Kubota Hydraulics Troubleshooting: Here's What You Should Know

From an owner or operator's perspective, it pays to know how to troubleshoot the most common problems found in Kubota vehicles. This will save you from an unnecessary trip to the mechanic or the service center of your heavy machinery. Likewise, being able to solve petty problems right out can reduce the downtime of your equipment, which can negatively affect your overall productivity.

In this article, we will show you the most common problems owners and operators encounter with their Kubota loaders and tractors.

Hydraulic Cylinder Drift

Hydraulic cylinder drift is a problem commonly experienced by owners of Kubota loaders. The symptom is that the loader's hydraulic cylinders do not stay in place or return to their original position when pressure is released from the system. This can cause a loss of control, which could lead to serious accidents and even death if left unchecked.

The most common cause of hydraulic cylinder drift is air in the system. This can happen when there is a leak or when new components are installed. The solution is to bleed the system and make sure all connections are tight, secure, and free from leaks. In addition, be sure to use only OEM parts or equivalent quality replacements when making repairs and replacements.

Other causes of hydraulic cylinder drift include failing seals, worn-out spools, or even a bent or broken piston rod. Check all cylinders for wear and tear and replace any faulty parts with OEM replacements or equivalents that are specifically designed for the Kubota loader model.

It is also important to check lubrication levels in the hydraulic system and replenish the fluids as needed. If the problem persists, it is possible that the loader's valves are not working properly and may need to be replaced.

Particulate Contamination

Particulate contamination in a hydraulic system is often caused by the accumulation of foreign materials such as dirt, dust, and debris. This material can clog filters, obstruct valves, and reduce the efficiency of the system. The most common symptom of this type of contamination is an increase in pressure or heat within the system. Other signs may include sluggish operation, leaks, and noisy or erratic performance.

To troubleshoot the symptoms of particulate contamination in a Kubota's hydraulic system, it is important to identify the underlying cause. Poor maintenance can lead to increased wear on internal components, leading to debris accumulation over time. Additionally, if the machine is often used in dusty or dirty environments, the air filter may become clogged and lead to increased particulate levels.

Once the cause has been identified, it is important to begin addressing the problem at its source. If poor maintenance or a clogged air filter is causing contamination, these issues should be addressed before attempting any cleaning or repairs. Once the underlying issues have been addressed, the hydraulic system should be inspected for any visible signs of contamination, such as dirt or dust in the oil.

Inspecting, cleaning, and replacing internal components is also necessary to prevent further contamination as well as flushing its fluids and replacing it with a fresh batch. Commonly worn elements like pumps, hoses, and seals are particularly prone to failure due to particulate buildup. These parts should be inspected regularly or replaced if necessary. Additionally, filters and strainers should be inspected to ensure they are not clogged with debris.

Water Contamination

Water contamination in the hydraulic system of a Kubota loader can cause various symptoms such as weak power transmission, abnormal lubricating oil temperature, increased noise levels, and struggle in its operation. The most common cause is moisture getting into cracks or partial openings in the hydraulic system components as well as wet contaminants entering the reservoir, and improper filtration.

If you suspect such an issue, drain the hydraulic fluid of your vehicle and replenish it with a fresh batch. Make sure to use hydraulic oil that meets the manufacturer's specifications and install a high-quality filter on the return line.

Regularly inspect components such as hoses and seals for any signs of leakage or wear. Replace them as soon as possible if necessary. Additionally, ensure the system is filled with clean oil and that all dirt, debris, or contaminants have been removed.

To reduce the chances of water contamination, use a high-grade air breather filter on the tank to prevent condensation from entering the system. Additionally, fit an oil cooler in order to keep temperatures low and reduce vapor pressure within the system.

When it comes to parts, keep an eye on the hydraulic pump as this is one of the most common causes of failure in Kubota loaders. Check for signs of leakage or wear and replace if necessary. Additionally, ensure that all filters are clean and properly fitted to prevent dirt from entering the system. The oil pressure relief valve should also be inspected regularly to ensure it is functioning properly.

