The use of jacks is effective if you know how to pump the jack. To date, it is impossible to repair the car if there is no jack. This is a special device with which you can lift loads of large mass. A piston having a hydraulic fluid is involved in providing the working force of such a mechanism.
The device and principle of operation of the hydraulic jack.
Applying a jack, make replacement wheels, it allows you to repair the suspension of the car. There are the following types of jacks: retractable (rack) or movable. Vertical extension of rack jacks is carried out in the presence of a cylinder, one or several. The height of the extension of the rack jack can be different.
Rolling hydraulic jack has a different design. The metal case of the device is mounted on four wheels, which are necessary for the movement of the mechanism. A hydraulic cylinder having a lifting mechanism is reinforced in its holes. The raising of the platform is made due to the presence of a special cylinder, which is advanced horizontally.
What elements include the device of hydraulic jacks
Table of characteristics of jacks.
The lever of the device provides actuation of the pump, pumping hydraulic fluid into the cylinder through a special valve. Hydraulic or working fluid is an oil that is squeezed out in a cylinder. The jack drops back with the valve open, located on the pump, so that hydraulic fluid flows into it.
It is easy to use hydraulic jacks. They should be located on a flat surface of the ground under the car. After closing the valve of the device, its lever is pressed until the car is raised to the required height from the surface.
To lower the car back to the ground, when the wheel is already replaced, the valve opens smoothly counterclockwise. When the device is in the original position, the valve is closed back, turning it in the opposite direction.Back to table of contents
How to pump jack
The principle of the screw jack.
For the jack, as well as any mechanism, periodic inspection and maintenance is necessary. Fluid can be poured into the cylinder, since the use of the device is associated with oil leakage through seals, as well as oil seals. Using a car jack to repair the car, apply an insurance stand. By adjusting the device with it, you can prevent the car from falling to the ground if the jack is faulty.
Storing the device in places where there is high humidity leads to rust at the cylinder. For the same reason, the working cylinder is able to become unusable. However, the lack of a hydraulic jack is a slow work speed and a small lifting height. Some models have a large enough own weight, so it’s not very convenient to transport in the trunk.Back to table of contents
Instructions for proper pumping device jack
The scheme of filling the hydraulic jack with oil.
Among the advantages of jacks emit a rigid structure, as well as the height of the lifting of the load from the ground, the greatest capacity with smoothness, the pickup height is minimal. All these advantages give high efficiency.
The reasons for the failure of the equipment can be any. For example, prolonged use of the device can cause air to accumulate in the form of bubbles. This reduces the efficiency of the use of the jack, that is, its effectiveness drops sharply. This is due to the ingress of air into the hydraulic mechanism due to lack of hydraulic fluid.Back to table of contents
Pumping and troubleshooting jack
Lead the device to its original state will allow the following actions:
- Begin pumping should be, if the valve is open by-pass with the cork of the oil tank.
- Pump the pump of the device a certain number of times, which will allow to displace all the accumulated air from the working cavity into a special container for liquid.
- Carry out the closure of the oil reservoir port and the overflow valve.
With the correct implementation of all the work and air removal device should work in proper mode.
Otherwise, the above actions, according to the instructions, are repeated.Back to table of contents
How to properly jack the other algorithm
Corroded parts are recommended to be replaced.
Since the above method of pumping the jack is not the only one, you can gradually perform the following steps:
- With a slow lifting of the load with a jack or its complete malfunction, the presence of air in the device cavity is determined.
- The locking needle should not be turned back 1.5-2 turns, and the plunger of the jack is raised by the screw to the top point, which is the extreme, and then it is lowered again to return to the bottom position.
The last operation is repeated 2-3 times. In order to prevent the occurrence of this problem, you should periodically check the level of fluid in the jack. If it is not enough, be sure to add oil.
The pumping of the jack is repeated after the ingress of dirt into the working cavity. To remove contamination, the head of the case is turned off, then kerosene is poured into its base. Next, pump the jack, after unloading the shut-off needle. After completing the operation, kerosene is removed, and the working cavity is filled with pure hydraulic fluid.
In general, the algorithm is as follows:
- Oil is poured, then close the box.
- The piston should be pumped by raising it to failure.
- The plug is unscrewed and pressed on the piston, releasing air from the cylinder.
- Add oil, closing the stopper, etc.
This is done until all the air is out, and the output of the hydraulic oil will be in accordance with the bleeding of the brakes.
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DIY jack repair
Diagram of the hydraulic jack.
