skid steer hydraulic pump problems manufacturer

The hydraulic pumps on construction equipment are critical components of the machines and even though they are often designed to work under vigorous and intense conditions, no pump will last forever. Discovering a problematic pump can be complicated as the effects might seem to originate in other connected parts, and, if failures are gradual, the cascading effects of a pump failure can spread throughout a machine.

To help in your diagnosis — and with a small dash of preventive maintenance — we’ve put together this basic, short list of common pump problems and their causes.

Not every hydraulic pump on a machine is simple to inspect, but this Volvo main hydraulic pump on a EC220B-LC excavator sits behind a quick access door so an operator can check it often.

A failing hydraulic pump can be a long and subtle process, a sudden and catastrophic calamity, and all shades in-between, but often a perceptive operator will notice the signs of a pump failure in advance. It might take a few minutes of stopping and inspecting, but knowing what to watch for and taking the time to inspect your hydraulic pumps can often pay off in the long run and lead to fast and simple fixes, instead of prolonged and labor-intensive downtimes.

A hydraulic pump is often secured behind a door or guard or integrated deeply into the body of a machine, but taking the time to inspect the pump for the presence of oil (or oil and dirt clumping) can lead to the early discovery of problems. If the issue is simply a loose connection, a quick tightening can often stop a small issue from growing.

Since a hydraulic pump has both seals to prevent fluid from exiting the pump and also fluid from prematurely entering from one chamber to the next, failing seals can be both internal and external. Spotting an exterior leak is, of course, simpler, but being aware of where seals exist inside the pump can also help you diagnose a failing internal seal.

The most frequently noticed indication of a failing pump is often the start of a new sound coming from the hydraulic pump. An experienced operator will often immediately know and recognize a pump that is indicating issues through sounds, but for many it can be harder to pinpoint.

A problem with a pump can cause it to simply become louder in its operations, develop a whining sound, or even create a knocking sound. The sounds can indicate a number of problems, but often the cause is either cavitation or aeration in the pump.

Over long spans of work and under intense conditions, a hydraulic pump will often heat up, but excessive heating is often a sign of internal issues in the hydraulic pump. Checking a hydraulic pump for excess heat should always be done with safety in mind and with a secure machine and proper protective equipment. Periodically ensuring a hydraulic pump isn’t overheating allows an operator to discover if the pump is under undue strain and on a path to failure.

Overheating in a hydraulic pump can also cause fluid to thin, cause internal components to more rapidly degrade, and introduce dangerous working conditions to the machine. Overheating in a pump is both a sign of current trouble and a cause of other growing problems.

Unexpected and non-fluid movement of parts can be caused by issues with the hydraulic pump, but since the culprit can be a number of other parts in the system, diagnosing pump issues from these movements isn’t always simple. Still, if you do notice non-uniform movements in your machine, taking time to rule out the hydraulic pump is important.

A main hydraulic pump, like this one from a Komatsu PC400LC-6 excavator, comes with a working life and will need to be replaced or rebuilt at some time. This one is fresh from an H&R Recon and Rebuild shop and is headed to a customer.

Knowing some of the common causes of hydraulic pump failures is a proven way of proactively discovering developing issues and correcting them before they become disastrous to the pump and the machine.

The internals of a hydraulic pump are designed to work with fluid that meets exacting specifications. When hydraulic fluid is contaminated it can lead to issues developing in the pump, force the pump to work harder, and cause the pump to work erratically. One common culprit for contamination is water, and it can quickly lead to increased corrosion, changes in viscosity that lead to inefficiencies, and the inability to properly regulate heat in the pump.

Other debris, either introduced from outside or from the degradation of internal elements, can also lead to issues in the pump and signal failing seals or other parts.

A hydraulic pump is often containing a high level of pressure and as this pressure exerts force on seals in the pump, the seals can begin to leak or fail. Even minor leaks in seals can lead to loss of fluid and create issues in the system. Leaks can be both external and internal. For an internal leak, fluid will move from one part of the pump to another in unintended ways and force inefficiencies into the pump as it has to work harder to compensate.

