How to repair a hydraulic bottle jack (and not only)
Many car owners, and not only them, think about the question of how to repair a hydraulic jack with their own hands without going to a workshop.
The hydraulic jack is a portable lifting device designed for heavy objects.
The jack is one of the most important tools, you can’t do without it, for example, when repairing a car. With the help of a jack, the car body is raised to a sufficient height to be able to carry out repairs.
Three methods:
- Add oil to the horizontal jack
- Add oil to a vertical jack
Hydraulic jacks are used to lift heavy objects such as cars. They are standard tools in car dealerships. Hydraulic jacks require fluid to push pistons that lift heavy objects off the ground. You can buy a hydraulic jack and the oil necessary for its functioning in an auto parts store. Use these tips to know how to add oil to a hydraulic jack.
Scope of application
A manual jack, made by your own hands, greatly simplifies repair, maintenance and tuning work related to vehicles, will help in the construction and restoration of capital structures. Having a compact jack saves the car owner from having to visit a service center or buy a factory-made device. The lifting force of the mechanism allows the following manipulation of the load:
Planning to make a jack, it is necessary to take into account that the device can not lift loads “from the floor”, its design can not make adjustment of the lowering level, transportation of the mechanism should be carried out only in an upright position. The hydraulic system requires constant maintenance.
In the process of work on the device it is also necessary to take into account that the factory jack will work cyclically, and in case of breakdown repair measures will require significant financial expenses. Fixture, assembled in your garage, in the case of failure can be replaced by another device of own assembly, but its degree of reliability is reduced by several times.
The principles of hydraulics
For practical realization of the portable jack scheme, the hydraulic jack is equipped with a system arranged on the principle of communicating with each other vessels. The principle of operation is as follows:
- the pressure pump supplies liquid from the reserve vessel to the main vessel;
- The work process creates pressure inside the system;
- pressure moves the piston.
Due to the small number of parts contained in the design, maintenance and repair of the device does not require the use of special tools and production equipment. All components of the device have a significant service life.
As a part of the hydraulic jack jack there is a reserve vessel with a lever system, the working piston cylinder with a plunger, a supporting part for compensation of the mechanical pressure arising during the lifting of the load. Jack design provides for the load to be lifted to a permissible height equal to the distance between the base and the top of the piston rod.
In the device of the rolling jack includes three important components, the functionality of which is formed by force loads on the movable parts of the device. The principle of operation of the component parts is similar to other types of compact lifting equipment, the design of which contains:
To pump the bottle-type jack, mechanical action is directed to the levers, the increase of which is possible due to the valves. The plunger transfers oil to the receiver by means of the movement of the piston, the return of the liquid medium and the return of the piston to the starting position is performed after the valve has been opened and the oil has been transferred to the reserve tank.
As a working fluid of the bottle-type jack is used filtered machine oil, which allows to work with objects weighing up to 100 kg. The main advantage of the device is the significant size of the support platform. The hydraulic lifting device of the bottle model is manufactured in two modifications:
- Single rod units of simple design (used in car repair, construction, pipe bending and cutting);
- Two-rod vertical and horizontal mechanisms.
According to physical and mechanical features the principle of action of various models of devices is aimed at ensuring the convenience of repair of vehicles, trailers, supporting structures, elements of barriers and other objects that have weight, unbearable for a man.
Fault detection
The piston rod extends to the proper height, but then slowly (without load) descends. in this case the cause is most likely a by-pass valve and damaged O-rings, so the correct pressure is not maintained.
If the jack does not lift all the way up, it means that the working stroke has decreased. Corrosion on the rod and cylinder surface mirror is the culprit at this point. If a load to be lifted exceeds the jack capacity (indicated in tonnes on the jack passport and on the housing), there is a possibility of damage or distortion of the jack stem.
In order to keep the jack in good working order and not to break down, the following rules should be remembered:
- The hydraulic fluid needs to be replaced twice a year.
- If the jack is used every day, the hydraulic fluid should be changed monthly.
- In extreme cases any hydraulic fluid can be used, but in wintertime it is recommended to use synthetic oils specified by the manufacturer of the device.
- Store the jack in a warm, dry place to prevent the oil from thickening in winter.
- It is not advisable to operate the jack in winter in cold weather, because it may simply stop working.
