what size hydraulic pump for log splitter price

If you plan to replace the hydraulic pump in your log splitter or build your log splitter, you should know the size of the hydraulic pump that fits your log splitter. Log splitters are designed to split logs efficiently.

The machine uses a hydraulic system to power the splitting wedge to split logs efficiently. The hydraulic pump is an integral component of gas and electric splitters to provide the necessary power to do the job properly.

A log splitter is a powerful machine that splits logs of various sizes using hydraulic pressure. All log splitters – whether electric, gas, or manual – use hydraulics to feed the splitting wedge to cut the logs to just about any size you prefer.

The hydraulics system found in a log splitter consists of an engine, a hydraulic cylinder, a valve, an oil pump to create oil pressure, and a tank to hold and feed oil through the system.

Since the log splitter pump is one of the most important components of the machine, choosing the right kind of hydraulic pump for your log splitting machine becomes crucial when you need to replace the pump or plan to build your own log splitter.

Hydraulic pumps work according to the theory of hydraulics. The Principle of hydraulics or Pascal’s law governs how hydraulics work. Pascal’s law states that when you apply pressure to a specific point of a closed or confined fluid, the pressure will transmit to all other fluid points without any losses.

The hydraulic pump converts mechanical energy into hydraulic energy by using flowing water. The hydraulic pump uses flowing water to create a hydraulic system.

Even though the system is quite complicated, the operation is simple. Hydraulics provide force in a specific area. This force is what we call pressure which helps the log splitter perform its job effectively.

Log splitter pumps are two-stage hydraulic pumps. The entire splitting system is dependent on the pump. The pump consists of two pumping sections as well as an internal pressure sensing valve. One section of the pump helps generate the maximum flow rate at a lower pressure, and it is used to draw the piston back for the system to reset after splitting the log.

It takes very little force to draw the piston back into the cylinder after splitting the log. But, it should happen quickly. That is why you need the highest possible flow rate at low pressure.

When pushing the piston into the log, you need the highest possible pressure to generate maximum splitting force to split the logs efficiently. The flow rate is not a big issue here. Hence, the pump will switch to a high-pressure and low-volume stage to split the log.

When the size of the pump increases, it requires more fluid. But when there is more fluid in the cylinder of the pump, the speed & force of the pump decrease. That is why you need to choose the right size pump for your log splitter.

You can split logs more efficiently when opting for the correct size hydraulic pump for your log splitter. There are different sizes of hydraulic pumps in the market today. You should do your homework properly and opt for the right size pump for your log splitter.

The latest hydraulic pumps available in the market are based on GPM (Gallons per minute). The higher the GPM, the smaller the cylinder. The splitting force of the pump depends on the cylinder.

The pump that your log splitter needs will be dependent on the engine size of the machine. For example, a 5.5-6 hp engine can handle an 11 GPM 2-stage hydraulic pump, while an 8 hp or bigger engine can handle a 16 GPM 2-stage pump.

The engine of a log splitter works on hydraulics. While the pump will create the driving force, the hydraulic cylinder will work in unison with the valves, influencing splitting power and speed. If your log splitter has a 6-7 Horsepower engine, you should opt for a two-stage hydraulic pump (about 3000 PSI) with 11 GPM.

To get more speed, the pump either needs more flow (GPM) or a smaller cylinder. Smaller cylinders don’t require more power but will produce less force. More flow comes from a larger hydraulic pump. You will get the same force with a larger pump but supply more horsepower to the new hydraulic pump.

Are you planning to replace the hydraulic pump in your log splitter or build your own log splitter? If so, you should understand the basics of how a hydraulic pump works and what size pump to choose for your log splitter. To achieve automation, efficiency, and effectiveness, all log splitters rely on hydraulics.

Therefore, you should not worry too much as the size of the pump is only one aspect to look at. But the right decision about the size of the hydraulic pump is always useful in usage.