While many hydraulic pumps are built to stand up to tough and continuous working conditions, every hydraulic pump is designed with an upper limit. Every time a hydraulic pump is subjected to overpressuring and overloading beyond what the manufacturer has specified, the pump is more prone to damage.

All hydraulic oil has a defined amount of air dissolved in it, but increases to this amount can lead to inefficiencies in the pump and force the pump to work harder or erratically. An increase in air can also happen inside the pump and create similar problems. Even though the pump and hydraulic system have mechanisms in place to regulate air in the system, if excess air is introduced the system should be returned to a balanced system before prolonged use of the pump.

The hydraulic system on a construction equipment machine is designed to work within defined parameters. Operating a machine with too little oil or too much oil for even the briefest amount of time can cause the pump to overwork, lead to increases in working temperatures, or create conditions for non-uniform movement. The exact type of oil used — matched to the machine and the working environment — can also impact how the hydraulic pump operates.

The operator’s guide of your machine will define the hydraulic oil change schedule and adhering to that schedule can extend the life of your hydraulic pump. When oil is changed, take time to examine the spent oil for signs of debris

Keeping a pump on a hard-working machine looking new every day is nearly impossible, but routinely peeling back dirt, grime, and oil can help catch issues early.

No one wants to take a machine out of work for cleaning, but keeping the machine clean and ensuring pumps are not covered in mud, dirt, or other debris can allow them to be inspected more easily and avoid contamination and overheating.

The hydraulic hoses connected to a hydraulic pump can wear out over time and ensuring they are well-maintained can help you avoid the introduction of debris and even catastrophic issues in the case of sudden failures.

If a hydraulic pump fails on your machine, taking time to ensure you properly diagnose why and how the failure occurred will help you avoid repeating the failure with your replacement pump. Even if the pump failed simply from prolonged use and age, taking time to confirm that can lead to insights about how to extend the life of the next pump.

A hydraulic pump on an excavator, wheel loader, dozer, or articulated truck can be an often ignored component of the machine — until it starts to act up and cause issues. If problems have brought a pump to the forefront of your mind, hopefully, this short guide has helped simplify your pump problem solving.

If you find yourself in need of a replacement hydraulic pump, our Parts Specialists are always here to help. As a supplier of new, used, and rebuilt hydraulic pumps and with our deep inventory of parts, our Parts Specialists can often find the perfect solution to get a customer back up and running quickly. Simplify your search and give them a call.

The look and design of a hydraulic pump is customized to fit the machine and the available space. This main hydraulic pump is freshly reconditioned from a Kobelco SK160LC-VI excavator.

Hydraulic pumps come in a wide range of shapes and sizes. This large Volvo main hydraulic pump requires assistive overhead cranes and forklifts to move around the warehouse.

Pumps are the heart of hydraulic systems, and when they quit working, your equipment is dead. That’s why it is so important for you to know the four key signs of an impending pump failure!

Right before a pump completely fails, operators usually notice a loss of power or change in how the machine behaves. For example, the arms on a skid steer loader might not have their normal lifting power or the arm on a compact excavator may behave erratically. The arms on an excavator or a skid steer may be moving much more slowly.

Another bad sign is a pump that suddenly starts making some new noises or exhibiting excessive vibration. That can point to quite a few different causes, from loose set screws to failed bearings.

Another bad sign for pumps is when they start running hotter than normal. That can point to quite a few things, such as contamination in the system or a dirty heat exchanger. It can also point to issues within the pump, too.

Leaks are another bad sign, and when ignored they can lead to a host of problems for your pump. A leak indicates that a seal is wearing out and needs to be replaced -- and this makes sense, because seals will eventually wear out.

If you ignore the leak, then dirt, grit, dust, grease, and moisture can make their way into the pump. This type of contamination will cause the pump components to wear out faster than they should, and lead to clogged filters.

If you see any of these symptoms, then you need to schedule some time to have your pump repaired. The solution might be as simple as replacing a seal or bearing, or it could be a more troubling issue like cavitation. Regardless of the

Your hydraulic pump is the heart of your machine, pumping fluid through your hydraulic system. Pump failures mean downtime and expensive repairs, but the sooner you recognize pump problems developing the easier it is to fix. In this Shop Talk blog post, we are going to discuss, we are going to discuss the most common signs and causes of hydraulic pump failure.

