height by positioning the suspension within the range of the green region.

Use this lever to adjust the seat to your weight (Figure 13). Pull the lever up to increase the air pressure and push the lever down to decrease the air pressure. The proper adjustment is correct when the weight gauge is in the green region.

Note: The factory default PIN code for your machine is either 0000 or 1234.If you changed the PIN code and forgot the code, contact your Authorized Toro Distributor for assistance.

1. From the MAIN MENU, use the center button to scroll down to the SETTINGS MENU and press the right button (Figure 15).

   

   Figure 15

2. In the SETTINGS MENU, use the center button to scroll down to the PROTECTED MENU and press the right button (Figure 16A).

   

   Figure 16

3. To enter the PIN code, press the center button until the correct first digit appears, then press the right button to move on to the next digit (Figure 16B and Figure 16C). Repeat this step until the last digit is entered and press the right button once more.

4. Press the middle button to enter the PIN code (Figure 16D).

   Wait until the red indicator light of the InfoCenter illuminates.

   Note: If the InfoCenter accepts the PIN code and the protected menu is unlocked, the word “PIN” displays in the upper right corner of the screen.

Note: Rotate the key switch to the OFF position and then to the ON position locks the protected menu.

You have the ability to view and change the settings in the Protected Menu. Once you access the Protected Menu, scroll down to Protect Settings option. Use the right button to change the setting. Setting the Protect Settings to OFF allows you to view and change the settings in the Protected Menu without entering the PIN code. Setting the Protect Settings to ON hides the protected options and requires you to enter the PIN code to change the setting in the Protected Menu. After you set the PIN code, rotate the key switch OFF and back to the ON position to enable and save this feature.

1. In the Protected Menu, scroll down to Protect Settings.

2. To view and change the settings without entering a PIN code, use the right button to change the Protect Settings to OFF.

3. To view and change the settings with a PIN code, use the left button to select ON, set the PIN code, and turn the key to the OFF position and then to the ON position.

1. In the Settings Menu, scroll down to Auto Idle.

2. Press the right button to change the auto idle time between Off, 8S, 10S, 15S, 20S, and 30S.

1. In the Settings Menu, scroll down to Mow Speed and press the right button.

2. Use the right button to increase the maximum mow speed in 5% increments between 50% and 100%.

3. Use the center button to decrease the maximum mow speed in 5% increments between 50% and 100%.

4. Press the left button to exit.

1. In the Settings Menu, scroll down to Transport Speed and press the right button.

2. Use the right button to increase the maximum transport speed in 5% increments between 50% and 100%.

3. Use the center button to decrease the maximum transport speed in 5% increments between 50% and 100%.

4. Press the left button to exit.

1. In the settings menu, scroll down to Smart Power.

2. Press the right button to switch between ON and OFF.

3. Press the left button to exit.

1. In the Settings Menu, scroll down to Counter Balance and press the right button.

2. Press the right button to switch between Low, Med, and High.

When finished with the Protected Menu, press the left button to exit to the Main Menu, then press the left button to exit to the Run Menu.

1. In the Settings Menu, scroll down to Turnaround.

2. Press the right button to switch between ON and OFF.

3. Press the left button to exit.

You can view the average fuel consumption rate for the lifetime of the machine in the Service Menu.

Before you start the engine and use the machine, check the oil level in the engine crankcase; refer to Checking the Engine-Oil Level.

Before you start the engine and use the machine, check the cooling system; refer to Checking the Cooling System.

Before you start the engine and use the machine, check the hydraulic system; refer to Checking the Hydraulic Lines and Hoses.

Drain water or other contaminants from the water separator; refer to Draining Water from the Fuel/Water Separator.

Check the rear axle and rear-axle gearbox for leaks; refer to Checking the Rear Axle and Gearbox for Leaks.

The correct air pressure in the tires is 138 kPa (20 psi).

Important: Maintain the recommended pressure in all tires to ensure a good quality of cut and proper machine performance. Do not under-inflate the tires.Check the air pressure in all the tires before operating the machine.

Figure 19

Torque the wheel lug nuts to 115 to 136 N∙m (85 to 100 ft-lb) in the order shown in Figure 20 and Figure 21.

Figure 20

Front Wheels

Figure 21

Rear Wheels

Important: Always use the seat belt when the roll bar is in the raised and locked position. Do not use the seat belt when the roll bar is in the lowered position.

Lowering the Roll Bar

Important: Lower the roll bar only when necessary.

Important: Ensure that the seat is secured with the seat latch.

Figure 22

Raising the Roll Bar

Figure 23

Important: The cutting units often cut approximately 6 mm (1/4 inch) lower than a reel cutting unit with the same bench setting. It may be necessary to set the cutting-unit bench measurement at 6 mm (1/4 inch) above that of reel cutting units cutting in the same area.

Important: Access to the rear cutting units is greatly improved by removing the cutting unit from the machine.

1. Park the machine on a level surface, engage the parking brake, lower the cutting unit to the ground, shut off the engine, and remove the key.

2. Loosen the bolt securing each height-of-cut bracket to the height-of-cut plate (front and each side) as shown in Figure 24.

3. Beginning with front adjustment, remove the bolt.

   

   Figure 24

   1. Height-of-cut bracket
   2. Height-of-cut plate
   3. Spacer

4. While supporting the chamber, remove the spacer (Figure 24).

5. Move the chamber to the desired height of cut and install a spacer into the designated height-of-cut hole and slot (Figure 25).

   

   Figure 25

6. Position the tapped plate in-line with the spacer.

7. Install the bolt finger-tight.

8. Repeat steps 4 through 7 for each side adjustment.

9. Torque all 3 bolts to 41 N∙m (30 ft-lb). Always tighten the front bolt first.

   Note: Adjustments of more than 3.8 cm (1-1/2 inches) may require temporary assembly to an intermediate height to prevent binding (e.g., changing from 3.1 to 7 cm (1-1/4 to 2-3/4 inches) height of cut).

The interlock switches are designed to shut off the machine when you rise from the seat when the traction pedal is pressed. However, you may rise from the seat while the engine is running and the traction pedal is in the NEUTRAL position. Although the engine continues to run when you disengage the PTO switch and release the traction pedal, shut off the engine before rising from the seat.

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, and turn the key to the OFF position.