A lot of time and money can be wasted to repair the damage, so it is easier to follow the instructions for operating the hydraulic jack, and then it will last a long time and help lift a load more than once.
When to Repair a Jack
Hydraulic Jack Construction
Jacks of this variety, as well as any other equipment, need periodic maintenance, in addition, as a result of various failures may need to repair the device.
So, the cylinder of the device needs to be replenished from time to time as oil can leak out through the seals and packings while the jack is working. Lack of oil reduces the jack’s performance.
In addition to oil leaks, the breakdowns of the device may consist in its jamming when lifting a load, air entering the cylinder. In addition, frequent failures also include the inability to lower the tool after lifting, as well as failure of the mechanism to operate even under light loads. In these and many other cases you will need to repair the hydraulic jack, which in some cases can be done with your own hands.
When the jack needs to be repaired
Hydraulic jack design
Jacks of this variety, as well as any other equipment, need periodic maintenance, in addition, as a result of certain breakdowns may need to repair the device.
So, it is necessary to top up the cylinder of the device from time to time, because during the operation of the jack oil may leak out through the seals and glands. Lack of air reduces the efficiency of the device.
In addition to oil leaks, the breakdowns of the device may consist in its jamming during the lifting of the load, air getting into the cylinder. In addition, frequent failures also include the inability to lower the tool after lifting, and the failure of the mechanism to operate even under light loads. In such and many other cases you need to repair the hydraulic jack, which in some cases can be done with your own hands.
How to fill up the oil and pump the jack?
Oil is poured through the neck on the side of the housing. This same neck is also the level. Pour the oil, then it is necessary to pump the jack.
- Lift the piston rod to its highest position, without load, by operating the lever
- Then it is placed on its side with the filler plug on top
- The plug is loosened and the piston rod is pushed vigorously into the cylinder. The air must be expelled from the working chamber.
- The plug is closed, and 10-15 full lifts and lowers the rod with a load of 40. 45 kg.
- Overloading should be performed on the last cycle and if the jack does not hold the cylinder, the procedure should be repeated.
Troubleshooting
Oil leakage is the main problem that causes the jack not to lift up to the end (with a small leakage) or at all (with a significant leakage). Because of this air enters the cavity, and then the jack works at a low force or refuses to work at all. Leakage in the hydraulic system can be prevented by routine maintenance, check oil level. If the level is low, simply fill up the fluid to the required level.
A drop in the oil level can occur naturally or as a result of worn or damaged oil seals and oil seals. There is no simple oil refill and the o-rings have to be changed.
Air is leaking into the hydraulics due to lack of fluid. This problem can be solved by pumping: you need to unscrew the plug of the oil reservoir and the bypass valve, and then simply pump the system, that is move the lever up and down until the liquid flows into the main cylinder.
Corrosion on the pistons, rods and cavity is often the cause of failure. To find out the detailed cause and repair it is necessary to disassemble the device.
A bent rod is also a common reason why the jack does not lift or works with a jerk. In this case, you can change the element, taking an analogue of the old model, or buy a new part. In most cases, such malfunctions cannot be repaired at all, even in a workshop or service center. This is because the spindle usually bends when subjected to shock loading, which damages the main body components. In this case, it is cheaper to buy a new unit, without repairing or replacing individual parts.
It is better to remove the dirt with kerosene.
When the bypass valve is deformed or just has dirt accumulated in it, the ball of the valve sits tightly in its seat and hydraulic fluid leaks through it. In this case, you will just have to replace it and change the old (contaminated) oil for the new one.
Changing oil
Repair and maintenance.
To service a bottle jack, it must be disassembled. There is no need to worry about getting splashed with oil from the high pressure. It is quite possible to do it yourself. The first thing to do is to drain the oil. Drain through the filler hole, and if it is absent through the bypass valve, to do this unscrew the upper hex nut and completely unscrew the lower cock. Remove the housing, check its tightness, assess the condition of the lower rubber ring. These parts don’t carry any load, they are just a reservoir for liquid. Then unscrew working cylinder and remove piston. All carefully inspect for rust. In case of its detection we get rid of it as carefully as possible. Unscrew the ram, check its performance, inspect the o-rings. There must be no iron shavings inside and no dents. The worn seals should be replaced with new ones. Don’t forget to wash thoroughly all valves from dirt and various deposits. Reassemble, that’s all the repair is done.