This 2-Stage pump fits a wide variety of log splitters and outdoor power equipment and works in both horizontal and vertical orientations. The included inlet nipple requires a 1" inner diameter suction hose.

Rated for up to 3,000 PSI at 3,600 RPM, this pump can power log splitters from 5 to 35 tons, depending on the inner diameter of the hydraulic cylinder. It features a fast cycle time by moving quickly when unloaded. It automatically shifts to low-flow/high-pressure mode at 500 PSI.

Be sure to use AW-32 10-Weight (ISO 32) or AW-46 20-Weight (ISO 46) light hydraulic fluid or Dexron III automatic transmission fluid. This pump is not designed for use with “universal” or "tractor" transmission oil, such as "303". The use of incorrect fluid may damage the pump and void the warranty.

Make sure the hydraulic fluid reservoir is not below the pump to ensure a sufficient flow of fluid to the pump. Suction-side filtration should be no finer than 150 microns. The use of a 10-25 micron filter on the suction side of the pump is too restrictive and will cause failure.

We recommend using an L-style jaw coupling to connect the pump to an engine. Couplings and mounting brackets are available. You should use at least a 5hp 163cc engine to maintain 3,600 RPM under load.

Log splitters are designed with a simple process in mind: to split logs efficiently. To do so, almost all use a hydraulic system to pressurize the driving force of the splitting wedge. When you purchase a log splitter, you don’t have to worry much about the individual parts other than for basic maintenance needs and cleaning purposes.

But if you are interested in building your own log splitter, which is a very realistic option due to the simplicity of the machinery, then you do need to know what parts are best for effective splitting power. Gas and electric splitters utilize a hydraulic pump which is the integral component of hydraulic power. If you were wondering what size hydraulic pump for a log splitter you need, this article explains below its use and what to look for.

Log splitters are powerful machines that provide a splitting pressure to logs of various sizes. Almost all splitters use hydraulics whether it is pressurized via an electric, gas, or manual power source. These hydraulics feed a splitting wedge of your model of choice to make short work of just about any size log you you need to cut down to size.

One of the simplest hydraulic systems you can find in use is a log splitter. The basics of hydraulic pressure utilize an engine, oil pump to create oil pressure, a hydraulic cylinder that works with a valve for splitting power, and tank to hold and feed oil through the system.

If you are serious about making your own backyard log splitter, then you want to have, at a minimum, the following components to provide the right amount of force and power for basic splitting of averaged sized, seasoned logs:

But you may want a bit more force for heavier workloads, which is why I’ve explained below how a pump can help determine your splitter’s speed, and influence the cutting force. Read more about how a log splitter works, how to care for it, and what you need to build your own.

Mentioned multiple times above is the use of a two-stage pump that is most common for a hydraulic log splitter system. This is because it uses two different sets of gears doing the pumping to keep you machine running smoothly and providing the power you need at the speed you desire.

Although a two-stage pump is the best option for your log splitter, you can manipulate the amount of force it exerts through which size cylinder you choose. To calculate your own splitter’s force and speed based on the choices you make, you can use this handy calculator tool.

The entire splitting system is dependent upon the pump that consists of two pumping sections and an internal pressure sensing valve. One of these sections generates the maximum flow rate rated at at lower pressure that is used to draw the piston back for the system to reset after splitting. The other section provides the highest possible pressure to generate maximum splitting force.

Knowing the maximum pressure generated by a pump determines the splitting powerof the pump, and one thing you will notice is that most companies are fairly generous in their tonnage claims and round up more often than not. To figure the tonnage provided by the splitter, simply multiple the maximum pressure of the pump (a two-stage pump applies about 3,000 PSI), by the total surface area of the piston in square inches. The resulting number is the total available pressure.

You also can determine the cycle time of a piston to figure how quickly you can work through a pile of logs. To move a 4 inch piston 24 inches (the common piston length) you need 301 cubic inches of oil. Since a gallon of hydraulic fluid takes up 231 cubic inches, you need to pump, at a minimum, 1.5 gallons of fluid to push the piston in one direction.