2. Press the traction pedal and turn the key to the ON position.

   Note: If the engine cranks, there is a malfunction in the interlock system. Correct this malfunction before operating the machine.

3. Turn the key to the ON position, rise from the seat, and move the PTO switch to ON.

   Note: The PTO should not engage. If the PTO engages, there is a malfunction in the interlock system. Correct this malfunction before operating the machine.

4. Engage the parking brake, start the engine and allow the glow plugs to heat, then turn the key to the ON position and move the traction pedal out of the NEUTRAL position.

   Note: The InfoCenter displays "traction denied" and the machine should not move. If the machine does move, there is a malfunction in the interlock system. Correct this malfunction before operating the machine.

Note: Lower the cutting units onto a clean section of turf or hard surface to avoid throwing dust and debris.

To verify this stopping time, have someone stand back from the cutting units at least 6 m (20 ft) and watch the blades on 1 of the cutting units. Disengage the PTO and record the time it takes for the blades to come to a complete stop. If this time is greater than 7 seconds, adjust the braking valve. Call your authorized Toro distributor for assistance in making this adjustment.

Important: Bleed the fuel system if any of the following have occurred:

• The engine has shut off due to lack of fuel.

• Maintenance has been performed upon the fuel system components.

1. Remove your foot from the traction pedal and ensure that it is in NEUTRAL. Ensure that the parking brake is engaged.

2. Press down and hold the engine-speed switch to set the engine to low-idle speed.

3. Turn the key to the RUN position. The glow indicator should illuminate.

4. When the glow indicator dims, turn the key to the START position.

   Important: Do not run the starter motor more than 15 seconds at a time or premature starter failure may result. If the engine fails to start after 15 seconds, turn the key to the OFF position, check the controls and procedures, wait 15 additional seconds, and repeat the starting procedure.

5. Release the key immediately when the engine starts and allow it to return to the RUN position.

6. Press the engine-speed switch to set the desired engine speed.

   When the temperature is less than -7°C (20°F), the starter motor can be run for 30 seconds on then 60 seconds off for 2 attempts.

   Important: Shut off the engine and allow the engine to cool before you check for oil leaks, loose parts, or other malfunctions.

Important: Allow the engine to idle for 5 minutes before shutting it off after a full-load operation. This allows the turbocharger to cool down before shutting off the engine. Failure to do so may lead to turbocharger trouble.

Note: Lower the cutting units to the ground whenever machine is parked. This relieves the hydraulic load from the system, prevents wear on system parts and also prevents accidental lowering of the cutting units.

1. Press down and hold the engine-speed switch to set the engine to low-idle speed.

2. Move the PTO switch to the OFF position.

3. Engage the parking brake.

4. Rotate the ignition key to the OFF position.

5. Remove the key to prevent accidental starting.

Note: Cutting grass at a rate that loads the engine promotes DPF regeneration.

1. Move the machine to the job site and align the machine outside the cutting area for the first cutting pass.

2. Ensure that the PTO switch is set to the DISABLE position.

3. Move the lever for the mow-speed limiter forward.

4. Press the throttle-speed switch to set the engine speed to HIGH IDLE.

5. Use the joystick to lower the cutting units to the ground.

6. Press the PTO switch to prepare cutting units for operation.

7. Use the joystick to raise the cutting units off the ground.

8. Begin moving the machine toward the cutting area and lower the cutting units.

   Note: Cutting grass at a rate that loads the engine promotes DPF regeneration.

9. When you complete the mowing pass, use the joystick to lift the cutting units.

10. Perform a tear-shaped turn to quickly line up for your next pass.

The diesel particulate filter (DPF) is part of the exhaust system. The diesel-oxidation catalyst of the DPF reduces harmful gasses and the soot filter removes soot from the engine exhaust.

The DPF regeneration process uses heat from the engine exhaust to incinerate the soot accumulated on the soot filter, converting the soot to ash, and clears the channels of the soot filter so that filtered engine exhaust flows out the DPF.

The engine computer monitors the accumulation of soot by measuring the back pressure in the DPF. If the back pressure is too high, soot is not incinerating in the soot filter through normal engine operation. To keep the DPF clear of soot, remember the following:

• Passive regeneration occurs continuously while the engine is running—run the engine at full engine speed when possible to promote DPF regeneration.

• If the back pressure in the DPF is too high or a reset regeneration has not occurred for 100 hours, the engine computer signals you through the InfoCenter when reset regeneration is running.

• Allow the reset regeneration process to complete before shutting off the engine.

Operate and maintain your machine with the function of the DPF in mind. Engine load at high idle (full throttle) engine speed generally produces adequate exhaust temperature for DPF regeneration.

Important: Minimize the amount of time that you idle the engine or operate the engine at low-engine speed to help reduce the accumulation of soot in the soot filter.

DPF Soot Accumulation

• Over time, the diesel particulate filter accumulates soot in the soot filter. The computer for the engine monitors the soot level in the DPF.

• When enough soot accumulates, the computer informs you that it is time to regenerate the DPF.

• DPF regeneration is a process that heats the DPF to convert the soot to ash.

• In addition to the warning messages, the computer reduces the power produced by the engine at different soot-accumulation levels.

Engine Warning Messages—Soot Accumulation

Indication Level	Fault Code	Engine Power Rating	Recommended Action
Level 1: Engine Warning	Figure 26 Check EngineSPN 3719, FMI 16	The computer de-rates the engine power to 85%.	Perform a parked regeneration as soon as possible; refer to Parked or Recovery Regeneration.
Level 2: Engine Warning	Figure 27 Check EngineSPN 3719, FMI 0	The computer de-rates the engine power to 50%.	Perform a recovery regeneration as soon as possible; refer to Parked or Recovery Regeneration.

DPF Ash Accumulation

• The lighter ash is discharged through the exhaust system; the heavier ash collects in the soot filter.

• Ash is a residue of the regeneration process. Over time, the diesel particulate filter accumulates ash that does not discharge with the engine exhaust.

• The computer for the engine calculates the amount of ash accumulated in the DPF.

• When enough ash accumulates, the engine computer sends information to the InfoCenter in the form of an engine fault to indicate the accumulation of ash in the DPF.

• The fault messages indicate that it is time to service the DPF.

