The main malfunctions and their elimination
Repair of hydraulic jacks, you can make on your own, with your own hands. You will need a repair kit or purchase of spare parts. The most frequent failure of gaskets and various seals, as a result of which there are oily leaks on the body.
The first point of repair is to drain oil into a prepared container. Reuse is not recommended, it is better to fill with new oil. What to pour in the manual of the jack. Usually suitable common motor or hydraulic oil. It is better to use those that do not react with rubber parts.
The second point of repair we proceed to the disassembly phase. Remove the pistons and examine them for plaque, dirt and rust. If you find dirt and rust, remove it. It is necessary to use special dissolving liquids, gasoline, diesel fuel, white spirit. If you find a deposit and corrosion inside, it is worth getting rid of the oil. There is no need to refill it, the rust did not just appear.
If the pistons are okay, examine the shape of the piston rod. If it’s warped, that’s too bad. It’s probably beyond repair. It is necessary to prevent the bending of the piston rod at the stage of operation not to load the jack with a greater mass than it can lift. Be sure to read the manual so you can use it for as long as possible.
Another malfunction, clogged valves. Often it is enough to simply clean or replace it.
Repairing the hydraulic jack should replace all seals and gaskets. They come in a special kit, sold in specialized stores. The last thing you do is flush and then pour in fresh oil and pump it.
How to rebuild the jack “upside down” or the press with their own hands ?
The jack of “bottle” type, can’t work “upside down”, its design doesn’t provide that, but if you really want you can teach the jack to work in any position you need.
Bottle type jack can not work upside down, its design does not allow for that, but if you really want you can teach jack to work in any position you need.
Pour the oil into the reservoir prepared beforehand by opening the rubber cap (in our case a nipple has been made).
Unscrew the upper packing nut, through which the stem goes.
Unscrew the outer cup, to which is welded a handle to transport the jack.
Find two holes at the bottom. One suction, to the pump, the other bypass, to the tap. We need a suction. It is easy to tell by pumping the pump: the residual oil in the suction hole will be sucked into the pump. Sometimes there is a strainer made of a mesh tube inserted in the suction hole.
To make your jack able to work “upside down” we put a piece of metal or plastic tube such length so that its end is at the top of the working cylinder in the suction port. If there was a filter, it can be put on the end of the tube. In our case it is copper pipe with M6 thread.
Let’s put the jack on its side so the oil refill plug is up and then pour in the oil. And also on the side we start pumping. Pump and deflate. After that we extend the rod to half of its length. Find a suitable tube for the diameter of the fill hole and connect the main cylinder of the jack to the additional reservoir.
Fill the reservoir with oil, turn the jack “upside down”, place an additional reservoir higher than the jack, and begin to push the jack rod back into its place, loosening the screw of the overflow valve at the same time. Oil from the operating cylinder overflows into an additional reservoir.
Next, after the rod has come fully into its place, unscrew and pull out the screw of the bypass valve and look at how the law of hydraulics works, all the air in the main and working cylinders will go out.
After the oil flows through the screw hole of the bypass valve, we tighten the screw back into place and after that the jack works “upside down”, the oil will be sucked through the tube from the lowest point and poured out from above through the bypass hole, so as not to create vacuum the oil walks through the tube from the main cylinder into the additional tank.
Causes of failure and repair of jacks
Naturally, like any technique, the hydraulic jack requires some maintenance, which includes oil refilling and visual inspection. And after a certain time it is flushed and the oil is completely changed and pumped.
Most often the hydraulic jack fail gaskets and seals, for this reason begins to leak oil from the working capacity. In addition, there can be such a malfunction as a jammed rod in its reverse stroke.
At the first oil leak, the jack must be repaired, otherwise the rod can jam later on. To do this, drain the oil, disassemble and replace the packings and seals, then add new fluid and flush.