The flow rate of the pump is dependent on the size of the engine powering the system. If your engine is capable of providing an 11 gallon per minute rate, then it will take approximately 20 to 30 seconds to cut, and around 10 seconds to reset. Common horsepower minimum requirements for a two-stage pump are:

For a dependable machine, you want to incorporate a two-stage pump to work with whatever size engine and cylinder you decide upon for cutting wood. These keep your splitter working smoothing and efficiently, and allow you to dictate speed and force to handle whatever size job you have in mind. If you have any further questions, or want to add to this information, please do so below. And, as always, please share.

Are you trying to buy a new hydraulic pump for your log splitter or do you need a perfect replacement pump kit for your wood splitter? Then, you should start your buying journey by reading this post. In this article, we’ll review the six best log splitter hydraulic pumps in 2022.

We compiled our list of the best gear pumps available after considering thoroughly their construction, splitting power, the flow rate for cycle time, operating speed, safety features, and overall benefits. We also included a buyer’s guide, FAQs, and summary to help you make a well-informed choice that suits your log splitter’s requirements and needs.

Log splitters are powerful machines designed to split logs efficiently. The machines offer effective splitting power to logs of various sizes. Almost all log splitters (including electric and gas types) use a hydraulic pump which is the integral component of a hydraulic machine that helps achieve the basic splitting of logs. The major components of a log splitter include an engine, hydraulic oil pump, valve, and hydraulic oil tank.

A typical hydraulic pump used for a log splitter is designed to feature a 5 hp gasoline engine, two-stage pumping sections, a hydraulic cylinder (4” diameter, 24” long), a 20 tons rated splitting force, and a 3-5-gallon hydraulic oil reservoir. Log splitters often use a two-stage pump to generate the right amount of pressure and flow rate required for splitting logs.

It’s tough to pick one product when you have many products from different brands making similar claims. So, we’ve done the hard work for you. Here are the best six pumps for a log splitter on the market. After reading this review, making a decision will become easier for you.

The RuggedMade 11 GPM 2-Stage Hydraulic Log Splitter Pump is perfect for log splitters with a rated force not up to 35 tons. It’s built with aluminum material for a longer service lifespan.

This hydraulic pump boasts up to 3000 PSI capable of powering log splitters and outdoor power requirements that range from 5 to 37 tons, depending on the hydraulic cylinder diameter (inner).

The two-stage pump operates at a maximum speed of 3600 rpm for faster cycle times during unloading. It’s preset to gear down mode at 500 PSI to help relieve the pump’s pressure; thus, ensuring the proper functioning of your splitter hydraulic system.

The Yaegoo 11GPM 2-Stage Hydraulic Log Splitter Pump is suitable for any log splitters application. It features a flow rate of 11 GPM capable of creating a stream of high-pressure oil required for generating maximum splitting force.

This two-stage hydraulic pump works at 3000 PSI to ensure effective splitting power without a loss of pressure. It’s built to automatically switch from high-pressure to low-pressure at 500 PSI for quick drawing back of the piston after splitting the log.

This log splitter hydraulic pump is ideal for log splitters with a rated splitting force of about 35 tons. It supports both vertical and horizontal applications.

The Bestauto Log Splitter Pump Kit is a suitable replacement pump kit for log splitters. It’s built with extrusion aluminum material that can resist wear and tears for an extended service life cycle.

This kit comes with a two-stage hydraulic pump, pump bracket, and jaw coupler. The 2-stage hydraulic pump works at 3600RPM maximum to ensure the fastest possible cycle times. The pump offers 13 GPM flow at 3000PSI maximum operation pressure to provide quick oil output.

The pump bracket and jaw coupler make lifting, pressure type, elbow, bending row, straightening, cutting, assembly, and more possible for a hydraulic log splitter. It’s compatible with a wide range of engine sizes.