• In addition to the warnings, the computer reduces the power produced by the engine at different ash-accumulation levels.

InfoCenter Advisory and Engine Warning Messages—Ash Accumulation

Indication Level	Fault Code	Engine Speed Reduction	Engine Power Rating	Recommended Action
Level 1: Engine Warning	Figure 28 Check EngineSPN 3720, FMI 16	None	The computer de-rates the engine power to 85%.	Service the DPF; refer to Servicing the Diesel-Oxidation Catalyst (DOC) and the Soot Filter
Level 2: Engine Warning	Figure 29 Check EngineSPN 3720, FMI 16	None	The computer de-rates the engine power to 50%.	Service the DPF; refer to Servicing the Diesel-Oxidation Catalyst (DOC) and the Soot Filter
Level 3: Engine Warning	Figure 30 Check EngineSPN 3251, FMI 0	Engine speed at maximum torque + 200 rpm	The computer de-rates the engine power to 50%.	Service the DPF; refer to Servicing the Diesel-Oxidation Catalyst (DOC) and the Soot Filter

Types of Diesel Particulate Filter Regeneration

Types of diesel particulate filter regeneration that are performed while the machine is operating:

Type of Regeneration	Conditions that cause DPF regeneration	DPF description of operation
Passive	Occurs during normal operation of the machine at high-engine speed or high-engine load	• The InfoCenter does not display an icon indicating passive regeneration.
		• During passive regeneration, the DPF processes high-heat exhaust gasses, oxidizing harmful emissions, and burning soot to ash.
		Refer to .
Assist	Occurs because of low-engine speed, low-engine load, or after the computer detects the DPF is becoming obstructed with soot	• The InfoCenter does not display an icon indicating assist regeneration.
		• During assist regeneration, the engine computer adjusts the engine settings to raise the exhaust temperature.
		Refer to Assist DPF Regeneration.
Reset	Occurs every 100 hours	• When the high exhaust-temperature icon is displayed in the InfoCenter, a regeneration is in progress.
	Also occurs after assist regeneration only if the computer detects that assist regeneration did not sufficiently reduce the soot level
		• During reset regeneration, the engine computer adjusts the engine settings to raise the exhaust temperature.
		Refer to Reset Regeneration.

Types of diesel particulate filter regeneration that require you to park the machine:

Type of Regeneration	Conditions that cause DPF regeneration	DPF description of operation
Parked	Occurs because the computer detects back pressure in the DPF due to soot buildup	• When the reset-standby/parked or recovery regeneration icon or ADVISORY #188 displays in the InfoCenter, a regeneration is requested.
	Also occurs because the operator initiates a parked regeneration
	May occur because you set the InfoCenter to inhibit reset regeneration and continued operating the machine, adding more soot when the DPF already needs a reset regeneration	• Perform the parked regeneration as soon as possible to avoid needing a recovery regeneration.
	May result from using the incorrect fuel or engine oil	• A parked regeneration requires 30 to 60 minutes to complete.
		• You must have at least a 1/4 tank of fuel in the tank.
		• You must park the machine to perform a parked regeneration.
		Refer to Parked or Recovery Regeneration.
Recovery	Occurs because the operator ignored requests for a parked regeneration and continued operating the machine, adding more soot to the DPF	• When the reset-standby/parked or recovery regeneration icon or ADVISORY #190 displays in the InfoCenter, a recovery regeneration is requested.
		• A recovery regeneration requires up to 3 hours to complete.
		• You must have at least a 1/2 tank of fuel in the machine.
		• You must park the machine to perform a recovery regeneration.
		Refer to Parked or Recovery Regeneration.

Accessing the DPF Regeneration Menus

Accessing the DPF Regeneration Menus

1. Access the Service menu, press the center button to scroll down to the DPF REGENERATION option (Figure 31).

   

   Figure 31

2. Press the right button to select the DPF Regeneration entry (Figure 31).

Time Since Last Regeneration

Access the DPF Regeneration menu, press the center button to scroll down to the LAST REGEN field (Figure 32).

Use the LAST REGEN field to determine how many hours you have run the engine since the last reset, parked, or recovery regeneration.

Figure 32

Technician Menu

Important: For operating convenience, you may decide to perform a parked regeneration before the soot load reaches 100%, provided the engine has run more than 50 hours since the last successful reset, parked, or recovery regeneration.

Use the technician menu to view the current state of engine regeneration control and view the reported soot level.

Access the DPF Regeneration menu, press the center button to scroll down to the TECHNICIAN option, and press the right button to select the Technician entry (Figure 33).

Figure 33

• Use the DPF operation table to understand the current state of DPF operation (Figure 34).

  

  Figure 34

  .

  DPF Operation Table

  State	Description
  Normal	The DPF is in normal-operating mode—passive regeneration.
  Assist Regen	The engine computer is performing an assist regeneration.
  Reset Stby	The engine computer is trying to run a reset regeneration, but 1 of the following conditions prevents regeneration:	The regen inhibit setting is set to ON.
  		The exhaust temperature is too low for regeneration.
  Reset Regen	The engine computer is running a reset regeneration.
  Parked Stby	The engine computer is requesting that you run a parked regeneration.
  Parked Regen	You initiated a parked regeneration request and the engine computer is processing the regeneration.
  Recov. Stby	The engine computer is requesting that you run a recovery regeneration.
  Recov. Regen	You initiated a recovery regeneration request and the engine computer is processing the regeneration.

• View the soot load which is measured as the percentage of soot in the DPF(Figure 35); refer to the soot-load table.

  Note: The soot load value varies as the machine is operated and DPF regeneration occurs.

  

  Figure 35

  Soot-Load Table

  Important Soot Load Values	Regeneration State
  0% to 5%	Minimum soot load range
  78%	The engine computer performs an assist regeneration.
  100%	The engine computer automatically requests a parked regeneration.
  122%	The engine computer automatically requests a recovery regeneration.

Reset Regeneration

Caution

The exhaust temperature is hot (approximately 600°C (1,112°F) during DPF regeneration. Hot exhaust gas can harm you or other people.

• Never operate the engine in an enclosed area.

• Make sure that there are no flammable materials around the exhaust system.

• Never touch a hot exhaust system component.

• Never stand near or around the exhaust pipe of the machine.

