9 Kubota L3901 Problems and Quick Fixes

Kubota L3901 Problems

Kubota is arguably one of the most established brands, particularly renowned for their excellent line of farm tractors.

The L3901 model will meet most of your farm needs with its state-of-the-art features and high-performance capability.

However, despite its great value, beware of several malfunctions bound to occur with your machine.

This post addresses several Kubota L3901 problems while providing their troubleshooting options. Read more to learn more;

9 Common Kubota L3901 Problems

  1. Engine Doesn’t Cranks
  2. Engine Starts and Stalls
  3. Steering Issues
  4. Trouble with Regeneration
  5. Engine Overheats
  6. PTO Failure
  7. Electrical Issues
  8. Clutch Problems
  9. Area too Small for the Operator

Problem 1. Kubota L3901 Engine Doesn’t Cranks

You must’ve encountered this issue if you’ve used your tractor for a long time. Usually, the engine may take longer or fail to crank completely.

Typically, this problem occurs due to issues with the tractor’s battery. Similarly, your tractor may encounter this issue if the cables or terminals have eroded.

Also, if excess dirt and debris collect inside the battery’s housing, it may prevent your mower’s engine from cranking.

The Fix

Luckily, you can easily diagnose and fix this issue. First, you’ll want to ensure that the battery has enough charge.

Next, inspect all cables and correct any loose connections since they tend to slacken over time. Thirdly, ensure that the housing is clean.

Check for corrosion and excessive dirt and clean using a wire brush. If your battery runs out of charge after all these attempts, it may be defective. In this case, you’ll want to replace it with a new battery.

Lastly, use an Ohm meter to test the safety switches of your mower to ensure they dissipate the correct voltage. If none of the fix work for your model, contact a reliable service provider immediately.

Problem 2. Kubota L3901 Engine Starts and Stalls

This issue is inherent to most tractors such as Kubota L2501. Typically, your machine will start and then stop mid-operation suddenly. This can be cumbersome, especially when performing a mowing or farming project.

This issue is usually due to a defective fuel injection pump or a faulty fuel line. Similarly, dirty or clogged air filters may cause your mower’s engine to start and stop suddenly.

Also, your tractor may stop mid-operation if it’s starved of fuel due to faulty fuel filter components. Usually, your tractor only operates efficiently if the engine has a consistent fuel supply.

The Fix

Inspect the fuel pumps and ensure they’re operating optimally. For example, a faulty fuel pump limits fuel flow to the engine, impacting the tractor’s performance.

So, to resolve the issue, replace pump with a new one. Next, clean the fuel filters to eliminate any dirt, debris, or sludge. Such debris clogs the filter, disrupting the fuel supply.

Also, inspect the entire fuel system to ensure fuel goes through without hindrance. If obstacles, including dirt, are present, clean up the fuel lines using high-pressure air.

Besides fuel supply, the engine may start and stall if there’s insufficient airflow. So, you’ll want to inspect the air filters and clear any debris that could result in clogging.

Problem 3. Kubota L3901 Steering Issues

Although less common, you may encounter steering issues with your tractor, especially after extended usage.

While this might result from a range of issues, it’s more likely to occur if air gets into the hydraulic system that operates the steering pump.

Also, cylinder malfunctions may cause the steering to misbehave. When the issue arises, you’ll experience resistance when steering your mower freely.

In addition, the steering might be loose or unresponsive, making it difficult to control the tractor.

Similarly, steering issues may result in your tractor pulling in one direction when you’re operating it.

This occurs when one steering wheel stiffens more than the other, especially after applying full throttle to the arms.

The Fix

First, inspect the transmission fluid and top it up to the recommended level. Next, If there’s air in the transmission line, bleed it out.

Also, check the oil and fuel levels and top up as required. Alternatively, inspect the tires and ensure the pressure’s equal.

Unequal tire pressure will make the tractor’s body dip, pulling it over to one side. If this doesn’t resolve the problem, check and replace any broken steering cylinders.

Problem 4. Kubota L3901 Trouble with Regeneration

The regeneration process is vital to ensure the smooth operation of your Kubota tractor. Typically, a major issue with the Kubota L3901 is the light continues to indicate even after the regeneration stops.

This becomes a nuisance, especially since this model undergoes regeneration every half an hour.

Unfortunately, in some cases, the regen light doesn’t cease flashing even after raising the RPM. Also, some parts are likely to malfunction if the tractor goes into park regeneration.

Frequent regeneration results in more fuel consumption and causes overheating of nearby components, which could degrade your machine.

Additionally, the heat produced may burn the grass or hay below, destroying the surrounding.

The Fix

The light should stop indicating after the regeneration process completes. So, if you’re experiencing any trouble, allow the tractor’s regen process to last for at least 15 minutes.

Then, the light should stop flashing automatically. If the flashing error persists, a quick fix is to trick the tractor by setting your engine speed to a higher RPM and waiting until the lights stop indicating.

Problem 5. Kubota L3901 Engine Overheats

The engine overheating is a widespread concern among Kubota users. However, it’s common to encounter this issue among other brands.

Probable causes that may trigger overheating in your Kubota engine include a clogged or dirty radiator. Also, your engine could overheat if there’s insufficient fluid in the cooling system.

When dust and debris are present in the radiator, it disrupts airflow, limiting the tractor’s ability to purge out the hot air.

