Skip to Content

How to fix a self-propelled lawnmower? How to diagnose with fixes

Self-propelled lawnmowers are a class higher than push mowers. They are perfect for yards up to ¾ acres. Unlike a push mower, they push themselves forward. They reduce fatigue caused by push mowers, particularly when you have a challenging yard. Some models offer both front and rear wheel drives and require only steering by the user. Such mowers have a gear transmission system and related components. If you face any issue or the mower does not move, the same transmission system must be checked. In this article, we will take you through the steps of how to fix a self-propelled lawnmower. Mostly, the error lies with the geared tires or transmission. Continue reading for a detailed insight on individual components.

How to fix a self-propelled lawnmower. How to diagnose with fixes:

To fix the self-propelled lawnmower, you will have to check individual components to find the error source. First, check the gears in the drive wheels. If they look bad, you have to replace them. Check the drive belt. If it is not tight or slipping, you need to adjust it. If it looks bad, replace it. Check the transmission box if the gears are connected, and the drive wheels move freely. Check the drive cable. If broken, fix it.

(CC BY 2.0) by sridgway

Self-propelled lawnmowers significantly reduce the human energy needed. Although the gear locking and drive belt mechanisms are quite sturdy, they may also face issues from time to time. Usually, a stuck self-propelled lawnmower will have problems related to its driving tires. They may not be working as they are supposed to. Occasionally, one may notice a fault in the drive belts responsible for the efficient transmission system. Fixing them may seem technical, but it is relatively simple. The problem can often be solved at home with some simple fixes, adjustments, or replacing some parts.

General Guide:

There are a few things you have to be careful about. You should precisely know what the error is and which part the error links to. When you have found that out, follow the following steps in order. Keep an eye on the user manual for information regarding various parts.

● Step 1: Gather the following tools

As all mechanics say, if you have the right tools and knowledge, consider the job half done. So, leave the technical solutions of problems to use, and you gather the following tools to make the task easier:

  • Pliers
  • Adjustable wrench
  • Screwdriver
  • Wooden block
  • Safety gloves

● Step 2: Park on a leveled surface and remove the spark plug

Park the lawnmower on a well-leveled, even surface before starting with diagnosing the problem. Disconnect the spark plug cable to ensure that the engine can not unintentionally start. If you have an electric lawnmower, disconnect the mains cable. In the case of a cordless electric lawnmower, remove the batteries. Also, apply the parking brakes so that the mower doesn’t move forward. Turn the ignition off and let the mower cool down before you start. Use a well-aerated and lighted space to focus better.

● Step 3: Check the drive wheels

The first step in fixing the self-propelled lawnmower is to check the condition of the drive wheels. But before that, you have to find out the drive wheels as they may be front or rear-driven, or even both. A clue to indicating them is that they will have the transmission box placed near them. One of the most common issues with such a mower is due to these drive wheels. Choose the wheel from one side. Remove it by unscrewing the nut at its center. You may use a socket wrench or pliers.

Hold it in your hand at some angle and check the gears on its inside. They are most likely to be eaten out if the lawnmower does not move. You cannot repair these flat gears, so it is better to replace them. Buy a matching tire depending on your mower brand and model. Screw it back so that it locks in the driving gears of the transmission. While you are at it, rotate the driving gears from the transmission system that connects with the tire. They should move freely, otherwise grease them. If the problem persists, you will have to check the drive belt. Then, repeat the process for the other drive wheel. The tire will no longer slip.

● Step 4: Check the drive belt

Check the drive belt of your mower. Check if it is slipping, the belt condition, and whether it is wound over the pulleys correctly. Lower the mower deck to the lowest stage possible. Turn the log lever present on one side of the steering wheel towards you to disengage the blades. Next, raise the mower on some platforms and examine from below.

Now, examine that the belt should be passing over the pulleys. There should be no sags, and the belt should be perfectly tight. If it is not, you need to adjust it. Locate the drive cable that originates from the drive control panel and comes down to connect with the transmission panel. There will be a metal bracket here that holds the connection between the belt and cable. Unbolt the bracket, pull it away from the belt so that it gets stretched. Now, tighten it at this spot. Check the belt’s stretch over the pulleys again. Turn the log ever to engage the blades. Put the mower deck back in its place.

● Step 5: Check the transmission box

The transmission box is a metal compartment that lies on top of the drive wheels. It contains the components that deal with driving the wheels. The drive belt, gear mechanism, and cable drive all connect here. The engine piston drives the transmission box through the drive belt. The gears convert the high RPM and low torque from the engine into a low RPM and high torque that propels the mower. The box itself is quite complex, and there are only a few things that you can check yourself.

Check that the belt drive is connected correctly and moves freely. Check whether the gears that connect the drive wheels move freely. If the gears connected with the belt are worn-out, then the error lies there. Check their condition by removing the box cover with a screwdriver. Check the drive cable’s connection too. If the error lies in the transmission box, you can locate it at most. It is quite complex, so better to get it repaired by an expert.

In any case, you would have solved the most major problems by now. Reconnect the spark plug cables, turn the ignition on. Start the mower and let it run for a while to lubricate all the parts.

Precautionary Measures:

Some things that you have to check before working on your lanwmower:

  1. Safety gloves: Use safety gloves when you work with sharp or hot lawnmower parts. You also protect your hands from grease and oil spills.
  2. Use quality parts: Try to use quality parts. This can mean good OEM parts or genuine parts that the company recommends.
  3. Disconnect the battery: Disconnect the battery before working on your lawnmower. It is easy to create a short circuit that can harm your battery and other electrical parts.

Related Questions

1. Are self-propelled lawnmowers better than push mowers?

The answer depends on you, your yard size, and your needs. Self-propelled lawn mowers are generally useful in smaller yard sizes, while push mowers do not have a specialized operation area. Self-propelled lawnmowers use more fuel, but they are easy to use, require zero effort, and are fast in operation. However, at the same time, they have expensive parts, are more complex, and have greater initial cost than push mowers. So, you have to choose while keeping your budget, needs, and ease in mind.

2. Can you push a self-propelled lawnmower?

Yes, you can also push a self-propelled lawnmower, but it will not make much sense. They are built to generate the push themselves. If you do push them, do not worry; it will not affect the transmission system. It is made strong and flexible due to the rough environment lawnmowers work in. However, pushing such a mower can be a very difficult task as they are generally quite heavy compared to simple mowers. The drive handle is also mainly built to guide the mower and not to bear the push force. So, although you can push them, it is better to avoid it.

3. Which is better, rear or front propelled lawnmowers?

Both of these types have their advantages. Front-wheel drive mowers are good for level terrains. The drive wheels are in front, making it easy to tip up the mower or turn the direction while mowing your grass. On the other hand, rear-wheel-drive mowers are more powerful, providing more traction at the mower’s center. This is suitable for hilly terrains. So, whether your yard is flat or has slopes, choose the type of mower that better suits your needs.

Final Remarks:

Self-propelled lawnmowers are one special type of mowers that pull or push themselves, or both if you have a four-wheel-drive system. They only require two things from you: guidance while mowing and proper care and maintenance. If your lawnmower loses its power or the tires slip or does not move, you have to check many parts to pinpoint the error. Check the drive wheels, drive cables, and transmission system, which is the most common cause of the trouble. In this article, we have explained step-by-step the details to fix your self-propelled lawnmower at home. This particular type of lawnmower is a bit complex having that well-intricate design. So, in case your problem does not solve, take it to an expert on the machine.