The RuggedMade 16 GPM 2 Stage Hydraulic Log Splitter Pump features a body built with aluminum material for longevity. It’s designed to contain two pumping stages and a bypass valve to allow for efficient log splitting.

The first stage of the pump generates 16 GPM at 650 PSI required to reset the entire splitting system back after splitting. The second stage of the pump delivers 3.5 GPM at 2500 PSI to generate the maximum splitting force required to push the piston into a log for effective splitting performance.

The TooTuff Log Splitter Build Kit is a perfect kit for a DIY splitter project. It provides two-stage pump action to allow for maximum log splitting efficiency. The 1st pumping stage operates with a maximum flow rate (13 GPM) at a lower pressure of 650 PSI to help ensure a quicker cylinder return position.

In the second stage, the pump switches to a lower flow rate (3 GPM) and higher pressure (2500 PSI) to generate the maximum effective splitting power to split the log.

This hydraulic pump provides faster cycle times (16 GPM at 3600RPM) and higher possible pressure (up to 4000 PSI) with a small engine or most 8-14HP gas engines.

The Bestauto Log Splitter Pump Kit consists of a powerful hydraulic pump and hydraulic tools such as a jaw coupler and pump bracket. This hydraulic pump is built with sturdy and durable materials that can withstand even harsh environments.

The pump offers two-stage hydraulic actions to keep your log splitter running correctly. The 1st stage of the pump is preset to operate with a maximum flow rate of 16 GPM at 650 PSI for quicker withdrawing of the piston after the log has been split.

While the 2nd stage of the pump operates with the lower flow (3.5 GPM maximum) at higher pressure (2500 PSI maximum) to ensure excellent splitting efficiency.

The materials used in the construction of a hydraulic pump for log splitters would determine the longevity and performance of such a pump. Log splitter pumps built with high-quality materials such as aluminum have a longer service lifespan.

It’s important to ensure that all the components of the pump you intend to buy are built with materials of high strength and hardness that can resist wear and tear over multiple uses. It’s also important to check if the pump’s quality is well-assured by the manufacturer so that you can have a great user experience.

The splitting power of a hydraulic pump for log splitters is largely dependent on the maximum pressure that such a pump can generate. The amount of pressure that a pump generate vary from brand to brand.

However, the higher the pump’s maximum pressure, the more effective its splitting power. We don’t recommend more than 3000 PSI, which is the practical maximum pressure that most 2-stage gear pumps required for excellent log splitting.

The flow rate of the hydraulic pump determines the periods of time the pump would take to work through a pile of logs. The pump’s flow rate is largely dependent on the size of the engine powering the system.

A two-stage hydraulic pump for log splitters often requires minimum horsepower such as 5-7 hp engines with 11 GPM pump, 6hp engine with 13 GPM pump, 8 hp with 16 GPM pump, and 11 hp with 22 GPM pump.

You don’t have to worry too much when choosing a hydraulic pump based on the flow rate as virtually all log splitter pumps out there are rated for the same pressure.

It’s important to know that the operating speed of the hydraulic pump is hugely dependent on the hydraulic flow rate (GPM). Generally, larger pumps produce more flow which means more operating speed. However, bigger gear pumps require larger engines or powerful engines to drive them. Small pumps produce less flow but don’t require more horsepower to function properly.

The safety valve ensures smooth operation and performance of the hydraulic pumps. It helps to control the maximum pressure created by the hydraulic pump. Without a safety valve, most hydraulic pumps will build pressure up to a point that something break. Uncontrolled maximum pressure is likely to break your hydraulic hoses, garden hoses, hydraulic pressure hoses, the cylinder, or the pump itself.

To ensure the entire safety of your hydraulic system, you should go for 2-stage pumps with features such as a hydraulic relief valve, check valve, directional control valve, unloader valve, or hydraulic valve. Any of these safety features would help keep your pump’s pressure in check.