It is difficult for a hydraulic jack to find a replacement in order to lift and hold equipment. There are different signs that indicate the failure of the equipment. For example, lifting cargo is difficult, and the level of lifting to a height can be significantly reduced.
It is possible that a large number of moves should be made to install the device at the required height. If the hydraulic jack does not fall down, then this is a clear sign of its failure. The decision on the choice of the method of pumping will help the knowledge of some damage. This includes:
- The presence of rust inside the device, limiting the process of lowering the mechanism to the desired position.
- Extreme load, tested by the device, which leads to bending of the rod.
After disassembling the unit, it can be seen that the device has a cylinder containing a piston or rod, which is moved inside it in the presence of working oil. The pressure on the fluid is created during the operation of the cylinder valve. There is a pump that directs fluid to the cylinder.
The device lowers the load at a speed that is adjustable when there is a hole. It is necessary for the flow of incoming fluid from the cylinder. In the jack there is a thread on the rods, cases and bases.Back to table of contents
Jack disassembly activities
Jack repair scheme.
To open the unit perform the following basic steps:
- Disassemble the unit completely using keys.
- Turn off fasteners.
- Remove the valve from the device, which bleeds the oil, as well as the primary piston.
- Carry out a detailed inspection of the unit to check the quality of the ball of the special valve and gaskets to replace them.
- Clean the device from unnecessary elements and wash the system.
- After opening the unit, an oil change is made.
This should be a spindle oil with a high grade or type Total LHM +. Next, make the installation of other gum and drain the used oil.
To completely drain the lifting part of the device is moved down and then up. Open chambers allow the release of all piston fluid. The device pressure spring must be removed. Next, close the valve by bleeding the oil using a ball. For exact oil ingress into the device, it is required to lift the jack up and then lower it down. In the completion of the work carried out the installation of fasteners: pins and studs.
The device is equipped with two valves - pressure fittings. Each of them has a spring-loaded "plug", which is a stud with a cap. Its point should enter into a hole of small size, and the cap will rest against a special spring.
Scheme park hydraulic jack.
The first valve is usually opened under pressure from the lever, it is unscrewed for lowering. The oil is launched into a large “holding” cylinder after it has passed through a small “swinging” cylinder. When the pressure from the lever drops, the valve begins to hold the oil while being closed. The second valve is necessary for etching into the tank from a large "holding" cylinder in conditions of excess load.
Before lifting the jack adjust to a certain weight of the load, so that it could not burst during pumping, otherwise some parts can simply fly out of the mechanism housing. Therefore, pumping the jack requires compliance with safety measures.
Both valves are pre-disassembled to check where the spring with the “nail” is, whether they have the correct position. Disassemble the device, bed any material or newspaper. Make sure that not a single trifle can fly out of her seat and get lost, since it will be very difficult to find a replacement part later.
In case of malfunctions after pumping a jack, it is required to fill in oil through any of the valves, it is possible through the first one. The jack's paw must be slowly raised by hand, and the nozzle is pointing upwards so that the air can escape during the descent, but not completely. This may cause a rubber stopper that has a large rivet shape on the surface of the cylinder.
When disassembling the second valve, it is reset again, taking into account the correct weight. Twist much is not necessary, since the descent of air occurs under load. Carrying out a gradual twisting, lift the weight of a given weight. After that, pumping stops. Then check the possibility of descent in case of excess weight.Back to table of contents
How to pump a rolling Chinese jack
If the life of the Chinese rolling jack has come to an end, that is, it can no longer hold the car, then the device can be pumped. This will allow not to spend extra money on new devices. When carrying out work it is necessary to observe safety precautions.
To this end, pull out two cotter pins that serve to lock the lever axis, and remove the lever. When the oil is flowing through the piston, the part is gently pulled out so that the liquid does not hit the face. Then inspect the inside of the device. If the sealing gasket has fallen into disrepair, this is due to the ingress of dirt. If there is no new gasket, then you can flip the old one.
It is required to fill in oil in a piston opening, smoothly having lifted a hand a jack. Removing the spring will facilitate the entire procedure. Oil is poured when the top point is reached. It is pushed by the piston until its stroke becomes tight. In the absence of an anther in a jack, they put it on to avoid getting dirt in the cylinder. You can use silicone grease when pumping. At the end fasten the locking wire.
The rolling jack will work according to the following principle:
- The piston lever will be held in tension by the blocking wire.
- The boot will be clamped between the lever and the cylinder.
As a result, this will help to avoid contamination of the cylinder, which will increase the service life of the mechanism. Maximum lifting device will allow you to save face from getting grease from the cylinder.