Figure 36

• The high exhaust-temperature icon displays in the InfoCenter (Figure 36).

• The engine computer adjusts engine settings to raise the exhaust temperature.

  Important: The high exhaust-temperature icon indicates that the exhaust temperature discharged from of your machine may be hotter than during regular operation.

• While operating the machine, run the engine at full engine speed and high load when possible to promote DPF regeneration.

• The icon displays in the InfoCenter while the reset regeneration is processing.

• Whenever possible, do not shut off the engine or reduce engine speed while the reset regeneration is processing.

  Important: Whenever possible, allow the machine to complete the reset regeneration process before shutting off the engine.

Periodic Reset Regeneration

If the engine has not completed a successful Reset, Parked, or Recovery regeneration in the previous 100 hours of engine operation, the engine computer will attempt to perform a reset regeneration.

Setting the Inhibit Regen

Reset Regeneration Only

Note: If you set the InfoCenter to inhibit regeneration, the InfoCenter displays ADVISORY #185 (Figure 37) every 15 minutes while the engine requests a reset regeneration.

Figure 37

A reset regeneration produces the elevated engine exhaust. If you are operating the machine around trees, brush, tall grass, or other temperature-sensitive plants or materials, you can use the Inhibit Regen setting to prevent the engine computer from performing a reset regeneration.

Important: When you shut off the engine and start it again, the inhibit regen setting defaults to OFF.

1. Access the DPF Regeneration menu, press the center button to scroll down to the INHIBIT REGEN option, and press the right button to select the Inhibit Regen entry (Figure 38).

   

   Figure 38

2. Press the right button to change the inhibit regeneration setting from On to Off (Figure 38) or from Off to On (Figure 39).

   

   Figure 39

Allowing a Reset Regeneration

The InfoCenter displays the high exhaust-temperature icon when the reset regeneration is in process.

Note: If INHIBIT REGEN is set to ON, the InfoCenter displays ADVISORY #185 (Figure 40). Press button 3 to set inhibit regeneration setting to OFF and continue with the reset regeneration.

Figure 40

Note: If the engine exhaust temperature is too low, the InfoCenter displays ADVISORY #186 (Figure 41) to inform you to set the engine to full throttle (high idle).

Figure 41

Note: When the reset regeneration completes, the high exhaust-temperature disappears from the InfoCenter screen.

Practice driving the machine because it has a hydrostatic transmission, and its characteristics are different than many turf maintenance machines.

Smart Power prevents bogging down in heavy turf by automatically controlling the machine speed and optimizing cutting performance.

You can use the brakes to assist in turning the machine. However, use them carefully, especially on soft or wet grass because the turf may be torn accidentally. The brakes can also help you to maintain traction. For example, on some slopes, the uphill wheel can slip and lose traction. In this situation, press the uphill turn pedal gradually and intermittently until the uphill wheel stops slipping, thus increasing traction on the downhill wheel.

Use extra care when operating the machine on slopes. Make sure that the seat latch is properly secured and that the seat belt is buckled. Drive slowly and avoid sharp turns on slopes to prevent rollovers. For steering control, lower the cutting units when going downhill.

Important: Allow the engine to idle for 5 minutes before shutting it off after a full load operation. This allows the turbo charger to cool down before shutting the engine off. Failure to do so may damage the turbo-charger.

Before shutting off the engine, disengage all controls and set the engine speed to slow to reduce the engine speed to slow reduces high engine speed (rpm), noise, and vibration. Turn the key to the OFF position to shut off the engine.

The engine cooling fan is normally controlled by the machine. The machine can reverse the fan to blow debris off the rear screen. Under normal operating conditions, the machine controls the fan speed and direction based on coolant and hydraulic-fluid temperature, and the fan automatically reverses direction to blow debris off the rear screen. A reverse cycle is automatically initiated when either the coolant or hydraulic-fluid temperature reaches a specific temperature.

You can manually reverse the fan by pressing the 2 outer buttons of the InfoCenter for 2 seconds—the fan completes a manually initiated reverse cycle. Reverse the fan when the rear screen is clogged or prior to moving the machine into the shop or a storage area.

Figure 62

The cruise-control switch locks in the pedal position to maintain the desired ground speed. Pressing the rear of the switch turns the cruise control off, the middle position of the switch enables the cruise-control function, and the front of the switch sets the desired ground speed.

Note: Pressing either the brake pedal or moving the traction pedal into the REVERSE position, for 1 second, also disengages the pedal position.

Use the 2 rear-transport latches for the No. 6 and 7 mower decks when moving the machine over long distances, rough terrain, when transporting, or storing the machine.

Figure 63

Use the cutting-unit storage lanyards to prevent the forward outer cutting units from settling when the machine is parked overnight or if it is being stored for an extensive period. You can also use the cutting-unit storage lanyards to prevent the cutting units from floating while the machine is transporting between mowing tasks.

Figure 64

Stowing the Lanyards

Note: Stow the lanyards when you are not using them.

1. Ensure that the PTO is disengaged.

2. Park the machine on a level surface.

3. Engage the parking brake.

4. With the cutting units lowered, slip the loop of the lanyard into the slot in the reinforcement plate of the roller support (Figure 66).

Figure 66

1. Reinforcement-plate slot (roller support)
2. Lanyard loop

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

• Use full-width ramps for loading the machine into a trailer or a truck.

• Tie the machine down securely.

In an emergency, the machine can be moved forward by actuating the bypass valve in the variable-displacement hydraulic pump and pushing or towing the machine.

Important: Do not push or tow the machine faster than 3 to 4.8 km/h (2 to 3 mph), because you may damage the transmission. The bypass valves must be open whenever you push or tow the machine.

1. Open the hood and locate the bypass valves (Figure 67) on the top of pump, behind the battery and storage boxes.

   

   Figure 67

   1. Bypass valves

2. Rotate each valve 3 turns counter-clockwise to open and allow the oil to bypass internally.

   Note: Do not open more than 3 turns. Because fluid is bypassed, you can slowly move the machine without damaging the transmission.