The piston rod of the tool may be jammed by dirt and debris accumulated in the fluid and passing through the piston rod packing or by corrosion on the internal wall of the jack. To fix a stuck piston rod, the tool should be disassembled and rinsed as soon as possible. If corrosion is found, special treatment of the hoist walls should be performed.
There are other causes of equipment failure that can lead to the jack not working as it should. This is mainly caused by untimely maintenance and improper use of the tool, when the loads indicated in its datasheet are exceeded. All this leads to its failure and, naturally, to repair, which can sometimes be very expensive.
- Stalling of the elevating piston. Could be due to lack of oil or filter clogging. To find out the cause of stoppage, you should disassemble the mechanism, wash it and fill it with fresh fluid.
- The piston does not rise at all. Most likely there is no fluid in the jack‘s reservoir.
- Piston extends slowly or jerkily. There is air in the working compartment of the unit. In this case it is necessary to add oil to the hoist and pump it.
- Insufficient pressure on the piston. Inlet valve must be repaired or replaced.
Virtually all causes of elevator failure can be found and repaired after disassembly. But if the malfunction has been caused by mechanical damage to the jack body or piston, the best option is to write it off and buy a new tool.
Causes of reduced jacking efficiency
Before pumping hydraulic equipment, it is necessary to establish the reasons that caused the deterioration of its functionality. The common factors of disturbance of normal functioning of the mechanism are contamination, as well as ingress of air masses into the cavity of the jack.
Restricted jacking capacity causes corrosion on the surface of the working cylinder.
Frequent reasons for which it is necessary to pump the lifting device:
- high load, which provokes bending of the hydraulic rod;
- formation of air bubbles;
- internal corrosion of the mechanism;
- Poor quality oil, which is filled in the jack, which causes its rapid deterioration.
To eliminate the defects, you should adhere to a number of specific rules. All fasteners are carefully unscrewed, and then the valve, which is responsible for draining the working fluid, is removed. As for the primary piston, it must be removed and carefully inspected for possible damage. The balls on the valves and gaskets should also be inspected, and if their appearance is unsatisfactory, the components should be replaced.
Parts should also be flushed to remove dirt and other foreign matter. Once the mechanism is assembled, fill it with quality oil and begin pumping.
How to change oil in hydraulic bottle jack. How to remove air from hydraulic jack
It is recommended that only special types of oil be used to keep the structure functioning properly. Otherwise it will be difficult to achieve full power while using the hoist.
Extend service life
Breakdown of any tool is often an unpleasant and even dangerous experience that involves loss of time and money. Elevator failure, at the most inopportune moment, can cause unnecessary problems, so it is recommended to pay extra attention when working with this tool. Fortunately, operation and maintenance of a hydraulic jack is a short set of understandable rules that anyone can follow.
- When positioning the jack under the load, make sure its base is firmly seated against a level, horizontal surface (floor, ground, asphalt). Make sure the support and the lifted load are parallel.
- The load resting place should be as strong as possible and should be able to support its full weight. For cars: a stiffener, for private houses: a wall with a beam underneath.
- Lifting is achieved by smooth movements of the pump lever. The load must be stationary, so no passengers should be in the car. Use of the safety cradle is recommended for total lift.
- When the jack is finished and the load can be lowered, check the rod for dirt, and if necessary, clean it with a rag to prevent corrosion.
- Hydraulic jacks should be stored and transported only in the position indicated by the manufacturer: upright for bottle and rhombic jacks and horizontal for rolling jacks.
- The piston rod, draw-off screw and pump piston must be lowered during storage. If the tool is used regularly, these elements should be lubricated periodically (as they dry out).
- In case of partial leakage and evaporation of the working fluid, it is necessary to refill the system with identical oil and pump it (process described above). It is strictly forbidden to pour water, acid or other mixtures! Only low-viscosity hydraulic, heating oil or industrial oils.
The above rules are the basic foundations for the tool’s reliable and continuous operation. All models of jacks have their individual features and characteristics, which each manufacturer indicates in the documentation, which should familiarize each owner of these devices.