As a result, the engine becomes hotter progressively. Over time, the heat attains unbearable levels, which might result in your tractor’s engine shutting down abruptly.

The Fix

Clean the radiator fins by blowing compressed air to eliminate debris. Additionally, inspect the engine’s coolant and top it up to the required level.

Similarly, if the current coolant is stale or old, flush the entire system and replace it with a new coolant. Typically, stale cooling fluid will have some debris floating around.

Problem 6. Kubota L3901 PTO Failure

Power Take Off (PTO) failure may occur due to several reasons. A major cause is the bush hog shuts down when the PTO isn’t connected to power.

When it occurs, the PTO shaft turns without engaging the PTO itself. Additionally, if the shaft won’t turn after you’ve engaged PTO, it’s more likely that it has malfunctioned.

Similarly, if the tractor won’t move after turning the PTO on, your Kubota Power Take-Off is faulty.

The Fix

When you encounter any PTO issues, it’s best to take the recommended action to fix them immediately.

Inspect the clutch component for any damages and replace it with a new one if you notice any defects. If the clutch operates optimally, Inspect the PTO control valve, which may cause issues due to floating points.

Next, perform the pressure test to confirm that the PTO control valves are in perfect working condition. When you spot weak seals on the control valve, replace it with a new one.

Also, if the throttle valve seal is defective, you’ll notice an RPM shift. In this case, you’ll need to replace the valve.

Problem 7. Kubota L3901 Electrical Issues

Electrical issues may affect different aspects of your tractor. Your tractor may fail to start due to a faulty or dirty spark plug.

The spark plug creates an electrical current to ignite the fuel. So, it should be in the proper condition to initiate combustion.

Also, your mower may fail to start if the battery is defective or lacks enough charge. This occurs if the tractor lies unused for a long time, especially during the winter.

Similarly, defective cells may render your battery unable to store charge.

The Fix

First, try recharging the battery to see if it resolves the issue. However, if the cells have gone bad, you’ll want to replace the battery.

Also, check for corrosion and loose connections around the battery’s terminal. If the spark plug has gone bad, replace it. Fortunately, spark plugs are affordable, thus easily replaced.

Problem 8. Kubota L3901 Clutch Problems

The clutches on most Kubota lawn mowers have been troubling their owners for a long time. However, it persists more in this model.

This issue might result for several reasons, including a misaligned release impact. Similarly, you could encounter clutch issues if the hurl arm bushing is worn.

Also, a worn-out pilot component could cause the clutch to malfunction. Regardless of the cause, a malfunctioning clutch component makes it hard to operate the tractor.

The Fix

If you’re experiencing trouble with your Kubota L3901 clutch, take the tractor to a reliable service company. They’ll figure out the problem and return the tractor to its optimal performance.

Problem 9. Kubota L3901 Area too Small for the Operator

Tractors require a driver to operate them. Unfortunately, operating the Kubota L3901 becomes increasingly challenging due to the small area designated for the driver.

This makes it uncomfortable for drivers who are more than six feet tall.

The Fix

Unfortunately, there isn’t much you can do to resolve the issue. We can only trust Kubota to hear the plea and correct the issue on future models.

Kubota L3901 Review – Is the L3901 Model Worth It?

The L3901 model from Kubota is an excellent option if you are looking for a reliable tractor. However, like any other equipment, it comes with its setbacks.

As a result, you’ll want to weigh all your options before settling for them. While these are valid complaints, they shouldn’t deter you from making your purchase.

The L3901 has a lot to offer, both in terms of features and performance. The Kubota L3901 is incredibly powerful and efficient.

It has a 4-cylinder diesel engine that provides 39 horsepower, making it adept at heavy lifting.

The hydrostatic transmission provides seamless shifting and no-hassle operation, making it easy to use even for inexperienced operators.


How any hours will the kubota diesel last?

Kubota tractors, which offer a more-than-average lifespan, deliver a service span of up to 5500 hours. However, with adequate care and maintenance, expect your tractor’s diesel engine to last up to 10000 hours. Luckily, Kubota tractors are heavy-duty and require minimal maintenance needs.

What does the em light mean on a kubota tractor?

The EM code, which is almost invisible within the engine symbol, indicates that your Kubota tractor is overheating. It could also mean that the temperature in the engine is lower than the overheating verge but could impact the operating efficiency of nearby components.

How to clear codes on kubota tractor l3901

  • Long-press both yellow buttons and turn on the key
  • Use the right button to go to service mode B
  • Next, long-press the right button to initiate Service mode B
  • Wait until the display reads clear, or push
  • Afterward, long-press the right button to clear codes
  • When the machine turns off after the occasional beeping, turn off the key and wait for 10 seconds
  • Return to normal operation

How much does a kubota l3901 cost?

The L3901 tractor from Kubota includes the 2WD and 4WD tractor models. 4WD models cost about $23500, while the 2WD tractor model costs about $21500. Additionally, the cab model costs up to $26500 while non-cab model prices may cost up to $24 500.


The Kubota L3901 has been the go-to tractor for most people’s farm needs. It’s a powerful yet flexible model that is easy to use.

Additionally, it incorporates many features that make it worth spending your hard-earned money on.

However, you’ll have to contend with various Kubota L3901 problems that may limit the machine’s functionality.