5 Common Kubota M5-111 Problems and Solutions

The Kubota M5-111 comes with a 3.8-liter, 105.6 horsepower engine, making it a powerful utility tractor. However, users have complained of several issues when using this tractor model. The most common Kubota M5-111 problems are hard starts, sensor malfunctions, DEF running low, steering problems, and issues with the fuel tank.

When looking for an ideal tractor, you should weigh its pros against its cons to see how friendly it will be. Read on as we detail common issues you’ll face if you purchase a Kubota M5-111.

Kubota M5-111 DEF Problem

Diesel exhaust fluid (DEF) comprises deionized water and urea and helps reduce pollution. Kubota M5 111 DEF problems are mostly due to the anti-pollutant running low, which may slow down the engine.

You may also encounter DEF issues in winter due to the freezing point of the deionized water. Freezing will affect the engine’s performance, resulting in engine failure. It is advisable to address the problem promptly, lest it gets out of control.


You fix this problem by regularly checking the DEF tank’s level and refilling it if low. For winter conditions, the fluid should not be full to the brim. Water expands when cold and may damage the tank. If the DEF freezes, refrain from pouring water into the tank to melt it, as it may compound engine troubles.

When cold, park the tractor in warmer spots to prevent its fluid from freezing. Install a DEF system on the tractor to shield the DEF tank from low temperatures.

Kubota M5-111 Sensor Malfunctions

Kubota’s DEF system has sensors that alert you of any setbacks. The sensors may malfunction, meaning you won’t get notified if things are not well. Sensor malfunction is a severe issue as the engine may wear fast without you knowing.

How To Fix

If inspection points to a problem with the sensors, you need to replace them immediately. It is a costly but necessary process for your tractor’s well-being.

Problems With the Fuel Line

Fuel is a source of various Kubota M5-111 problems, like hard starts and sudden stalling. The main culprits behind the fuel line troubles are low fuel, poor quality fuel, blocked fuel lines, leaks, and a faulty fuel pump.

Hitches with the fuel line can be severe and, besides affecting engine performance, may result in poor fuel economy. Let us look at the answer to this problem.


Inspect the fuel system if you feel it is the root of your tractor’s snags. Start by confirming if you have enough fuel in the tank. Go for high-quality fuel when refilling. 

If you use the wrong fuel, flushing the line is the best solution. Flushing also helps to clear away debris that might cause clogging.

Talking about clogging, you may blame it on freezing conditions, which might solidify the fuel. The ‘iced’ fuel will flow differently than intended. No wonder your tractor fails to start in cold mornings. Add more fuel to melt the frozen barrier or avert the issue by parking in warm spots.

Starting Problems

You may notice some Kubota M5 111 problems when starting the tractor. The engine may start but turn over or fail to start. The following are possible causes of this complication.

  • Dead battery
  • Low fuel
  • Improper engine oil viscosity
  • Starter problems
  • Clogged filters

How To Fix

Probe the battery first, as it is the primary cause of starting problems. If dead, you can jumpstart it or get a new battery. The latter option is logical if you have used your current battery for almost ten years. Check the battery terminals and connections to see if they are okay. Clean the sulfate accumulation as they prevent current flow.

Regularly check and change the engine oil for the Kubota tractor to move smoothly. Clean clogged oil and air filters or replace them if they are badly worn out.

A faulty starter can make starting the tractor a headache. You should check its connections and fix them if they are broken. For a damaged starter, replacement is the best solution. You can try bypassing the starter, but it can be hectic in the long run.

Kubota M5-111 Steering Problems

One of the most frequent Kubota M5-111 problems lies with the steering unit. The tractor’s steering wheel is usually hard to turn or noisy as you turn. Kubota wheels might also fail to turn completely.

Steering issues are risky and can lead to accidents, especially when steering fails at high speeds or if there are obstacles on your path. The causes of this snag mainly emerge from the cylinder, though the entire suspension system can bring it up.


You troubleshoot the steering complications by inspecting the steering and suspension systems. As hinted earlier, the origin of the issue may be the steering cylinder: check it out to determine if it is functional. Tighten the bolts on the cylinder if they are loose to prevent the steering wheel from dropping.

The next area to check is the suspension, which may be the culprit if your tractor leans to one side. Low tire pressure and misalignment are probable causes of steering problems. Align the wheels and fix flat tires for a smooth drive when on the field.

Final Thoughts

This piece looks at the common Kubota M5-111 problems and their fixes. The DEF unit is significant in controlling emissions and needs you to check on the fluid levels at all times. Ensure the fluid is adequate but not brim-full, especially in winter.

Rarely will you experience problems with the hydraulic unit, but do not overlook it when maintaining the tractor. Also, pay attention to the fuel system, air conditioning unit, radiator, and wheels to get the best out of the M5-111.