3. Close the bypass valves before starting the engine.

4. Torque to 70 N∙m (52 ft-lb) to close the valve.

Important: To push or tow the machine in reverse, you must bypass the check valve in the 4-wheel drive manifold. To bypass the check valve, connect a hose assembly to the reverse traction pressure test port, located on the hydrostat, and on the port located between ports M8 and P2 on the rear traction manifold, which is located behind the front tire. The hose assembly includes 1 hose (Part No. 95-8843), 2 coupler fittings (Part No. 95-0985), and 2 hydraulic fittings (Part No. 340-77).

Note: Use properly-rated DOT-approved straps in 4 corners to tie down the machine.

• On each side of the frame by the operator’s platform

• On the rear bumper

Figure 68

Figure 69

1. Ensure that the PTO is disengaged.

2. Park the machine on a level surface.

3. Engage the parking brake.

4. Lower the cutting unit(s) if necessary.

5. Shut off the engine and wait for all moving parts to stop.

6. Turn the key to the STOP position and remove it.

7. Allow machine components to cool before performing maintenance.

Use the following as points to lift the machine:

Front of the machine—at the frame of the machine, forward of the wheel-drive motors (Figure 71)

Important: Do not support the machine at the wheel-drive motors. Keep the lifting equipment clear of hydraulic tubing and hoses.

Figure 71

Rear of the machine—at the center of the axle (Figure 72)

Locate the jackstands of the specified capacity at both sides of the gear case and under the axle.

Important: Do not support the machine at the tie rod.

Figure 72

Tilt the hood to access the chassis as shown in Figure 73.

Figure 73

Tilt the seat to access the hydraulic lift compartment as shown in Figure 74.

Figure 74

Grease specification: No. 2 lithium grease

The grease fitting locations and quantities are as follows:

• Brake-shaft pivot bearings (5) as shown in Figure 75

  

  Figure 75

• Rear-axle-pivot bushings (2) as shown in Figure 76)

  

  Figure 76

• Steering-cylinder ball joints (2) as shown in Figure 77

  

  Figure 77

  1. Top fitting on kingpin

• Tie-rod ball joints (2) as shown in Figure 77

• Kingpin bushings (2) as shown in Figure 77

  Important: Lubricate the top fitting on the kingpin no more than annually (2 pumps).

• Lift-arm bushings (1 per cutting unit) as shown in Figure 78

  

  Figure 78

• Lift-cylinder bushings (2 per cutting unit) as shown in Figure 78

• Cutting-unit spindle-shaft bearings (2 per cutting unit) as shown in Figure 79

  Note: You can use either fitting, whichever is more accessible. Pump grease into the fitting until a small amount appears at the bottom of the spindle housing (under the cutting unit).

  

  Figure 79

• Cutting-unit carrier-arm bushings (1 per cutting unit) as shown in Figure 79

• Rear roller bearings (2 per cutting unit) as shown in Figure 80

  

  Figure 80

  Important: Make sure that the grease groove in each roller mount aligns with the grease hole in each end of the roller shaft. To help align the groove and the hole, there is also an alignment mark on 1 end of the roller shaft.

Check the air-cleaner body for damage which could cause an air leak. Replace it if it is damaged. Check the whole intake system for leaks, damage, or loose hose clamps.

Service the air-cleaner filter only when the service indicator (Figure 81) requires it. Changing the air filter before it is necessary only increases the chance of dirt entering the engine when you remove the filter.

Figure 81

1. Air-cleaner indicator

Important: Be sure that the cover is seated correctly and seals with the air-cleaner body.

1. Replace the air cleaner (Figure 82).

   

   Figure 82

   Note: Do not clean a used element because cleaning it can damage the filter media.

   Important: Never attempt to clean the safety filter (Figure 83). Replace the safety filter after every 3 primary filter services.

   

   Figure 83

   1. Air-cleaner safety filter

2. Reset the indicator (Figure 81) if it shows red.

If engine faults , , or display in the InfoCenter(Figure 86), clean the soot filter using the steps that follow:

Figure 86

1. Refer to the Engine section in the Service Manual for information on disassembling and assembling the diesel-oxidation catalyst and the soot filter of the DPF.

2. Refer to your authorized Toro distributor for diesel-oxidation catalyst and the soot filter replacement parts or service.

3. Contact your authorized Toro distributor to reset the engine ECU after you install a clean DPF.

Drain and clean the tank also if the fuel system becomes contaminated or if you are storing the machine for an extended period. Use clean fuel to flush out the tank.

Inspect the fuel lines and connections for deterioration, damage, or loose connections.

1. Clean the area around the fuel-filter head (Figure 90).

   

   Figure 90

   1. Fuel-filter head
   2. Fuel filter

2. Remove the filter and clean the filter head mounting surface (Figure 90).

3. Lubricate the filter gasket with clean lubricating engine oil; refer to the engine owner's manual for additional information.

4. Install the dry filter canister, by hand, until the gasket contacts the filter head, then rotate it an additional 1/2 turn.

5. Start the engine and check for fuel leaks around the filter head.

The fuel-pickup tube, located inside the fuel tank, is equipped with a screen to help prevent debris from entering the fuel system. Remove the fuel-pickup tube and clean the screen as required.

1. Remove the hose clamp that secures the fuel supply hose to the fitting of the fuel-pickup tube (Figure 91).

   

   Figure 91

   1. Fitting (fuel-pickup tube)
   2. Hose clamp
   3. Fuel supply hose
   4. Rubber bushing
   5. Screen

2. Separate the hose from the fitting (Figure 91).

3. Lift the fuel-pickup tube from the fuel tank (Figure 91).

   Note: Lift the tube straight from the bushing in the tank.

4. Clean any debris from the screen at the end of the fuel-pickup tube (Figure 91).

5. Insert the fuel-pickup tube through the rubber bushing and into the tank (Figure 91).

   Note: Ensure that the fuel-pickup tube is fully seated into the rubber bushing.

6. Install the supply hose onto the fitting of the fuel-pickup tube, and secure the hose with the hose clamp that you removed in step 1.

Prime the fuel system before starting the engine for the first time, after running out of fuel, or after fuel system maintenance (e.g., draining the filter/water separator, replacing a fuel hose).

To prime the fuel system, perform the following steps:

1. Ensure that fuel is in the fuel tank.

2. Turn the ignition key to the ON position for 10 to 15 seconds.

   Note: This allows the fuel pump to prime the fuel system.

Important: Do not use the engine starter motor to crank the engine to prime the fuel system.