If you notice any of these symptoms, keep in mind that it doesn’t necessarily mean that the pump is going out -- but it means something in your hydraulic system is about to! Check out this video below for an example of what can happen to a Bobcat pump.

A bent or misaligned rod can cause problems, too. If you notice that your seals are repeatedly failing, this could be the cause. And keep in mind that a seal that leaks also allows contamination to get inside.

Sadly, no pump will last forever because they suffer wear and tear from regular use. Bearings and seals will eventually need to be replaced, and if those replacements are put off then your pump may suffer even worse damage. If you suspect your hydraulic pump needs a tune up, then don’t hesitate to see after it -- it will extend the life of your pump and increase your machine’s overall productivity.

is your partner in providing new or remanufactured final drive hydraulic motors from a single mini-excavator to a fleet of heavy equipment. Call today so we can find the right final drive or hydraulic component for you, or check out our online store to.

Many customers having problems with the lift and tilt hydraulics on their skid steer ask “Will a new hydraulic pump fix the problem I am having with my bucket not lifting or tilting?”

- Another hard to find problem happens sometimes to pumps that are directly mounted to the back of drive pump. The gear pumps often have ahole drilled through the mounting flange to allow the drive pump case to drain oil into the gear pump suction. Any air that leaks into the drive pumpcase can then be sucked into the gear pump. Check the drive pump control shaft seals for wetness. This indicates a leak. Also check the gear pump mounting, sometimes people forget to install a mounting o-ring. This can leak air in as well.

­- If not you will need to check and possibly readjust the relief valve setting. Please don’t do this without a gauge or you may end up blowing a hose or pump.

- If lift is stronger at high rpm this indicates internal leakage. The more speed you have the more oil flow you have, this additional flow at high rpm can make up for the internal leakage and mask the problem. You most likely have a bad pump, but before your spend the money on a replacement, let’s check a couple of last items that could also be theproblem.

­There you have it. 99% of the time these simple checks will correctly pinpoint the problem. However the only way to know for sure exactly what condition your pump is in is to hook a flow meter to the outlet and measure the flow under load. This will generally cost you about $100 in shop labor, so at this point you can decide if you want to spend money for a definite diagnosis or just go ahead and replace your pump. If you decide to replace the pump, please check out our pump installation precautions to avoid costly mistakes that others have made.

When a hydraulic system fails, finding the source of the problem can be a challenge. Though hydraulic systems primarily consist of a sump, motor, pump, valves, actuators and hydraulic fluid, any of these parts could be the source of failure. That"s not to mention the additional potential for failure through human error and faulty maintenance practices. If your system fails, you need to know why it fails, how to find the failure and how to keep it running smoothly in the future, all while keeping personnel safe.

It"s often easy to tell when a hydraulic system fails — symptoms can include high temperatures, low pressure readings and slow or erratic operation are glaring problems. But what are the most common causes of hydraulic systems failures? We can trace most hydraulic issues back to a few common causes, listed below.

Air and water contamination are the leading causes of hydraulic failure, accounting for 80 to 90% of hydraulic failures. Faulty pumps, system breaches or temperature issues often cause both types of contamination.

Air contamination is the entrance of air into a hydraulic system and consists of two types — aeration and cavitation. Both can cause severe damage to the hydraulic system over time by wearing down the pump and surrounding components, contaminating hydraulic fluids and even overheating the system. Although we are not pump manufacturers, we know it is essential to be aware of these types of contamination and how to identify their symptoms.

Cavitation:Hydraulic oil consists of about 9% dissolved air, which the pump can pull out and implode, causing pump problems and damage to the pump and to other components in a hydraulic system over time. You can identify this problem if your hydraulic pump is making a whining noise.

Aeration:Aeration occurs when air enters the pump cavity from an outside source. Usually, loose connections or leaks in the system cause this issue. Aeration also creates a sound when the pump is running, which sounds like knocking.

Water contamination is also a common problem in hydraulic systems, often caused by system leaks or condensation due to temperature changes. Water can degrade hydraulic components over time through oxidation and freeze damage. A milky appearance in hydraulic fluid can help you identify water contamination.