Finally, make sure that all connections are tight and secure to prevent any air from entering the system. Make sure there are no leakages or loose connections as this can cause water contamination as well. With regular maintenance and periodic checks, these issues can be avoided and your Kubota loader can continue to perform well.

Air Bubbles in the System

Air bubbles in the hydraulic system of a Kubota loader can cause several symptoms, including decreased power, slow response time when operating controls, and unintended movement. To troubleshoot these problems correctly, it is important to start with the most common causes.

The first step is to check for air leaks in the hoses or fittings of the hydraulic system. If any of these components are loose or have any visible damage, they will need to be replaced before proceeding with further troubleshooting. Additionally, it is important to check for blocked or faulty valves and clogged filters. Any defective part should be replaced as soon as possible.

If no air leaks are found, then the next step is to bleed the air from the system. This can be done by disconnecting the return hose and attaching a hand pump to it while running the system. Cycle the pump several times until all of the air has been purged and only hydraulic fluid is seen in the hose.

Common components that tend to fail and need replacement are cylinders, hoses, and pumps. These parts can become worn out over time and should be inspected regularly to ensure they are functioning correctly. If the problem persists after replacing these components, then it could be a sign that other more complex repairs may be necessary.

Clogged Filter

A clogged filter in the hydraulic system of a Kubota loader can cause a wide range of problems, such as sudden changes in speed, sputtering, and even complete engine shutdown. It is important to identify the causes and take steps to prevent further damage. One common cause of filter blockage is old oil or debris that has accumulated over time. This can cause clogging in the filter, resulting in reduced flow and eventually leading to engine problems.

Another common cause of filter blockage is an oversized or worn-out filter element. If the size of the element does not match the system, it may become clogged more quickly than normal, causing a decrease in performance and an increase in wear and tear on the hydraulic system. Additionally, using a worn or dirty filter element can put excessive pressure on the system, leading to further blockage.

The most common solution for this problem is to replace the filter element with a new one. In some cases, it may also be necessary to replace other parts such as o-rings, seals, and gaskets. Additionally, replacing the hydraulic oil can help to dislodge any debris that may be present in the system. If all of these steps do not restore normal operation, it may be necessary to replace additional parts such as the pump or motor.

Proper maintenance of the filter is essential for avoiding filter blockage. Regular cleaning and oil changes should be performed to ensure the hydraulic system is running optimally. It is also important to make sure the correct size filter element is installed for optimal performance. If any parts are worn or damaged, they should be replaced immediately to prevent further damage.

Overheating

Overheating in the hydraulic system of a Kubota loader can be caused by numerous issues. Faulty cooling system components are often responsible for overheating problems in hydraulic systems.

The radiator, water pump, fans, thermostat, hoses, and clamps, as well as the coolant, should all be inspected for signs of damage. A defective radiator can lead to the insufficient circulation of coolant within the system, resulting in overheating and eventual engine failure. The water pump may also fail due to wear or obstruction. Clogged cooling system components can impede the flow of coolant, reducing its efficiency. Additionally, a loose or broken fan belt can lead to overheating, as it prevents the engine from cooling properly.

Another common issue that causes the hydraulic system to overheat is insufficient oil pressure. Low oil levels in the system reduce the amount of fluid available for lubricating and cooling moving parts. This can result in excessive friction and heat build-up, leading to overheated components. Low levels of oil pressure may also be caused by worn seals or a dirty filter that needs to be replaced.

Aging engine parts are another common cause of overheating in a Kubota loader's hydraulic system. Cracks, wear and tear on the piston, cylinder head or valves can cause oil leakage. This leads to an insufficient amount of fuel and lubrication for the engine, resulting in overheating. Additionally, any broken components should be replaced as soon as possible to prevent further damage from occurring.

Finally, a faulty control valve can also be responsible for overheating problems in hydraulic systems. When the valve is open, too much pressure can be created in the system, leading to overheating. To prevent this from happening, it is important to check and replace any faulty valves.

Conclusion

Should any of these basic troubleshooting tips fail to solve whatever issue you are facing with your Kubota, it's already possible that you may be encountering a more complex problem in the background. In this case, you should bring your machine for professional servicing as soon as possible.