Repair rules and parts selection
Hydraulic jack repair begins with disassembly. All parts of the product have screw joints, so it is necessary to arm using wrenches.
- It is necessary to drain the oil. For this a special container is prepared.
- The piston and valve are removed. Visually inspect them. All dirt and rust is removed.
- The cause of the malfunction can be a deformed stem. The jack can not lift the load. In this case the part needs to be replaced.
- Gaskets must be inspected carefully. If no defects are found during visual inspection, it is still better to replace them. Often microscopic imperfections are not visible, but they are the cause of the malfunction.
- The oil valve is checked. Stuck particles are removed. The ball is in the wrong position because of its presence and oil is leaking.
All parts of the disassembled appliance are washed in a special liquid. Defective parts should be replaced. Parts selection is performed for this purpose. All new construction elements must have the same parameters. Repair kits are available to replace a small structural component. They include parts and the gaskets between them. Reassemble in reverse order.
Change and rules of the oil filling
Before pouring in the new oil the old one should be completely removed. If there is any flushing fluid, it should be removed as well.
Before replenishing the oil, all air trapped in the system is removed. The discharge valve is opened and the unit is lowered down. Then at least 5 pumpings should be made. Remove the bolt from the filler neck and pour in oil up to the required level through the nozzle. Then the pumping is repeated and the oil refilled. It is important to bleed all air from the system. As soon as the oil is no longer bubbling and the oil level is correct, the jack is ready for operation.
Rules for operating the 5 and 12-ton jack.
If the jack is operated properly, the number of breakdowns will be drastically reduced.
To do this, the following rules must be adhered to:
- Do not lift more than the maximum permissible load.
- Operate smoothly, without jerking.
- Installation should only be carried out on a flat surface.
- Lubricate all movable joints before work.
- The machine is inspected externally for cracks or oil leaks.
- Check the oil level, which must be brought up to normal.
To keep the hydraulic jack running smoothly, monthly maintenance is required. As the product is subjected to continuous heavy loads, all parts require lubrication. It is important to avoid dirt, which leads to jamming of the device. The device is stored in the lowered state.
Rules of repair and choice of spare parts
Hydraulic jack repair begins with disassembly. All parts of the unit have threaded joints, so wrenches are needed.
- The oil must be drained. Prepare a special container for this purpose.
- The piston and valve are removed. Visually inspect the appliance. All dirt and rust should be removed.
- Deformed piston rod may be the reason of malfunction. The jack is unable to lift the load. In this case the part needs to be replaced.
- Gaskets must be carefully inspected. If the external inspection does not reveal any defects, it is still better to replace them. Microscopic faults are often not visible, but are the cause of the fault.
- The oil valve is checked. Clean up any dirt that may have stuck to the unit. Because of its presence, the ball takes the wrong position and oil leaks.
All parts of the stripped machine should be rinsed in a suitable liquid. Defective parts are replaced. For this purpose there is a selection of spare parts. All new parts must have the same specifications. Repair kits are available for replacement of small parts. They include parts and gaskets between them. Reassemble in reverse order.
How to change and fill up the oil
Before filling up with new oil, the old one must be completely removed. If there is flushing fluid present, it is also removed.
All air that is present is removed before a new one is put in. The outlet valve is opened and the unit is lowered down. Then at least 5 pumping operations must be carried out. The bolt is removed from the filler neck and oil is poured through the nozzle to the required level. Then the pumping is repeated and the oil is refilled. It is important to bleed all air from the system. As soon as the oil stops bubbling and reaches the proper mark, the jack is ready for use.
How to fill the jack with oil. step-by-step diagram
Flushing the Mechanism
To fill the jack with oil, you must first unscrew the cap and drain the old fluid. The next step is to clean the mechanism with a flushing fluid, which can be purchased at any construction store. It is difficult to wash a jack completely, especially a beginner, because you have to pour the liquid at least two or three times, then the pumping is carried out and the liquid is added and pumped again. Drain the old oil in the same way. so that not a single drop of the old fluid remains inside the mechanism.