Fluid oxidization: Extreme heat can cause hydraulic fluid to oxidize and thicken. This fluid thickening can cause buildups in the system that restrict flow, but can also further reduce the ability of the system to dissipate heat.

Fluid thickening:Low temperatures increase the viscosity of hydraulic oil, making it harder for the oil to reach the pump. Putting systems under load before the oil reaches 70 degrees or more can damage the system through cavitation.

Fluid levels and quality can affect hydraulic system performance. Low fluid levels and inappropriate filtration can result in air contamination, while fluid contamination can cause temperature problems. Leaks can further exacerbate both issues.

Using the correct type of fluid is also essential, as certain hydraulic oils are compatible with specific applications. There are even oil options that offer higher resistance to temperature-related problems. Some oils even offer anti-wear and anti-foam additives to help prevent against wear and air contamination, respectively.

Human error is the base cause of many hydraulic system problems. Some of the most common errors that may result in your hydraulic pump not building pressure include the following.

Faulty installations: Improper installation of any component in a hydraulic system can result in severe errors. For example, the pump shaft may be rotating in the wrong direction, negatively affecting pressure buildup, or pipes may be incorrectly fitted, resulting in leaks.

Incompatible parts: An inexperienced installer may put mismatched components together, resulting in functional failures. For example, a pump may have a motor that runs beyond its maximum drive speed.

Improper maintenance or usage:Using systems outside their operational capabilities or failing to perform regular maintenance are some of the most common causes of hydraulic system damage, but are easy to rectify through updated maintenance policies and training.

The sources of system failures can be tricky to identify, but some hydraulic troubleshooting steps can help narrow down the options. So how do you troubleshoot a hydraulic system? Here are some of the fundamentals.

Check the pump: Take the pump assembly apart and assess all parts to ensure that they are functional and installed correctly. The most common problem areas include the pump shaft, coupling and filter.

Check the fluids:Check the level, color and viscosity of the hydraulic oil to ensure it meets specifications and has not become contaminated. Low hydraulic fluid symptoms include pressure or power loss. When in doubt, drain and replace the fluids.

Check the seals: Look for evidence of any fluid leakage around your hydraulic system"s seals, especially the shaft seal. Leakage can indicate worn-out or blown seals that can cause malfunctions with pumps, motors and control valves.

Check the filters: Ensure filters are clear of plugs and blockages. Common clogged hydraulic filter symptoms include sluggish operation and noisy operation.

Hydraulic system issues are inevitable at some point. However, simple steps can help you avoid these issues and increase the longevity of your hydraulic system. On top of effective troubleshooting, you can prevent hydraulic system failure by taking the following steps.

Follow specifications: We can trace the most common hydraulic system issues back to fundamental system problems like incompatible or improperly installed parts. For this reason, it"s essential to always double-check specifications to ensure your purchased parts can work together seamlessly.

On top of these steps, look into hydraulic system products that are specifically designed to help prevent failures. One such product is Bear-Loc® by York Precision. This innovative locking actuator is a safe, reliable feature for hydraulic components, automatically locking when sleeve pressure is relieved, preventing movement if a hydraulic system fails. This way, your can protect your personnel from injuries related to hydraulic failures. Even better, York Precision offers in-house design, engineering expertise and machining and manufacturing capabilities to produce a hydraulic locking device that meets your exact specifications.

Regularly review hydraulic system maintenance, always following manufacturer recommendations and industry best practices. Also, consider the storage condition, external influences, working pressure and usage frequency of your system to tailor your maintenance schedule and procedures.

Daily tasks:Take care of a few simple daily checks to avoid issues. For example, personnel should check the oil levels, hoses and connections and listen to the pump for abnormal sounds.

Be mindful of location:Do not stand at endpoints while working on hydraulic systems. This safety measure can help prevent loss of limb and life, as there is a lot of pressure built up in these areas that can release and result in life-threatening situations.

The best safety measures, however, are to perform excellent maintenance and use high-quality parts. If you"re looking for a quality hydraulic component manufacturer, York Precision Machining & Hydraulics can help.