Important: Before welding on the machine, disconnect the negative cable from the battery to prevent damage to the electrical system. Also, you must disconnect the engine, InfoCenter, and machine controllers before welding on the machine.

Note: Keep the terminals and the entire battery case clean, because a dirty battery discharges slowly. To clean the battery, wash the entire case with a solution of baking soda and water. Rinse with clear water. Coat the battery posts and cable connectors with Grafo 112X (skin-over) grease (Toro Part No. 505-47) or petroleum jelly to prevent corrosion.

1. Unlatch and raise the operator's console panel (Figure 92).

   

   Figure 92

   1. Operator's console panel
   2. Latch

   Danger

   Battery electrolyte contains sulfuric acid, which is fatal if consumed and causes severe burns.

   • Do not drink electrolyte and avoid contact with skin, eyes, or clothing. Wear safety glasses to shield your eyes and rubber gloves to protect your hands.

   • Fill the battery where clean water is always available for flushing the skin.

2. Remove the rubber boot from the positive terminal and inspect the battery.

3. Remove the negative cable (black) from the negative (-) terminal and the positive cable (red) from the positive (+) terminal of the battery (Figure 93).

   Warning

   Incorrect battery cable routing could damage the machine and cables, causing sparks. Sparks can cause the battery gasses to explode, resulting in personal injury.

   • Always disconnect the negative (black) battery cable before disconnecting the positive (red) cable.

   • Always connect the positive (red) battery cable before connecting the negative (black) cable.

   Warning

   Battery terminals or metal tools could short against metal components, causing sparks. Sparks can cause the battery gasses to explode, resulting in personal injury.

   • When removing or installing the battery, do not allow the battery terminals to touch any metal parts of the machine.

   • Do not allow metal tools to short between the battery terminals and metal parts of the machine.

   

   Figure 93

   1. Positive battery cable
   2. Negative battery cable

4. Connect a 3 to 4 A battery charger to the battery posts. Charge the battery at a rate of 3 to 4 A for 4 to 8 hours.

   Warning

   Charging the battery produces gasses that can explode.

   Never smoke near the battery and keep sparks and flames away from battery.

5. When the battery is charged, disconnect the charger from the power outlet and battery posts.

6. Install the positive cable (red) to the positive (+) terminal and the negative cable (black) to the negative (-) terminal of the battery (Figure 93).

7. Secure the cables to the posts with bolts and nuts.

   Note: Make sure that the positive (+) terminal is all the way on the post and the cable is positioned snug to the battery. The cable must not contact the battery cover.

8. Coat both battery connections with Grafo 112X (skin-over) grease, Part No. 505-47, petroleum jelly, or light grease to prevent corrosion.

9. Slide the rubber boot over the positive terminal.

10. Close the console panel and secure the latch.

The fuse block for the machine is located in the right storage box

Figure 94

1. Loosen the latch for the cover of the right storage box and raise the cover (Figure 95) to expose the fuse block (Figure 96).

   

   Figure 95

   1. Latch
   2. Right storage box

2. Replace the open fuse(s) as needed (Figure 96).

   

   Figure 96

   1. Fuses

3. Close the cover of the right storage box and secure the cover with the latch (Figure 95).

There should be no end-play in the planetary drives/drive wheels (i.e., the wheels should not move when you pull or push them in a direction parallel to the axle).

1. Park the machine on a level surface, engage the parking brake, lower the cutting units, shut off the engine, and remove the key.

2. Chock the rear wheels and raise the front of machine, supporting the front axle/frame on jack stands.

   Danger

   A machine on a jack may be unstable and slip off the jack, injuring anyone beneath it.

   • Do not start the engine while the machine is on a jack.

   • Always remove the key from the switch before getting off the machine.

   • Block the tires when you are raising the machine with a jack.

   • Support the machine with jack stands.

3. Grasp 1 of the front drive wheels and push/pull it toward and away from the machine, noting any movement.

   

   Figure 98

   1. Front drive wheels

4. Repeat step 3 for the other drive wheel.

5. If either wheel moves, contact your authorized Toro distributor to have the planetary drive rebuilt.

Lubricant Specification: high quality SAE 85W-140 gear lubricant

1. Park the machine on level surface, position the wheel so that the fill plug is at the 12 o'clock position, the check plug is at 3 o'clock position, and the drain plug is at the 6 o'clock position (Figure 99).

   

   Figure 99

   1. Fill plug (12 o’clock position)
   2. Check plug (3 o’clock position)
   3. Drain plug (6 o’clock position)

2. Remove the check plug at the 3 o’clock position (Figure 99).

   The oil level should be at the bottom of the check-plug hole.

   

   Figure 100

   1. Check-plug hole
   2. Check plug

3. If the oil level is low, remove the fill plug at the 12 o’clock position and add oil until it begins to flow out of the hole at the 3 o’clock position.

4. Check the O-ring for the plug(s) for wear or damage.

   Note: Replace the O-ring(s) as needed.

5. Install the plug(s).

6. Repeat steps 1 through 5 on the planetary gear assembly at the other side of the machine.

Lubricant specification: high quality SAE 85W-140 gear lubricant

Planetary and brake housing lubrication capacity: 0.65 L (22 fl oz)

Visually inspect the rear axle and rear-axle gearbox for leaks.

Figure 105

The rear axle is filled with SAE 85W-140 gear lube. The capacity is 2.4 L (80 fl oz). Visually inspect for leaks daily.

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Remove a check plug from 1 end of the axle and ensure that the lubricant is up to the bottom of the hole (Figure 106).

   Note: If the level is low, remove the fill plug and add enough lubricant to bring the level up to the bottom of the check-plug holes.

   

   Figure 106

   1. Check plug
   2. Fill plug

Lubricant specification: high-quality SAE 85W-140 gear lubricant

Axle capacity: 2.4 L (80 fl oz)

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Clean the area around the 3 drain plugs—1 on each end and 1 in the center (Figure 107).

   

   Figure 107

   1. Drain-plug location

3. Remove the oil-level check plugs and the main-axle-vent cap to ease draining the gear lubricant.

4. Remove the drain plugs and allow the gear lubricant to drain into the pans.

5. Install the plugs.

6. Remove a check plug and fill the axle with approximately 2.4 L (80 fl oz) of 85W-140 gear lube or until the lubricant is up to the bottom of the hole.