Besides, you should check if the pump you want to buy comes with a return filter, filter element, or filter head. Any of this would function to keep dirt out of its hydraulic reservoir (fluid reservoir).

Most simple wood splitters use a 2-stage gear pump for efficient log splitting. The two-stage pumps give log splitters effective splitting power using small engines. They can help generate the highest possible pressure required to keep most log splitters working smoothly and efficiently.

The approved fluid types for the hydraulic system of most wood splitters are AW-32 10-Weight (ISO 32) and AW-46 20-Weight (ISO 46). These hydraulic fluid types help lubricate your gear pumps and other hydraulic parts for protection against corrosion and weariness during extreme cold and heat.

We recommend changing the hydraulic oil in your log splitter every 100 hours of work. Regular changing of the hydraulic oil in your log splitter would help improve the performance of your log splitter hydraulic system. In addition to replacing your log splitter hydraulic oil as recommended, you also need to change your filter to keep dirt away.

A single-stage hydraulic pump features only a single pumping section or setting. It’s designed to generate just one flow rate (maximum GPM) at one maximum pressure to create the maximum splitting force. While a two-stage hydraulic pump features two pumping sections or settings. It’s designed to generate two flow rates at two different pressure levels.

A two-stage pump automatically switches to its ‘high-pressure/low-flow stage to split the blog (something that can’t be achieved with a single-stage pump). Two-stage pumps generally save splitting time than its counterpart (that’s one-stage pumps).

Look no further than this review if you would like to try out the best hydraulic pumps for log splitters out there. Any of the review gear pumps are capable of giving your splitters the power required to split log efficiently. We’re certain that you won’t go wrong with choosing to buy any of the above products. They are the best anyone can find on the internet at the moment.

For the people who have absolutely no idea about what these log splitters are, in simple terms, they can be called machines that chop wood using automation (or manual) power.

The primary purpose is to break these logs into pieces to aid their transport. The purpose of designing the log splitter is to simplify log splitting via automation (or manual) power.

Log splitters are phenomenal in their work, and the design aspect of log splitters is their main highlight. To achieve this automation, efficiency, and effectiveness, all these log splitters use hydraulics.

This two-stage hydraulic log splitter pump is the base of the hydraulic system. The hydraulic system is used to pressurize and create the force for splitting the wood.

This makes the log splitter pump the essential part of the log splitter. Whether you are well-versed with log splitters or have hardly heard about them, go through this article, and you will surely understand what size of log splitter pump you should use.

Log splitter pumps, as previously discussed, are a very crucial element. Thus, choosing the right kind of hydraulic log splitter pump becomes very important. The best way to go with this is by choosing the right size and quality materials for the log splitter pump. This will ensure high efficiency and effectiveness.

Before you make the decision, do analyze accordingly concerning your needs and log splitter. The size of log splitter pumps influences not only the performance but also the cost. Thus, the decision of choosing the size of hydraulic log splitter pumps depends upon three major factors:

Before deciding the size of log splitter pumps, it is essential to understand the hydraulics to determine the correct size based on the principle of log splitter pumps.

Hydraulic log splitter pumps work according to the phenomenon of hydraulics. Pascal’s law (Principle of hydraulics) governs hydraulics. It states that if you apply pressure to a particular point of a fluid (closed/confined), the pressure transmits to every other fluid point (with no losses).

Pumps convert one form of energy to another. As the name suggests, hydraulic pumps convert mechanical energy to hydraulic energy. For this conversion, hydraulic pumps use flowing water.

Using flowing water, these hydraulic pumps create a hydraulic system. This system is complicated, but in simpler terms, it provides force in a specific area, basically what we call pressure.

Two-stage hydraulic pumps are usually used as log splitter pumps. This complex system can be explained using an analogy. Consider the working of a vehicle, and it displaces itself irrespective of the heavyweight. It uses power for displacement.