Things like restrictions and blockages can impede the flow of fluid to your pump. which could contribute to poor fluid flow. Air leak in suction line. Air present in the pump at startup. Insufficient supply of oil in pump. Clogged or dirty fluid filters. Clogged inlet lines or hoses. Blocked reservoir breather vent. Low oil in the reservoir

Now that we’ve ensured that the directional control is not reversed, it’s time to check that the drive motor itself is turning in the right direction. Sometimes incorrect installation leads to mismatched pipe routings between control valves and motors, which can reverse the direction of flow. Check to see that the motor is turning the pump in the right direction and if not - look at your piping.

Check to ensure that your pump drive motor is turning over and is developing the required speed and torque. In some cases, misalignment can cause binding of the drive shaft, which can prevent the motor from turning. If this is the case, correct the misalignment and inspect the motor for damage. If required, overhaul or replace motor.

Check to ensure the pump to motor coupling is undamaged. A sheared pump coupling is an obvious cause of failure, however the location of some pumps within hydraulic systems makes this difficult to check so it may go overlooked

It is possible that the entire flow could be passing over the relief valve, preventing the pressure from developing. Check that the relief valve is adjusted properly for the pump specifications and the application.

Seized bearings, or pump shafts and other internal damage may prevent the pump from operating all together. If everything else checks out, uncouple the pump and motor and check to see that the pump shaft is able to turn. If not, overhaul or replace the pump.

If your pump is having problems developing sufficient power, following this checklist will help you to pinpoint the problem. In some cases you may find a simple solution is the answer. If your pump is exhibiting any other issues such as noise problems, heat problems or flow problems, you may need to do some more investigation to address the root cause of your pump problem. To help, we’ve created a downloadable troubleshooting guide containing more information about each of these issues. So that you can keep your system up and running and avoid unplanned downtime. Download it here.

Hydraulic pumps are used in almost every type of production system, from plastic mold injection machines to the common conveyor belt. With proper maintenance, most hydraulic pumps will operate smoothly for years, but even with proper maintenance, the pressure inside these devices will eventually cause failures that need to be addressed as soon as possible. The way to avoid total system failure is by monitoring your pumps and looking for the following warning signs.

Liquids should remain in the tubes that were designed for them. If you notice any liquids anywhere else inside the pump, you have a problem. A line may have a break, or a seal may be loose. No matter what the case, an interior leak means your pump has gone bad.

Have you discovered liquid on the outside of your pump? This means either an interior leak has worsened or there could be a leak on the HPU that the pump is mounted to. This leakage results in reduced pressure in the system and immediate action is required to repair and salvage the pump. Leaking reduces the pressure, which increases the temperature of the system. This affects the viscosity of the oil, reducing the pressure in the system.

Increased fluid temperatures can be the result of the system’s inability to dissipate heat. In most systems, heat within the fluid dissipates through the fluid in the reservoir and a heat exchanger. Heat can cause the fluid to thin, which prevents proper lubrication and may cause pump leaks, reducing pump efficiency and system performance.

Hydraulic fluid that has a milky appearance is a clear indication of water contamination. One source is condensation buildup on the walls of the fluid reservoir as a result of temperature changes from warm days to cool nights. Water contamination can also corrode the pump and other critical components, which can shorten component life. Periodic fluid changes and draining of the water from the reservoir ensure water removal from the system.

If your seals continuously leak and fail, your pump may be operating with a bent or misaligned rod. Depending on the extent of the damage, a skilled machine shop may be able to repair your existing equipment, allowing you to get the most out of your equipment and minimizing costs.

System moving slow? If performance decreases, this could be a sign that your hydraulic pump is starting to go bad or your system is designed incorrectly. This lack of efficiency indicates a lack of flow.

You never want to let your system run if your pump is suffering from any of these problems listed above because it means your system is on the verge of experiencing pump failure. These symptoms are an indicator that something could be seriously wrong and could result in some expensive damage to your hydraulic system. The hydraulic experts at Pneumatic And Hydraulic Company can help in identifying the warning signs and replacing your pump before the damage becomes too costly.

Whether it"s your construction vehicle or another piece of heavy machinery, the failure of a hydraulic pump can mean the failure of a project. However, before a hydraulic pump fails, it will often give a lot of warning signs first. Don"t ignore these signs of a failing hydraulic pump.