Hand Tools Hydraulic Tools Repair and Retrofit
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Proper pumping of the hydraulic jack of the jack and bottle type with their own hands
Jacks are used for lifting, carrying and jacking up heavy loads, such as slabs, machines, cars, columns, etc. Their lifting capacity can be hundreds of tons. Machine design and dimensions vary according to application. High performance and ease of operation make the jacks indispensable in production, vehicle repair shops, the processing industry, power plants, warehouses and other industrial applications. Car enthusiasts can’t do without their own compact elevators either. And the ability to move loads vertically and horizontally is used on construction sites everywhere.
Types of hydraulic jacks
Several types of devices have been created that are convenient for use in different areas:
The bottle jack is the most common and simplest design. It is capable of lifting from two to a hundred tons, has a large support area and a compact body. Therefore, such mechanisms are usually used in the repair of various types of vehicles, especially trucks. Bottle jacks can have a double-rod or single-rod design. Single-stranded, simpler design is used in railroad car service, construction, engineering, pipe-cutting and pipe-bending applications. Two-rod models work vertically and horizontally.
The car jack resembles a carriage that moves under the load to be lifted during operation. Operated by a hand lever and regulated by an oil valve. To open the valve, you must twist the handle of the valve screw. Very convenient for one-way lifting of loads. So it is good for changing a wheel. But it only works on a firm and level surface. There is a transmission version that has a swivel frame.
Hybrid jacks are also called double-acting and are used in auto-repair shops. They are convenient in having a couple of pads for loads. This is actually a combination of the bottle jack and the car jack. Machine is operated by a foot pedal and lever.
The bottle jack is also used at body repair shops. The carriers, connected by hinges, form a rhombus. Hence the name of the mechanism. Very compact device, easy to transport and store.
The carriage jack is good for lifting loads from a low height: sliding machines, railroad rails. The design is based on the bottle scheme.
When the hydraulic jack must be repaired?
Specialists recommend pumping the hydraulic jack periodically. If the device is used frequently, such a procedure is carried out almost every month. Power loss is usually the first sign of trouble.
Preventive maintenance is carried out in the following cases:
- An increase in the concentration of contaminants in the oil. They greatly reduce the effectiveness of the design.
- The equipment is not performing as well as it should.
- Bubbles may form on the surface of the fluid. Air rarely enters the piston, but it does occur.
- Reduced lifting capacity. The specification of the device specifies how much weight the hoist is designed for. Mechanical damage and many other problems reduce the actual lifting capacity.
Assembly diagram for a hydraulic jack
Such problems do not manifest themselves soon in the case, if you follow the rules of operation and avoid mechanical deformation of the housing.
Reasons for the loss of efficiency
Because of its characteristics, the jack is designed to work with fluids that provide high lifting capacities. often than not, it’s about the oil. A special hydraulic version of this fluid is used here.
For the jack to last a long time, you need to keep an eye on the oil level in the jack, the condition of the oil seal and the valves.
This design is generally regarded as one of the most reliable. It is capable of handling a wide variety of weights. Sometimes the lifting capacity of such a jack can reach several dozens of tons. Coefficient of performance is the highest among all representatives of a class of similar equipment.
However, no one is immune to the fact that the hydraulic jack will fail. There may be several reasons for this. The main reason is often the accumulation of large amounts of air bubbles in the. This is detrimental to any hydraulic device. Very often this leads to having to pump the hydraulics. Air bubbles can drastically reduce the efficiency of this type of device.
It is necessary to regularly check the amount of oil in the hydraulic jack system. If its level decreases, it is detrimental to the entire operation of the device. The free space is quickly filled with air bubbles. In this case the operation is sharply impaired. This directly affects the load capacity. There are many methods which allow to eliminate such faults. All of them have the right to exist. The following will discuss several ways in which this can be done. So, we can proceed directly to the instructions.