Bad Boy Mower Troubleshooting

Troubleshooting your Bad Boy mower can help resolve a number of issues without the need to spend a lot of money on it. Most problems with these mowers are simple DIYs which can clear easily when the right troubleshooting procedure is followed. While some procedures may not work for all models, other steps are similar. In this guide, we give step-by-step instructions on how to resolve some common Bad Boy mowers challenges.

Bad Boy Mower Transaxle Problems

The hydrostatic system on MZ models is a sealed lifetime transaxle system, so no maintenance is required.

To move the mower while the engine is not running, follow the instructions below:

  • Find two levers located under the rear of the mower. These bypass levers serve as a neutral for moving the mower while the engine is not running.
  • Pull the levers out and lock them into place to activate the bypass.

To change your Hydraulic oil and filter:

  1. Place an oil drain pan beneath the oil filter. Remove the oil filter from the oil reservoir to drain the oil.
  2. After the oil has drained from the reservoir, install a new oil filter. Tighten 3/4 turn past gasket contact.
  3. Fill the reservoir with new motor oil through the fill cap. The oil level should be filled until the level reaches the bottom of the upper fitting. Do not overfill. If there is an air bubble in the tube, add oil until the level reaches the fitting and the air bubble is no longer visible.
  4. Drain the old oil filter of all free-flowing oil before disposal.
  5. Proceed to purge procedure.

To purge air from the system:

  1. Lift the rear tires of the mower off the ground and chock your front tires so they do not move.
  2. With the bypass valve open (To open bypass valve, loosen 1/2 to 1 full turn) and the engine running, slowly move the directional drive arms in the forward and reverse directions (5-6 times), as air is purged from the unit, the oil level will drop.
  3. With the bypass valve closed and the engine running, slowly move the directional drive arms in the forward and reverse directions (5-6 times). Turn off the engine. Check the oil level, and add oil as required after stopping the engine.
  4. You may have to repeat steps 1 through 3 until all the air is completely purged from the system. When the tire moves forward and reverses at normal speed purging is complete.

To adjust the tracking on the mower, lengthen, or shorten the pushrods. Lengthening the pushrod will increase the speed of the pump. Shortening the pushrod will decrease the speed of the pump. On-the-fly adjustments can be made by turning the adjustment knob of either steering arm until the desired effect is achieved.

Bad Boy Mower Deck Problems

  1. Uneven cutting pattern and decline in cut quality

If your mower is not cutting or there is a decline in the cut quality, it could point to a problem with the deck or components within the deck. To troubleshoot, try the following instructions:

  • Check blade sharpness (replace blades or sharpen at least once per year or when needed).
  • Make sure blades are tightened properly.
  • Check spring and belt tension.
  • Check the underside of the deck to ensure the mower is free of grass build-up and debris.
  • Make sure your machine is at full throttle.
  • Vary your mowing pattern each time you cut your grass.

How to level the deck on My Bad Boy Zero Turn Mower

  • Start on a flat, level surface and set the air pressure in the front tires to 12 psi and 8 psi in the rear. Measure the deck at all four corners. The deck should be level from left to right but 1/4-inches lower in the front than in the rear. To make adjustments, adjust the deck hangers in their slots.
  • Using a pair of 2 by 4’s approximately 3 ft long, stand the boards on the edge and slide them under the deck from front to back.
  • Lower the deck down onto the 2 by 4’s using either the deck lift pedal or the electric actuator. The deck should now be approximately 3.5 inches off the ground. To achieve the proper 1/4 inches pitch down in the front you may need to use some 1/4 inches spacers under the rear of the deck.
  • Using a pair of 3/4 inch wrenches, loosen all deck hanger bolts on the top of the deck. Do not loosen the upper bolts that attach the deck hangers to the actuator lift bars. Your mower may also be equipped with a deck lift assist. This will cause the actuator bars to lift on their own once all the deck hangers have been loosened.
  • The deck is now loose from the frame and movement of the lift pedal or electric actuator should only move the hanger bolts up and down in the deck slots. At this point, a different deck height may be chosen on the cutting height dial. Choosing a lower number will raise the decks cutting height. Choosing a higher number will decrease the decks overall cutting height.
  • After setting the deck dial to the desired position and securing the lift pedal rearwards until it stops, tighten all deck hanger bolts in their slots starting from the rear of the deck then moving to the front. Lift the deck to the highest position. Measure all four corners of the deck again to ensure that no further adjustments are required.
  • Recheck the belt tension before mowing.

Check this too: Toro Lawn Mower Troubleshooting

Bad Boy Mower Electrical Problems

Problems with the electrical system can prevent your mower from starting. Follow these instructions to troubleshoot problems in the electrical system:

  • Check the condition of the wiring harness ground cable. The ground is located inside the right side fuel tank on most models. Make sure the ground is connected, clean, and tight. On some Bad Boy mower models, this wire may be connected to the negative side of the battery.
  • Check the condition and connection of the relays located under the seat. Make sure that they are clean and connected. Ensure that wire terminals have not pushed out of the relay block.
  • In most models, the red wire coming out of the engine is the charging wire from the alternator. Check for 13.6-14.2 volts DC at this wire with the engine at full throttle.
  • Ensure all fuses are clean and well connected.
  • Replace blown out fuses.
  • If you are having issues starting your mower ensure the signal wire is connected to your starter solenoid.