Hydraulic pumps make noise as they operate. You will grow accustomed to whatever noise you hear, which can help when the noises start to change. If you hear unusual noises, you may have a problem. At no time should your hydraulic system create banging or rattling noises.

A major cause of noise is aeration, which is what happens air becomes trapped within the system. Noises can also occur because the pump isn"t getting enough fluid. When there"s a lack of fluid, corrosion can take place which will contaminate the little fluid still in the system.

As that fluid circulates it can cause damage to every part of a hydraulic system. If you"re hearing odd noises from your hydraulic pump, then cease operating your heavy equipment or vehicle. You need to have the pump looked at to determine if you should repair or replace it.

Any leaking of hydraulic fluids should give you some concern. In larger hydraulic equipment, leaking is sometimes considered inevitable. However, when heavy equipment and vehicles show signs of leaking, you should immediately do what you can to mitigate the issue.

A leak that occurs inside or around the pump should prompt you to seek a repair. Equally, if you see signs of leaking outside the vehicle, then you can assume an interior leak has taken a turn for the worse. With a leak, the hydraulic system cannot maintain pressure, which can lead to issues with performance or outright system failure.

Sometimes, the leak doesn"t begin with the pump itself, but rather with a loose seal or a break in a line. Even when this is the case, the leak can lead to poor pump performance. Starting the investigation from the pump can often help to spot an issue with some other hydraulic component.

If your hydraulic system overheats, there"s a good chance a buildup of dirt and debris is causing the issue. Your hydraulic pump will have a hard time dissipating heat if the filters become clogged. The inability to release heat will cause temperatures to rise even higher.

As the heat increases, so does the temperature of the fluid. Hot fluid can weaken seals and degrade a lot faster than it should. Both those outcomes can mean further trouble for your hydraulic pump.

A bad hydraulic pump will lead to poor or sluggish performance. All the aforementioned issues can lead to a hydraulic pump that isn"t performing as it should. Nevertheless, even if you don"t experience any other issues, the drop in performance is a key sign you need to have your hydraulic pump repaired or replaced.

If your equipment depends on a functioning hydraulic system, you must stay diligent about keeping that system healthy. Monitor your hydraulic system and pay attention to any signs that something isn"t working as it should. Routine maintenance of your hydraulic system will help to keep its performance intact while also helping you find potential issues before they become problems.

Often, protecting the viability of your hydraulic pump only requires that you keep up with changing the fluid and replacing smaller components when necessary. You can often save a hydraulic pump with an issue by having it repaired or rebuilt by a professional service.

AtCarolina Hose & Hydraulics, we specialize in high-quality hydraulic components for heavy equipment and vehicles. Contact us for any of your hydraulic pump concerns immediately.

Precision Hydraulic Inc. is you’re knowledgeable and dependable Supplier for all major hydraulic equipment manufacturers and industries. If it’s hydraulic “Precision can Repair and Test It”. Below a list of just some of the brands we repair.

See our extensive hydraulic repair and reconditioning experience serving the markets listed below. Contact us. Learn more about Precision’s hydraulic pump, hydraulic motor, hydraulic valve, and hydraulic cylinder repair and service.

See our extensive hydraulic repair and reconditioning experience serving the markets listed below. Contact us. Learn more about Precision’s hydraulic pump, hydraulic motor, hydraulic valve, and hydraulic cylinder repair and service.

Road Construction: Asphalt Pavers, Vibe Rollers, Material Transfer Vehicles, Cold Planers, Sweepers, Concrete Concrete Mixers, Concrete Pumping Trucks, Concrete Placers/Spreaders, Batch Plants, Concrete Pavers, Loaders, Excavators, Skid Steer Loaders, Horizontal Directional Drills, Trenchers, Cranes, Soil Stabilizers

The true depth of our knowledge lies within the diagnosis and repair of hydraulic pumps and other hydraulic products. Whether we have your unit in stock or not, the repair is always an option. In fact, it may be your best option for obsolete and hard to find hydraulic pumps, motors, valves, and servos.