Fill up with oil
The container must be filled with oil to the end, i.e. until the fluid has reached the required level. Jack in this case set on low position. To lower the rod to the lower position, be sure to turn the screw-cock until it reaches the “drain” position. screw in the plug and pump for five times, then add oil and screw in the plug again. There will not be enough oil in the cleaning process every time, so pump until the “fuel” of our jack reaches the required level and bubbles stop appearing on the surface of the fluid.
Instructions for the correct pumping of the jack device
Hydraulic jack oil filling diagram.
Among jacks advantages are rigid design, as well as the height of load lifting from the ground, the greatest lifting capacity with smooth running, the minimum pick-up height. All of these advantages give a high degree of efficiency.
Causes of failure of the equipment can be any. For example, prolonged use of the device may cause air accumulation in the form of bubbles. This reduces the efficiency of using the jack, that is, its efficiency drops sharply. This is caused by air entering the hydraulic mechanism due to a shortage of hydraulic fluid.
Pumping and Jack Troubleshooting
The following steps will bring the unit back to its original condition
- Start pumping when the by-pass valve with oil reservoir plug is open.
- Pump the pump of the device a certain number of times, which will displace all the accumulated air from the working cavity into a special container for the liquid.
- Carry out the closing of the hole of the oil tank and the bypass valve.
Otherwise the above steps, according to the instruction, are repeated.
How to properly pump the jack using a different algorithm
Corroded parts should be replaced.
Since the above method of jack pumping is not the only method, the following steps can be performed in stages:
- If the jack is slow to lift the load or if it is completely defective, the presence of air in the cavity of the device is determined.
- The locking needle should not be unscrewed by 1.5-2 turns, and the jack plunger is lifted by the screw to the upper point, which is the extreme point, and then it is lowered again to return to the position from below.
This last operation should be repeated 2 to 3 times. To prevent this problem, check periodically the level of liquid in the jack. If it is not enough, oil must be added.
Pumping of the jack should be repeated after the contamination has entered the working cavity. Unscrew housing head to remove contamination, then pour kerosene into the base of the housing. Then the jack is pumped, having unloaded the locking needle beforehand. After the operation is complete, the kerosene is removed and the working cavity is filled with clean hydraulic fluid.
In general, the algorithm is as follows:
- Pour in the oil and close the box.
- The piston should be pumped by raising it until it fails.
- The plug is unscrewed and the piston is pushed in, so that the air can escape from the cylinder.
- Add oil by closing the plug and t.д.
This is done until all the air is out and the hydraulic oil comes out in accordance with the pumping of the brakes.
Extend service life
Any tool that breaks down is often an unpleasant, even dangerous, experience that involves loss of time and money. Failure of the elevator, at the most inopportune moment, can cause unnecessary problems, so it is advisable to take extra responsibility when working with this tool. Fortunately, the operation and maintenance of the hydraulic jack is a short set of quite understandable rules, which can be followed by anyone.
- When installing the jack under the load, make sure its base is firmly seated against a level, horizontal surface (floor, ground, asphalt). The surfaces of the stop and the load to be lifted must be parallel.
- The footing should be as strong as possible and must be able to support the entire weight of the load. In cars, this is the stiffener; in private homes, it is the walls with a beam underneath.
- Lift with smooth movements of the pump lever. The load should be stationary, so no passengers should be in the vehicle. When fully lifted, the use of the safety cradle is recommended.
- When the jack is finished and the load can be lowered, check the piston rod for dirt, and if necessary clean it with a rag to prevent corrosion.
- Store and transport the hydraulic jack only in the position indicated by the manufacturer: vertically for bottle and rhombic jacks and horizontally for rolling jacks.
- The pump piston rod, withdrawal screw, and piston rod should be lowered during storage. With regular use of the tool, these elements should be lubricated periodically (as they dry out).
- If partially leaking or evaporating hydraulic oil, top up with identical oil and flush the system (process described above). It is strictly forbidden to pour water, acid and other mixtures! Only low viscosity hydraulic, heating oil or industrial oil.
The rules described above are the main foundations for the confident and continuous operation of the tool. Each jack model has its own unique features and characteristics that each manufacturer specifies in the documentation, which should be read by each owner of these devices.
Hand tools Hydraulic tools Repair and retrofit
Save this page to your social network. Read this page and return to it any time.