This is precisely what happens in a log splitter, except that it happens at a smaller scale. Thus, the pump utilizes the conversion of the energy for running the log splitter.

Now that you know the log splitter and hydraulic pump details, we can discuss the size of the log splitter pump. Why should we be bothered about the size of the log splitter pump? The reason is that the size affects the speed and force (splitting).

Bigger the size of the log splitter pump (basically the pump cylinder’s size), the bigger the splitting force. This helps in the useful splitting of more extensive woods. But with the increase in the size of the hydraulic pump, it also requires more fluid. The requirement of more fluid decreases the speed.

This is the reason why the size of log splitter pumps becomes so essential. You can either choose the speed of splitting force. If you choose to increase one of the two-parameter, then the other one decreases.

To choose the best and correct size of your log splitter, you need to decide to improve either pump speed or splitting force. There are different size pumps available in the market according to your requirement.

Pumps available in the market are based on GPM (Gallons per minute). The higher the GPM, the smaller is the cylinder. The splitting force depends upon the cylinder. The higher the GPM, the smaller is the splitting force. To make it more transparent,

If you are interested in making a log splitter, which is possible as the calculations required for designing, parts required, and technique to make a log splitter is available. It can be employed if one shows interest in it. Only go for the DIY option if you are well-versed with machinery.

The engine of the log splitter works on the basics of hydraulics. The pump creates the driving force, and the hydraulic cylinder works in unison with the valves influencing splitting power and speed.

The engine used must be of 6-7 Horsepower. A two-stage hydraulic pump (about 3000 PSI) must be employed of 11 GPM. The standard hydraulic cylinder of 4-inch diameter and 24-inch length/height. Around 10-12-gallon capacity of the oil tank.

Note: If you want to play around with the values and choose the best according to your requirement, then use this calculator tool by international hydraulics.

Finally, it is your choice! As you know that you can either have a good speed or high splitting force, you must make your own decision with the size of log splitter pumps. You do not need to worry a lot as the size is only one aspect to look at, but the right decision about the size is always useful in usage.

The choice of DIY or buying one from the market is also your choice. If you are well-versed with calculations and machinery, then go for it as log splitters are expensive in the market.

If you know why you are employing a log splitter, it will help you make a better decision. For example, if you are one of those campers who requires a log splitter in his camps for firewood, go for the speedy ones (small cylinder size). The reason is that you would want to split wood faster instead of splitting larger pieces.

Irrespective of whether you buy a branded log splitter or DIY, they require regular maintenance and cleaning. For better results, go for the two-stage hydraulic pumps (even if they are a bit expensive).

If you follow the above tips, then the log splitter works effectively and efficiently. Taking the right decisions can help you enforce the right speed and optimum splitting force required for your log splitting.

Brand new 19GPM, 2 stage hydraulic replacement pump for log splitters. Fits many different applications, including newest models sold at Tractor Supply Co.

- The 2-stage pump can give you faster cycle times and higher possible pressure with a small engine. Excellent for use on log splitters. 85% efficient.

- This 2 stage pump can give you much faster cycle times and higher possible pressures with a small engine. Excellent for use on log splitters. 85% efficient.

This product is a Hi-Lo cast iron hydraulic gear pump with max pressures of 900 PSI for the low pressure and 3000 PSI for the high pressure pump. Typical applications for this 13 GPM hydraulic pump are log splitters and presses, where alternating low and high pressures are required to move a cylinder.

This product is a Hi-Lo cast iron hydraulic gear pump with max pressures of 900 PSI for the low pressure and 3000 PSI for the high pressure pump. Typical applications are log splitters and presses, where alternating low and high pressures are required to move a cylinder.

The cylinder is driven by hydraulic oil, under pressure, produced by a hydraulic pump. An engine, or electric motor, drives the pump shaft, and supplies the power for the system. The oil from the pump runs to a hydraulic valve, which provides control over the movement of the cylinder.