The heart of your hydraulic system - It is crucial that your hydraulic pump provide you with consistent and reliable performance. If you’ve got a leaky, noisy, or unsatisfactory performing pump, allow us to evaluate it for free and overhaul it with quality OEM or aftermarket parts to get your system. We handle piston, gear and radial piston pumps that come from a variety of mobile and industrial applications ranging from excavators and skid steers to garbage and dump truck PTO pumps.

Valves are another critical component of your hydraulic system, they control all of the flow, sequencing and movement of your other hydraulic components. When you have a valve that is not functioning as expected, it can really throw off or even stop production. NGCH offers repair for directional hand controlled valves from log splitters, wood chippers, processors, crane controls, material handling, farm tractors, and mobile equipment.

We at North Georgia Cylinder & Hydraulic, Inc. have more than just know how for hydraulic repairs. We also have experience in machine shop services such as manual and CNC milling as well as manual and CNC lathe. This allows us to do more extensive in-house cylinder/pump repairs versus outsourcing our metalworking needs. Furthermore, if you need a replacement pin, manifold, shaft or a prototype part, allow us the opportunity to see how we can help! We work with all sorts of materials from mild, alloy and stainless steel, to aluminum, brass, bronze and plastics such as UHMW, PTFE, Delrin and PVC.

The second leading cause of hydraulic pump failure, behind contamination, is cavitation. Cavitation is a condition that can also potentially damage or compromise your hydraulic system. For this reason, understanding cavitation, its symptoms, and methods of prevention are critical to the efficiency and overall health of not just your hydraulic pump, but your hydraulic system as a whole.

The product of excessive vacuum conditions created at the hydraulic pump’s inlet (supply side), cavitation is the formation, and collapse of vapors within a hydraulic pump. High vacuum creates vapor bubbles within the oil, which are carried to the discharge (pressure) side. These bubbles then collapse, thus cavitation.

This type of hydraulic pump failure is caused by poor plumbing, flow restrictions, or high oil viscosity; however, the leading cause of cavitation is poor plumbing. Poor plumbing is the result of incorrectly sized hose or fittings and or an indirect (not straight or vertical) path from the pump to the reservoir. Flow restrictions, for example, include buildup in the strainer or the use of an incorrect length of hose or a valve that is not fully open. Lastly, high oil viscosity—or oil that is too viscous—will not flow easily to the pump. Oil viscosity must be appropriate for the climate and application in which the hydraulic pump is being used.

The greatest damage caused by cavitation results from the excessive heat generated as the vapor bubbles collapse under the pressure at the pump outlet or discharge side. On the discharge side, these vapor bubbles collapse as the pressure causes the gases to return to a liquid state. The collapses of these bubbles result in violent implosions, drawing surrounding material, or debris, into the collapse. The temperature at the point of implosion can exceed 5,000° F. Keep in mind that in order for these implosions to happen, there must be high vacuum at the inlet and high pressure at the outlet.

Cavitation is usually recognized by sound. The pump will either produce a “whining” sound (more mild conditions) or a “rattling” sound (from intense implosions) that can sound like marbles in a can. If you’re hearing either of these sounds, you first need to determine the source. Just because you hear one of these two sounds doesn’t guarantee that your hydraulic pump is the culprit.

To isolate the pump from the power take-off (PTO) to confirm the source, remove the bolts that connect the two components and detach the pump from the PTO. Next, run the PTO with no pump and see if the sound is still present. If not, it is safe to assume your hydraulic pump is the problem.

Another sign you may be experiencing cavitation is physical evidence. As part of your general maintenance, you should be inspecting and replacing the hydraulic oil filter"s elements at regular intervals based on the duty cycle of the application and how often it is used. If at any time during the inspection and replacement of these elements you find metallic debris, it could be a sign that you’re experiencing cavitation in the pump.

The easiest way to determine the health of your complete hydraulic circuit is to check the filter. Every system should have a hydraulic oil filter somewhere in-line. Return line filters should be plumbed in the, you guessed it, return line from the actuator back to tank—as close to the tank as possible. As mentioned earlier, this filter will have elements that should be replaced at regular intervals. If you find metallic debris, your pump could be experiencing cavitation. You’ll then need to flush the entire system and remove the pump for inspection.