7. Install the check plug.

The gear box is filled with SAE 85W-140 gear lube. The capacity is 0.5 L (16 fl oz). Visually inspect for leaks daily.

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Remove the check/fill plug from the left side of the gear box and ensure that lubricant is up to the bottom of the hole (Figure 108).

   Note: If the level is low, add enough lubricant to bring the level up to the bottom of the hole.

   

   Figure 108

   1. Gearbox
   2. Check/fill plug

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Measure the center-to-center distance (at axle height) at the front and rear of the steering tires (Figure 109).

   Note: The front measurement must be 3 mm (1/8 inch) less than the rear measurement.

   

   Figure 109

   1. Front of the machine
   2. 3 mm (1/8 inch) less than the rear measurement
   3. Center to center distance

3. To adjust, remove the cotter pin and nut from either tie rod ball joint (Figure 110). Remove the tie-rod ball joint from the axle-case support.

   

   Figure 110

   1. Tie-rod clamp
   2. Tie-rod ball joint

4. Loosen the clamps at both ends of the tie rods (Figure 110).

5. Rotate the detached ball joint inward or outward 1 complete revolution and tighten the clamp at the loose end of the tie rod.

6. Rotate the entire tie-rod assembly the same direction (inward or outward) 1 complete revolution and tighten the clamp at the connected end of the tie rod.

7. Install the ball joint in the axle-case support, tighten the nut finger-tight, and measure the toe-in.

8. Repeat procedure if necessary.

9. Tighten the nut and install a new cotter pin when the adjustment is correct.

Coolant specification: 50/50 mixture of water and ethylene glycol antifreeze

Cooling system capacity: 8.5 L (9 US qt).

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Carefully remove the radiator cap.

   Caution

   If the engine has been running, the pressurized, hot coolant can escape and cause burns.

   • Do not open the radiator cap when the engine is running.

   • Use a rag when opening the radiator cap, and open the cap slowly to allow steam to escape.

   

   Figure 111

   1. Expansion tank

3. Check the coolant level in the radiator. The radiator should be filled to the top of the filler neck and the expansion tank filled to the FULL mark (Figure 111).

4. If the coolant is low, add a 50/50 mixture of water and ethylene glycol anti-freeze. Do not use water only or alcohol/methanol based coolants.

5. Install the radiator cap and expansion-tank cap.

This machine is equipped with a hydraulically driven fan drive system that automatically (or manually) reverses to reduce oil cooler/radiator and screen debris buildup. While this feature can help reduce the time required to clean oil cooler/radiator, it does not eliminate the need for routine cleaning. Periodic cleaning and inspection of the radiator/cooler is still required.

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Unlatch and swing open the rear screen (Figure 112).

   Note: To remove the screen, lift it off the hinge pins.

3. Clean the screen thoroughly of all debris.

   

   Figure 112

   1. Rear-screen latch

4. Thoroughly clean both sides of the oil cooler and the radiator with compressed air (Figure 113).

   Note: Start from the front and blow the debris out toward the back. Then clean from the back side and blow toward the front. Repeat procedure several times until you remove all chaff and debris.

   

   Figure 113

   1. Oil cooler/radiator

   Important: Cleaning the oil cooler/radiator with water promotes premature corrosion damage to components and compacts debris.

5. Close the rear screen and secure it with the latch.

Adjust the service brakes when there is more than 25 mm (1 inch) of free travel of the brake pedal, or when the brakes do not work effectively. Free travel is the distance the brake pedal moves before you feel braking resistance.

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Release the locking latch from the brake pedals so that both pedals work independently of each other.

3. To reduce free travel of the brake pedals, tighten the brakes as follows:

   1. Loosen the front nut on the threaded end of the brake cable (Figure 114).

      

      Figure 114

      1. Brake cable

   2. Tighten the rear nut to move the cable rearward until the brake pedals have 13 to 25 mm (1/2 to 1 inch) of free travel.

   3. Tighten the front nuts after the brakes are adjusted correctly.

Proper tension of the belt allows 10 mm (3/8 inch) of deflection when a force of 4.5 kg (10 lb) is applied on the belt midway between the pulleys.

If the deflection is not 10 mm (3/8 inch), loosen the alternator-mounting bolts (Figure 115).

Note: Increase or decrease the alternator-belt tension and tighten the bolts. Check the deflection of the belt again to ensure that the tension is correct.

Figure 115

1. Mounting bolt
2. Alternator

The reservoir is filled at the factory with approximately 28.4 L (7.50 US gallons) of high-quality hydraulic fluid. Check the level of the hydraulic fluid before the engine is first started and daily thereafter. The recommended replacement fluid is as follows:

Toro Premium All Season Hydraulic Fluid (Available in 19 L (5 US gallon) pails or 208 L (55 US gallon) drums. See the Parts Catalog or your authorized Toro distributor for part numbers).

Alternative fluids: If the Toro fluid is not available, other conventional, petroleum-based fluids may be used, provided they meet all the following material properties and industry specifications. Check with your oil supplier to see whether the oil meets these specifications.

Note: Toro does not assume responsibility for damage caused by improper substitutions, so use only products from reputable manufacturers who will stand behind their recommendation.

High Viscosity Index/Low Pour Point Anti-Wear Hydraulic Fluid, ISO VG 46

Important: The ISO VG 46 Multigrade fluid has been found to offer optimal performance in a wide range of temperature conditions. For operation in consistently high ambient temperatures, 65°F (18°C) to 120°F (49°C), ISO VG 68 hydraulic fluid may offer improved performance.

Premium Biodegradable Hydraulic Fluid-Mobil EAL EnviroSyn 46H

Important: Mobil EAL EnviroSyn 46H is the only synthetic biodegradable fluid approved by Toro. This fluid is compatible with the elastomers used in Toro hydraulic systems and is suitable for a wide-range of temperature conditions. This fluid is compatible with conventional mineral oils, but for maximum biodegradability and performance the hydraulic system should be thoroughly flushed of conventional fluid. The fluid is available in 19 L (5 US gallon) containers or 208 L (55 US gallon) drums from your Mobil Distributor.