The oil source is a hydraulic reservoir (tank) which is connected directly to the inlet port of the pump. Most use AW32 viscosity (approx 10 wt.) hydraulic oil, which is of course an important part of any hydraulic system. There is a vented filler cap on the reservoir which allows air to “breathe” in and out. A simple air filter in it keeps dirt out.

There is, or should be, a filter in the return line from the outlet of the valve to the reservoir. (Suction strainers in the inlet line are not a substitute for a return filter and are not recommended.)

A hydraulic relief valve controls the maximum pressure which can be created by the pump, and is a safety valve. It is usually located within the housing of the directional control valve. It is rarely in the pump. Without a relief, most hydraulic pumps will build pressure until something breaks, like a hose, or the cylinder, or the pump itself.

Most log splitters use a 2-stage gear pump which is a special type of hydraulic pump. They are rarely used in any other hydraulic systems. But they are widely available and relatively cheap because so many are sold for logsplitters.

Let’s start with the basics. Gear pumps are the most common, and least expensive type of hydraulic pump. They consist of 2 shafts, each with a gear which meshes with its twin to drive oil from the inlet port to the outlet or pressure port. Oil is trapped in the cavities between the gear teeth and carried around the outside of the gear toward the outlet port. The meshed gear teeth in the center keep oil from returning to the inlet side. One shaft sticks out of the housing and is driven by the engine. The other shaft is hidden within the pump housing. The one gear drives the other.

Two stage pumps give splitters great performance using small engines. A 2-stage pump consists of 2 gear pumps in a single housing, and a bypass valve. One gear set is about 3 times the size (length) of the second. When the valve is in neutral & system pressure is low, both gear sets are pumping oil into the system. With a “16 GPM” pump, they will pump 16 GPM when the pump shaft is rotated (by the engine) at 3400 RPM. That is, the combination of the outputs from both gear sets equals 16 GPM.

When the valve is shifted it moves the cylinder quite quickly. But when the log hits the wedge, the resistance increases, and pressure is backed up against the pump. Now the bypass valve comes into play. When the back pressure reaches 700 – 800 PSI, oil from the larger set of gears is allowed to pass back to the inlet side of the pump (at almost 0 PSI) rather than being forced out the pressure port. So the only oil being forced out is from the small gear set. This takes a lot less horsepower and allows the use of a reasonably small engine to develop the high pressure necessary to split wood, while giving the cylinder good speed when not under a heavy load (which is most of the time). The opening and closing of the bypass is automatic, activated by the oil pressure. It’s so smooth it’s usually difficult to notice it is happening. So 2-stage pumps give our log splitters the best of both: high pressure when we need it, and high speed the rest of the time.

We sometimes see home made log splitters with single stage pumps, often reused from another type of machine. They are usually quite slow unless a much bigger than normal engine is used.

The cylinder is the “actuator” of the system: it converts the hydraulic pressure and flow into force to split the wood, and speed to make it efficient. The larger the cylinder diameter the more force (tonnage) it puts out, but the slower it will go: it takes more oil to fill, and so takes longer.

The most common size for log splitters is “4 x 24″, 4″ bore by 24″ stroke. With 2500 PSI from the pump it can exert over 31,000 lbs of push force. To compare, a 5″ bore cylinder can produce 49,000 lbs force with the same pump, over 1 1/2 times as much. But the 5” cylinder will go 36% slower, which is why they are not common on ordinary splitters.

Yes, I know, there are plenty of log splitters rated for much more force. And my 4 cylinder Toyota may be rated for 140 MPH. It’s a sales game. The big numbers are theoretical maximums, not practical working pressures.

1. Pushed one way it shunts oil from the pump to the base port of the cylinder, causing it to extend. And it simultaneously allows oil from the rod-end port of the cylinder to flow into the return line.

2. When let go, the spool springs back to the neutral position; the oil from the pump is allowed straight through to the return port where it is recycled back to the tank, and the cylinder ports are blocked so the cylinder is stopped and held in position.