Conversely, if you’ve already determined the pump to be damaged, you should remove the filter element, cut it open, and inspect it. If you find a lot of metal, you’ll need to flush the entire system and keep an eye on the other components that may be compromised as a result.

Once cavitation has been detected within the hydraulic pump, you’ll need to determine the exact cause of cavitation. If you don’t, cavitation can result in pump failure and compromise additional components—potentially costing you your system.

Since the pump is fed via gravity and atmospheric pressure, the path between the reservoir and the pump should be as vertical and straight as possible. This means that the pump should be located as close to the reservoir as is practical with no 90-degree fittings or unnecessary bends in the supply hose. Whenever possible, be sure to locate the reservoir above the pump and have the largest supply ports in the reservoir as well. And don"t forget, ensure the reservoir has a proper breather cap or is pressurized (3–5 PSI), either with an air system or pressure breather cap.

Be sure the supply line shut-off valve (if equipped) is fully open with no restrictions. This should be a “full-flow” ball valve with the same inside diameter (i.d.) as the supply hose. If feasible, locate a vacuum gauge that can be T’d into the supply line and plumb it at the pump inlet port. Activate the PTO and operate a hydraulic function while monitoring the gauge. If it reads >5 in. Hg, shut it off, and resume your inspection.

A hose with an inner bladder vulcanized to a heavy spiral is designed to withstand vacuum conditions as opposed to outward pressure. The layline will also denote the size of the hose (i.d.). You can use Muncie Power’s PPC-1 hydraulic hose calculator to determine the optimal diameter for your particular application based on operating flows.

Another consideration, in regards to the inlet plumbing, is laminar flow. To reduce noise and turbulence at the pump inlet, the length of the supply hose should be at least 10 times its diameter. This means that any type of shut-off valve or strainer at the reservoir should be at least 10 diameters from the pump inlet. A flared, flange-style fitting at the pump inlet can also reduce pump noise by at least 50 percent compared to a SAE, JIC, or NPT fitting.

Selecting the proper viscosity of hydraulic fluid for your climate and application is also critical. Oil that is too viscous will not flow as easily to the pump. Consult your local hydraulic oil supplier for help selecting the optimal fluid viscosity.

By maintaining a regular maintenance schedule, remaining vigilant for any signs or symptoms, and taking preventative measures, the good news is that you should be able to prevent cavitation and experience efficient operation for the duration of your pump’s lifespan.

Poor plumbing is the leading cause of cavitation and can be prevented by selecting a properly sized hose, choosing the appropriate fittings, ensuring the most direct, straight routing from the pump to the reservoir, etc.

We are independently certified as an ISO 9001:2001 organization. This means that every employee follows a structured and measurable set of policies and procedures to provide consistent, high-quality products and service. Customers all over the world rely on us to be their one-stop shop for all of their hydraulic and hydrostatic needs. They trust us to only use OEM parts and to provide our signature White Box Service. We specialize in handling all types of hydraulic units, for all kinds of machinery and equipment, including:

4. If you have power going back to your solenoids on your valve but the auxiliary hydraulics still won"t work, check the coils for resistance to see if they are within spec. They should have 3 to 5 ohms resistance. If they do not fall within this spec then it is faulty and need replacing.

One of the common causes of problems in mechanized systems is degraded hose fittings. Once we have inspected your agricultural machines and established this to be the root of the problem, we will ensure that the replaced hose fittings are in excellent condition. This helps to improve the longevity of the machine and deliver better performance.

We will discuss with you the specific needs of your hydraulic cylinders, allowing us to design the cylinder in such a way that they are tailored to your needs. If you have an existing cylinder in place, our team of experts will work on repairing it so that it helps you to meet your goals and objectives.

Over the years that we have provided agricultural machinery repair services, we have encountered customers with a wide array of needs. Today, we have all the machinery required to handle almost every type of hydraulic-related job. All you need to do is to contact us and explain what is on your mind, and we will devise a way to make it happen.

Aftermarket A20.5L36836 hydraulic gear pump for Bobcat applications, 1.220 CID with counter-clockwise (left) rotation. Direct fit for the following equipment: