Anyone who is dealing with car repairs, whether it’s an ordinary car owner or a professional car repairman, knows how indispensable a hydraulic jack can be. It helps to raise the body of the car to a relatively small height and keep it in this position for sufficient time to simply replace the wheel, and make complex repairs to the chassis and internal mechanisms, providing access to them from below.
Scheme park hydraulic jack.
At the same time, the hydraulic jack is characterized by a number of advantages that distinguish it favorably from the mechanical counterpart. First of all, it is high efficiency, reaching up to 80%, smooth operation and precise braking.
Depending on the model of the jack, the lifting capacity can reach 200 tons, and the load itself is stable and rigid. That is why it is preferred to use car service workers as a mobile hoist. And although the device of hydraulic jacks seems to be quite complicated, in the event of a breakdown, it is quite possible to repair them with your own hands.
The main causes and types of faults hydraulic jacks
According to the principle of operation, any hydraulic jack is one, however, in terms of design, they are single-plunger and double plunger, and by the type of inclusion they are manual or equipped with electric drive. If it is used extensively, as is usually the case in an auto repair shop, the main causes of failure in work are either overload during lifting or for some reason the hydraulic system refuses to work.
Vertical hydraulic jack.
In the first case, the deformation of the thrust rod occurs, as a result of which it bends and loses the possibility of passage through the clutch, which is why it is wedged in it. Then the repair of the hydraulic jack will be to replace the rod, because it is made from a special steel grade, and it is not enough to even out it in an artisanal way.
The failure of hydraulics, in turn, may be due to several reasons. Engine oil is used as a working fluid for a hydraulic jack. Store and transport it can only be in an upright position, which is far from always, and then the oil begins to flow. In its place air begins to penetrate, which gradually slows down the work of the lift until it stops completely.
In addition, the internal surfaces of the components of the hydraulic system of the jack can eventually rust, and rust inhibits the free running of the entire device. Gaskets or a ball can wear off in the bleed valve and on the primary piston, which disrupts the normal movement of oil in the system. Repairing the jack and eliminating such faults is quite possible on their own.
Back to table of contents
DIY hydraulic jack troubleshooting
To repair the jack, it is necessary to identify the specific cause of the malfunction, and for this it needs to be disassembled into its component parts.
The principle of operation of the hydraulic rolling jack.
Its design consists of a housing, a piston and a working fluid, that is, oil. All elements are fastened together with the help of threaded connections of various kinds, therefore for disassembling the jack you will need to use a whole set of wrenches, including adjustable wrenches. After all the connections of the hydraulic jack are untwisted, it is necessary first of all to drain the oil from the internal cavities into the prepared container. The pistons and oil drain valve are then removed for thorough inspection.
Pistons are cleaned of accumulated rust, the supporting rod is checked for bending. Then the quality of all gaskets and valve is checked. If they are deformed, they will have to be replaced with new ones. Usually, the throughput oil valve simply becomes clogged with dirt, and the ball stops sitting tightly in its socket, letting in oil.
Gaskets and sealing rings are desirable to replace everything, because their deformation is often invisible with the simple eye and appears only under high pressure. After that, the entire interior of the system must be washed several times with a special washing liquid.
Then the whole structure is assembled again, and the repair of the hydraulic jack is basically over. It remains to fill in its interior with fresh oil. Before this, the jack must be thoroughly pumped so that no air bubbles remain in the system. The design provides a special neck with a screw cap, through which the oil is poured.
Changing the oil for jacks with your own hands occurs without the use of additional tools, but you need to take oil specially designed for use in industrial equipment. It must fill the entire interior of the jack, reaching a special mark. After that, you can use it again for its intended purpose.