14 Reasons Why Your Ariens Riding Mower Won’t Move Forward Or Reverse

When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

If your Ariens riding mower won’t move forward or reverse, it might be due to a blocked fuel filter, missing idler arm spring, a transmission failure, or a broken drive belt.

Continue reading to learn more about the causes and solutions for mobility issues.

But before we jump right into the possible solutions…

Some of the reasons why your Ariens riding mower won’t move forward or reverse include:

  • Worn, loose or broken drive belt
  • Missing idler arm spring
  • Drive release handle not in operating position
  • Hot hydraulic fluid
  • Blocked fuel filter

1.  Worn, Loose or Broken Drive Belt

Your Ariens riding mower won’t move forward or reverse if the drive belt is worn or broken. 

If you notice that it is falling off, you may need to tighten its grip on the pulley.

Fix: Replace damaged or worn-out drive belt. Make sure the belt is securely around the pulleys.

2. Bypass Control Lever Not In “Engaged” Position

If the bypass control lever isn’t in the engaged position, the Ariens riding mower may fail to move, affecting the operation and functionality of the mower.

Fix: Ensure that the bypass control lever is in the “engaged” position (pulled up and pushed in). 

You can contact your local authorized servicing dealer for evaluation and repair if the problem persists.

3. Blocked Fuel Filter

This is one of the reasons why your riding mower may fail to move forward or reverse. 

A clogged fuel filter can prevent gas from flowing to the engine in a proper supply, causing the riding mower not to move.

Fix: Replace the blocked fuel filter with a new one. 

4. Drive Release Handle Not in Operating Position

Ariens hydrostatic mowing machines are equipped with a drive release to enable them to roll freely.

This feature is helpful when your riding mower has stopped working and you need to push it onto a trailer. For you to be able to move your riding mower forward, the drive release handle needs to be in an operating position.

The drive release can be in the form of a knob, lever and pull/push button. You need to check your owner’s manual for the handle type that you have on your mowing machine and where to locate it.

Fix: Place the drive release lever in the operating position. 

5. Missing Key in Axle

This problem may occur if you recently changed your riding mower’s tire. It may also be that you missed a small key that fell out of the axle. 

For the wheel to move, you must install the missing key or else the mowing machine won’t move.

Fix: Replace the key in the axle.

6. Defective Tensioner Pulley

Some tensioner pulleys are made of hard plastic and they also have a bearing in the center. The pulley can break or its bearing can fail, causing the mower to move in the forward or backward position.

Fix: Inspect the pulley and replace it if it is in bad condition. Make sure that you keep the tensioner arm greased so that it will have some movement and also prevent it from seizing up. 

7. Low Hydraulic Fluid Level in a Ariens Riding Mower

If you run the transmission with low or old hydraulic oil, it may cause your riding mower to develop mobility issues.

Fix: To keep the transmission system of your Ariens riding mower running at an optimal level, it is advisable to ensure consistent hydraulic oil change at intervals based on the recommendations of Ariens.

You also need to change the hydraulic oil and filters at the recommended intervals.

If you notice that the hydraulic oil is low, you need to add more hydro oil till the level of the fluid gets to the full level when the hydraulic oil is cool.

8. Air in the Hydraulic System

It is necessary to bleed the air out of the system after changing the hydraulic fluid. Air in the system may make the mower not move.

Fix: Follow Ariens’s procedures for changing the hydraulic fluid and bleeding air from the system in the owner’s manual.

9. Hot Hydraulic Fluid

When you operate your riding mowing machine with low fluid or bad hydraulic fluid, the oil will not be able to lubricate the hydraulic system with efficiency. Furthermore, it can cause increased friction and overheating of the hydraulic fluid.

When the hydraulic fluid gets hot, it can cause further damage to the mowing machine.

Fix: It is advisable to take your mowing machine to the local repair dealership if the hydraulic pump is leaking or if the mower operates well when it is cold, but stops operating when it gets hot.

10. Free Wheeling Valve Not Engaged

If your riding mower does not forward or reverse, the free wheeling valve may be disengaged.

The freewheeling valve is usually located low on the rear side of your mowing machine. If it is not engaged, the mower may fail to move in forward or reverse position.

Fix: It is advisable to contact a technician to solve the problem.

11. Missing Idler Arm Spring

The idler arm spring can put tension on the mower deck drive belt of a riding lawn mower. It clips onto the bracket and idler arm that is in the mower frame or deck. 

If the idler arm spring is missing, the mower may fail to move forward or reverse.

Fix: It is advisable to replace the missing or broken spring. 

12. Transmission Failure

Transmission problems can result in an inability to shift gears which will prevent your Ariens lawn mower from moving in a forward or reverse position.

Leaks in transmission lines or fluid reservoirs can cause shifting problems. This can cascade to engine parts like pistons and sticking valves

Fix: It is best to contact an expert to troubleshoot the problem for you.

13. Broken Piece in the Linkage

Your Ariens riding mower may not move in a forward or reverse position if there is a broken piece in the linkage where there is a spring holding pressure on the arm.

Fix: You can try to move the lever back and forth to see if there is something stopping it from moving front or back. 

If it is still in bad condition, it is best to seek the help of an expert to help you fix the issue.

14. Ariens Mowing Machine Stuck in Mud

A lack of friction can cause your Ariens riding lawn mower to get stuck in the mud. 

In this case, the mower wheels will find it difficult to create friction with the wet surface for it to move in the forward or reverse position.

Fix: To regain friction, you need to place material in a sheet form under the wheels. Here are suggestions  to follow when finding a friction substitute for your Ariens riding lawn mower:

Sheet Material or Panel

  • Hauling trailer decking sheets.
  • Chipboard sheets or plywood.
  • Plastic or latticework panels or composite trellis.

Other Material

  • Sand (for icy applications)
  • Lengths of chain
  • Gravel
  • Large wood chips

Ariens Riding Mower Transmission Problems

If the transmission of your Ariens riding lawn mower is faulty, it may arise as a result of:

  • Bad or defective transmission pulley
  • Hydraulic controls leak by the lever.
  • Bad drive belt
  • Constant paddle slipping or stuck in the middle.
  • Bad hydraulic fluid.
  • Defective pressure switch

Troubleshooting Tips

  • Replace the defective parts or inspect the inline filters.
  • Connect and disconnect the control valves.
  • Replace the bad drive belt. 
  • Put the mower lever in bypass mode and try to restart it
  • Drain and replace the old hydraulic oil.
  • Install a new pressure switch.

Ariens Riding Mower Transmission Maintenance Tips

Here are some of the maintenance tips for your Ariens riding mower transmission:

  • Change the transmission oil every four hundred hours of operating your mowing machine.
  • Drain out the transmission fluid at the start of the winter and replace it with new hydraulic fluid in the following spring.
  • You can also seek the help of a professional to help you run periodic diagnostics on your Ariens mowing machine.


If you notice that your Ariens riding mower won’t go forward or reverse, it is important to figure out the causes.

Some of the possible causes include a missing key in the axle, a missing idler arm spring,a bad tensioner pulley, and a worn drive belt.

Follow the troubleshooting tips to fix the mobility problem. If your Ariens riding mower does not work well after trying these troubleshooting tips, contact a technician to fix the issue.