The relief valve consists of a heavy spring with a compression adjustment screw, and a ball or poppet against a seat. This is in a channel between the pressure inlet port and the return port, with the ball or poppet blocking the flow. If the oil pressure reaches the adjustment setting, perhaps 2500 PSI, it overcomes the spring pressure, the poppet backs off, and oil from the pump is allowed to bypass directly to the valve outlet, thus limiting the maximum oil pressure in the system. At normal working pressures, the relief remains closed and is not involved in the circuit.

The return detent holds the spool in the cylinder return position so the operator can let go of the handle while the cylinder returns. But it is a detent with a special self-cancelling feature: when the cylinder “bottoms out”, the oil pressure increases suddenly automatically releasing the detent so the valve spool can spring back to neutral. That’s what’s different from a standard detent, which does not kick off by itself.

The hydraulic oil for the system is stored in a tank, usually steel. Reservoirs serve two important functions: They allow the oil to settle any air bubbles and contamination particles; and they allow the oil to cool while it’s not circulating.

To provide sufficient cooling, the tank should be sized to hold at least one minute’s worth of oil. (16 gallons for a 16 GPM pump.) Oil which is too hot, 180F, will harden seals, and will be too thin to lubricate the spinning pump parts, causing early pump failure. We recommend 150F as the working maximum oil temperature.

The suction and return ports should be on the sides of the tank, a couple of inches above the bottom to avoid any sludge which may have settled there. The suction line should be low enough to never ingest any air, and the return should be low so as not to stir any air into the oil. Further, the 2 ports should be separated enough to avoid the hot returning oil from being immediately sucked back into the pump line.

Every good hydraulic system has a filter to remove fine contamination particles from the oil. The recommended rating is 10 microns, (10 microns equals 0.00039 inches; about 1/5 the diameter of a human hair). A filter this fine would plug the suction line, so it must be installed on the return, typically right at the tank return port.

Suction strainers in the tank are 100 micron or more, so can not catch the fine, damaging particles like the return filter. And if they get plugged they may starve the pump, greatly shortening its life. They are not recommended.

Hydraulic oil is blended with chemical additives beneficial for hydraulic systems. They help resist wear, shed contamination, maintain viscosity when cold, resist foaming, rust and oxidation, etc. Typical viscosity is around SAE 10, usually labelled AW32.

Hydraulic oil is not subjected to the burning temperatures of combustion engines, so it usually lasts a long time. The recommendation is to change oil if it is excessively dirty, or milky (water contamination) or smells bad or burned. If not, it’s better to just change the filter and save the cost of an oil change.

How to get more force? Either more pressure, or a larger cylinder. The pressure you probably can’t change much. Check the relief setting on your directional valve. It controls the maximum. We don’t suggest more than 2500 PSI, which is the practical maximum for most gear pumps. Yes they are sometimes rated at 3000 PSI or more. But that’s like driving your car 125 MPH. It may be able to do it, but all the time? Not such a good idea. Virtually all logsplitter pumps are rated for the same pressure. What’s the difference between pumps? Bigger gears, which produce more flow, which means more speed. And requires more horsepower to drive them. To get more force, you’ll need a larger bore cylinder. If you want the same speed as a smaller cylinder, you’ll need a larger pump, and probably a larger engine to drive it.

How to get more speed? Either more flow (GPM), or a smaller cylinder. The smaller cylinder won’t require more power, but will produce less force. More flow comes from a larger pump. So you’ll get the same force but will need to supply more horsepower to the new pump.

One other factor to consider for log splitter cylinders is the rod diameter. The larger the rod, the faster the cylinder will retract. (It takes less oil to fill the return end of the cylinder.) Of course it also increases the cost of the cylinder, but if you have the choice, choose the cylinder with the larger rod.

So if you are looking for a Hydraulic Component for the Earthmoving, Manufacturing, Transport and or the Marine Industry you have come to the right place.