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Bad Boy Zero Turn Won’t Move Forward or Reverse (7 Reasons)

When moving the drive arms on your zero-turn to move forward and reverse, the wheels move very slowly or won’t even move at all. This could be a simple repair or a more significant transmission problem.

A Bad Boy zero-turn mower won’t move forward or reverse when the transmission is bypassed; the pump drive belt is loose or worn; the tensioner pulley or spring is worn; the hydraulic fluid is hot or old, or there is air in the hydraulic system.

Be careful working with the transmission system. Wait for the system to cool before performing any repairs or an oil change. Follow all safety precautions listed in the operator’s manual.

Bad Boy zero turn won't move forward or reverse transmission

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Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.

7 Reasons a Bad Boy Mower Won’t Move Forward or Reverse

Drive Release Levers Not in the Operating Position

You will find two neutral bypass levers at the rear of your mower. These levers are used to bypass the transmission to be able to push the mower and free-roll it without the engine on.

These bypass levers are used when the mower quits in the middle of the yard and you need to push it back to the garage or onto a trailer.

The Bad Boy mower will not move using the drive arms if the bypass levers are not in the “operating” position to power the wheels.

The transmission bypass levers must be pushed in towards the mower for the “operating” position so you are able to move the mower forward and reverse using the driving arms.

Pump Drive Belt is Worn, Loose, or Broken

A worn drive belt can affect the movement of your zero-turn. Check the drive belt to make sure it hasn’t fallen off and is positioned correctly on the pulleys.

If the belt shows any signs of wearing, the belt should be replaced. If the belt appears in good condition, check the tensioner pulley and spring.

The belt tension should be at 60-65 lbs. Make an adjustment to the belt tension, if needed, by adjusting the jam nuts on the tensioner.

Tensioner Pulley is Bad

The bearing in the tensioner pulley or the pulley itself can break. Many pump tensioner pulleys are made of hard plastic which can break or wear over time.

Replace a pulley that is worn or has a bad bearing. Keep the tensioner arm greased so it does not seize.

Missing or Worn Idler Arm Spring

The idler spring places tension on the pump drive belt. Replace the spring if it is broken or has fallen out of your Bad Boy. Adjust the spring tension if needed.

Low Hydraulic Fluid Level

Consistent hydraulic fluid changes must be completed to keep your transmission system running at its best. Running the transmission with old or low hydraulic fluid can cause your mower not to move or seem very weak while running.

Always check the hydraulic fluid level before using the mower while the oil is cool. Wipe around the caps before removing them to check the fluid.

Dirt is often a factor in a failed hydraulic system so you want to take all precautions to not contaminate the system.

When your hydraulic oil is low, add more hydraulic fluid until the fluid level reaches the FULL COLD line on the hydraulic fluid reservoirs. You will find two reservoirs located under the seat.

The hydraulic fluid in a zero-turn must be changed at regular intervals to keep the hydraulic system operating at its best.

Use Bad Boy hydrostatic oil or 20W-50 oil. Change the oil and filters after the initial 50 hours. The following oil and filter changes must be done at 250-hour intervals.

It’s also a good idea to check for hydraulic fluid leaks when you find your hydraulic oil level is low. Contact your Bad Boy zero-turn mower dealership for assistance with hydraulic fluid leaks.

Hot Hydraulic Fluid

When you operate a zero turn with bad hydraulic fluid or low fluid, the oil is not able to efficiently lubricate the hydraulic system causing increased friction and overheating of the hydraulic fluid.

Hot hydraulic fluid in your mower can also indicate more extensive damage.

I highly recommend taking your lawn mower to your local dealership if you experience leaking from the hydraulic pump or your mower runs fine when it is cold, but stops running when it gets hot.

Air in the Hydraulic System

Air trapped in the hydraulic system can cause your zero turn to move slowly or not move at all. After changing the hydraulic fluid, you must bleed the air out of the system.

Air can be removed from the hydraulic system by raising the rear drive tires off the ground. If you are unable to do this, find a large open area free of obstructions to perform the procedures on the ground.

Open the bypass valves, remove the parking brake if it is on, and start the engine. Move the drive levers slowly forward and then reverse about 6 times.

Close the bypass valves. With the throttle at high, move the drive levers forward and reverse about 6 times. Repeat this process until you don’t hear excessive noise and the tires move at normal speeds.

Once the air has been removed, shut off the engine and engage the parking brake. Check the expansion tanks to ensure the oil is at the FULL COLD line. If not, add oil until it is up to this line.

Still Experiencing Problems with Your Bad Boy Zero Turn Mower?

Own a lawn mower long enough, you’ll start running into problems with it starting, not continuing to run, smoking, leaking gas, giving a bad cut, vibrating, or another issue.

To help you save time and money, I have put together a guide to help you troubleshoot the next problem that develops on your mower.

You can find this guide at Common Bad Boy Lawn Mower Problems & Solutions.

If you are unsure how to perform diagnostics and repairs on your lawn mower safely, it’s best to have a professional complete the repairs.

This will help you avoid personal injury or additional damage to the mower. Your local Bad Boy lawn mower dealership or lawn mower repair shop will be able to help you solve your problem.