Important: Many hydraulic fluids are almost colorless, making it difficult to spot leaks. A red dye additive for the hydraulic system fluid is available in 20 ml (0.67 oz) bottles. A bottle is sufficient for 15 to 22 L (4 to 6 US gallons) of hydraulic fluid. Order Part No. 44-2500 from your authorized Toro distributor.

1. Park the machine on a level surface, engage the parking brake, lower the cutting units, shut off the engine, and remove the key.

2. Check the hydraulic-fluid level (Figure 116).

   

   Figure 116

If the fluid becomes contaminated, contact your Toro Distributor because the system must be flushed. Contaminated fluid looks milky or black when compared to clean oil.

1. Park the machine on a level surface, engage the parking brake, lower the mower decks, shut off the engine, and remove the key.

2. Raise the hood.

3. Disconnect the case return line from the bottom of the reservoir and let the hydraulic fluid flow into a large drain pan.

4. Install the hose when the hydraulic fluid stops draining.

5. Fill the reservoir with hydraulic fluid; refer to Checking the Hydraulic-Fluid Level.

   Important: Use only the hydraulic fluids specified. Other fluids could cause system damage.

6. Install the reservoir cap.

7. Turn the key in the key switch to the ON position to start the engine. Use all the hydraulic controls to distribute hydraulic fluid throughout the system, and check for leaks.

8. Turn the key in the key switch to the OFF position.

9. Check the fluid level and add enough to raise level the level to the FULL mark on the dipstick. Do not overfill.

Use Toro replacement filters Part No. 94-2621 for the rear (mower decks) of the machine and Part No. 75-1310 for the front (charge) of the machine.

Important: Use of any other filter may void the warranty on some components.

1. Tilt the operator’s seat to access the mower pressure filter; refer to Accessing the Hydraulic Lift Compartment

   

   Figure 117

2. Replace the charge hydraulic filter at the hydraulic lift compartment as shown in Figure 118.

   

   Figure 118

3. Lower and secure the operator’s seat.

4. Replace the return filter at the right side of the machine (Figure 118).

5. Start the engine and let it run for about 2 minutes to purge air from the system. Shut off the engine and check for leaks.

Inspect the hydraulic lines and hoses daily for leaks, kinked lines, loose mounting supports, wear, loose fittings, weather deterioration, and chemical deterioration. Make all necessary repairs before operating the machine.

1. Park the machine on a level surface, engage the parking brake, lower the cutting units, shut off the engine, and remove the key.

2. Disconnect and remove the hydraulic motor from the cutting unit (Figure 119). Cover the top of the spindle to prevent contamination.

   

   Figure 119

   1. Motor-mounting screws

3. Remove the lynch pin (for Groundsmaster 4500 machines) or retaining nut (for Groundsmaster 4700 machines) securing the cutting unit-carrier frame to the lift-arm pivot pin (Figure 120).

   

   Figure 120

   1. Lynch pin
   2. Lift-arm pivot pin

4. Roll the cutting unit away from the machine.

1. Move the cutting unit into position in front of the machine.

2. Slide the cutting unit-carrier frame onto the lift-arm-pivot pin (Figure 120). Secure the cutting unit to the pin with the lynch pin (for Groundsmaster 4500 machines) or retaining nut (for Groundsmaster 4700 machines).

3. Install the hydraulic motor to the cutting unit (Figure 119). Make sure that the O-ring is in position and not damaged.

4. Grease the spindle.

Inspect the front roller for wear, excess wobble, or binding. Service or replace the roller or components if any of these conditions exist.

The cutting unit comes from the factory preset at 5 cm (2 inches) height of cut and blade rake of 7.9 mm (0.310 inch). The left and right heights are also preset to within ± 0.7 mm (0.030 inch) of the other.

The cutting unit is designed to withstand blade impacts without deformation of the chamber. If the blade strikes a solid object, inspect the blade for damage and the blade plane for accuracy.

Replace the blade if it hits a solid object, is out of balance, or is bent. Always use genuine Toro replacement blades to ensure safety and optimum performance.

1. Park the machine on a level surface, raise the cutting unit to the highest position, engage the parking brake, shut off the engine, and remove the key.

   Note: Block the cutting unit to prevent it from accidentally falling.

2. Grasp the end of the blade using a rag or thickly-padded glove.

3. Remove the blade bolt, anti-scalp cup, and blade from the spindle shaft (Figure 124).

   

   Figure 124

   1. Blade bolt
   2. Anti-scalp cup

4. Install the blade, anti-scalp cup, and blade bolt and tighten the blade bolt to 115 to 149 N∙m (85 to 110 ft-lb).

   Important: The curved part of the blade must be pointing toward the inside of the cutting unit to ensure proper cutting.

   Note: After striking a foreign object, torque all spindle-pulley nuts to 115 to 149 N∙m (85 to 110 ft-lb).

Both the cutting edges and the sail, which is the turned-up portion opposite of the cutting edge, contribute to a good quality of cut. The sail lifts the grass up straight, thereby producing an even cut. However, the sail gradually wears down during operation, lowering the quality of cut even though the cutting edges are sharp. The cutting edge of the blade must be sharp so that the grass is cut rather than torn. A dull cutting edge leaves the tips of the grass brown and shredded. Sharpen the cutting edges to correct this condition.

1. Park the machine on a level surface, raise the cutting units, engage the parking brake, put the traction pedal in NEUTRAL, put the PTO lever in the OFF position, shut off the engine, and remove the key.

2. Examine the cutting ends of the blade carefully, especially where the flat and curved parts of the blade meet (Figure 125).

   Note: Because sand and abrasive material can wear away the metal that connects the flat and curved parts of the blade, check the blade before using the machine. If you notice wear, (Figure 125), replace the blade.

   

   Figure 125

   1. Cutting edge
   2. Curved area
   3. Wear/slot forming
   4. Crack

3. Examine the cutting edges of all the blades and sharpen the cutting edges if they are dull or nicked (Figure 126).

   Note: Sharpen only the top of the cutting edge and maintain the original cutting angle to ensure sharpness (Figure 126). The blade remains balanced if the same amount of metal is removed from both cutting edges.

   

   Figure 126

   1. Sharpen at the original angle.

   Note: Remove the blades and sharpen them on a grinder. After sharpening the cutting edges, install the blade with the anti-scalp cup and blade bolt; refer to Removing and Installing the Cutting-Unit Blade(s).