Bad Boy Mower Steering Problems

There are several causes for steering problems on a mower, with the most common cause is hitting a foreign object while mowing. This can jar the wheels and negatively affect the steering system. Other problems may simply occur from wear and tear of the components with time.

To prevent steering problems follow these instructions:

  • Drive your lawn carefully. Avoid making sudden sharp turns and hitting foreign objects.
  • When not using the mower, store it away from the weather elements in a secure garage or shed.

If you hit a foreign object and a gear slipped, try these instructions to fix the problem:

  1. Loosen the bolts holding the top and bottom parts of the steering gearbox together.
  2. Turn the steering wheel completely to the left to snap the gears back into position.
  3. Realign the steering wheel and tighten the bolts back into position afterward.

To fix a popped ball joint:

  1. Loosen the nut on the assembly holding the ball joint.
  2. Pop it back into position.
  3. Tighten the nut again to repair.

Bad Boy Mower Safety Switches

Your Bad Boy mower is equipped with a safety interlock system. This system is designed to prevent serious injuries or death to the operator and other people or property damage. The system consists of:

  • An operator switch in the seat
  • The parking brake
  • Drive lever neutral position
  • Blade engagement switch
  • Ignition switch

Bad Boy Mower Won’t Start

Your Bad Boy mower may fail to start because of a number of reasons.  It may be due to a bad or drained battery, bad connections, and a clogged air filter among other possible causes. If you are experiencing this problem, try the following tips to troubleshoot:

  • Check battery charge and connection.
  • Check all visible wires and connections.
  • Check your fuel. Make sure your fuel is fresh (less than 30 days old) and that there is no water in the tank.
  • Make sure the air filter is clean. A dirty or clogged air filter will make it more difficult for the engine to draw air.
  • Make sure your spark plug is in good condition and the spark plug wire is attached. If in doubt, replace it.
  • Check all in-line fuses.
  • Review starting procedures in your operator’s manual.

Where are the Fuses on a Bad Boy Mower?

MZ series models are equipped with three protective fuses: a 25-amp main fuse, a 10-amp clutch fuse and a 15-amp linear actuator fuse. The main fuse is located on the left side of the unit; by the starter solenoid. The clutch fuse is located just underneath the control panel along with the linear actuator fuse.

On most larger commercial engines (27 hp and up), the 25 amp main fuse is located about 3 inches from the starter on the engine.

How Do You Reset the Hour Meter on a Bad Boy Mower?

The electronic hour meter displays hour increments up to 9,999.9 total hours, resettable timers, oil change reminders, air filter cleaning reminder, and RPM gauge. Press the button to cycle between functions. To reset a timer, depress and hold the button for 2 seconds.

How Fast Does a Bad Boy Mower Go?

Bad Boy mowers speeds can range between 4-12 mph. It may vary depending on the model. For example, the ZT elite residential zero-turn mower has a ground speed (forward) of up to 7 mph.

How Do You Adjust the Deck on a Bad Boy Mower?

If your machine is equipped with an actuator motor:

  • Raise the deck using the raise/lower switch.
  • When the deck is raised, set the desired height with the deck height control dial, then lower the deck with the raise/lower switch.

If your machine is equipped with a foot pedal:

  • Press the foot pedal to raise the deck.
  • Select your desired deck height with the deck height dial, then slowly release the foot pedal.

Why is My Bad Boy Mower Draining its Battery?

There are several possible causes for a draining mower battery:

  • Mower components left “on”

Some mower components are powered by the battery once the engine is off. If these components are left on when you switch the mower’s ignition off, the battery continues to supply them with power. Leaving the key in the “on” position is a mistake that can drain the battery in a short time.

  • Corrosion around the battery posts

The presence of corrosion indicates the battery has a loose connection at the posts, or that gases inside the battery are leaking out and reacting with the metal terminals. A loose connection makes a battery work harder, thereby draining it of power more quickly. To troubleshoot, clean the corrosion, tighten battery connections, and check if there are cracks on the battery case.

  • Dying battery

As the battery reaches the end of its serviceable life, it fails to hold a charge for very long. If your battery fails to hold a charge for a week or two, it may be nearing the end of its useful life and will need to be replaced.

  • A faulty or damaged battery recharging system

An alternator and a voltage regulator are part of the electrical system that recharges a mower battery. If these parts fail, replacing them may restore power to the battery next time you run the mower.

How Do You Adjust the Belt Tension on a Bad Boy Mower?

If your Bad Boy mower belt has slipped or performs poorly, you can adjust it using a spring tension adjustment on the pump belt that attaches directly to the pump spring. It is a black, all-thread bolt that can be adjusted by tightening the 1/2-inch nuts on the part.

To adjust the deck belt, loosen the nut on the deck idler spring and slide the spring forward or backward to add or remove tension accordingly. You can use a 0.030 Feeler Gauge to determine the correct belt tension.

How Do You Replace the Pulley on a Bad Boy Mower?

To remove and replace the deck belt on a bad mower, follow these steps:

  • Remove the ignition fob.
  • Raise the deck to its highest position.
  • When lifting up on the belt, rotate the pulley until the belt is free of the pulley. Be careful when performing this step as fingers can easily get caught between the belt and the pulley.
  • Remove both pulley covers and route the belt by following the belt route decal. Rolling the belt onto the left spindle pulley is the easiest way of reinstalling the belt.
  • Verify that the belt is routed properly.