Rolling jacks are characterized by ease of use, impressive carrying capacity, have a smooth rise and stroke. Ideal for use as car lifts both at specialized service stations and in personal garages. Moreover, many car owners manage to make such an assistant on their own in order to use all its advantages for less money. Today we will consider the probable malfunctions of the rolling jack type jacks, and we will figure out how to fix them with our own hands.
Possible breakdowns and their causes
Hydraulic jacks rarely rarely lose their functionality thoroughly, mainly a problem in valves, lack of working fluid (oil) or contamination. Nevertheless, any device in the stage of its operation can fail.
Before proceeding directly to the issues of repair work, it is necessary to determine the likely breakdowns and factors that can provoke them.
So, among the frequently encountered the following malfunctions:
- the absolute loss by the device of operability , which is expressed in the fact that there is no way to raise or lower the main piston (working rod);
- improper work (as a rule, wedges a little) during the lifting process;
- spontaneous lowering of the device under load;
- the drip jack is a partial or complete leakage of the working fluid (oil).
To repair the jack you will need certain tools and materials:
- reservoir for receiving drained oil;
- specialized washing liquid (kerosene or gasoline is allowed);
- working fluid - oil.
Before repair work, you can buy a repair kit for a rolling jack in advance. Typically, piston and plunger seals are included.
How to fix the jack?
Of course, you can repair the rolling jack yourself. Only for this you will need to purchase a repair kit or individual spare parts, based on what specifically broke. As a rule, various gaskets become unusable, as a result of which the working fluid begins to leak out. Repair requires a suitable repair kit.
Under any circumstances, it is necessary to disassemble the structure and drain the working fluid from it . This must be done carefully, and the working fluid should be drained into a previously prepared container.
It is hardly suitable for secondary use, it is advisable to replace it with a new one.
You will find the brand of oil in the manual for the device. Nevertheless, in the bulk the usual motor oil (for example, grade 5W-40) or hydraulic fluid for hydraulic systems is suitable. It does not destroy rubber, does not harm the surface of the working piston, has medium density and is safe for humans.
There are specialized repair kits - hydraulic jack repair kits - for any individual modification of the rolling device. They already include all suitable rubber gaskets and all kinds of consumable spare parts (based on a specific modification). Try not to purchase too inexpensive and expensive products, it will be optimal to buy goods from the middle price category.
After that, it is necessary to disassemble and pull out the pistons and inspect their surface for rust. If corrosion or contamination is detected, they must be thoroughly disposed of. Along with pollution and corrosion, waste oil is also disposed of. You can use specialized cleaners (diesel, gasoline, white spirit, solvents, etc.) for this.
Be sure to inspect the stem configuration. In the event that it is bent, then, apparently, it is unsuitable for reconstruction. In such a situation, you need to either purchase a new piston (which can become a snag, since there are practically no such basic components available), or buy a new mechanism for lifting. Therefore, it should not be brought up to the point where the stem is bent. As a rule, this happens due to a significant excess of the permissible weight of the car, which was lifted by means of a hydraulic jack.
Similarly, a common cause of breakdown of the rolling hoist is the contamination of its internal operating valves.
They are included in the structure of the system for moving the working piston of the device (raising and lowering it). Check oil transfer valves. Close attention must be paid to how tightly they sit in the landing nests. If the contact is loose, check the springs, which are probably loose. If the valves are worked out, wrinkled, then they need to be replaced with new ones. At the same time, they can simply become clogged, and the ball-valve begins to loosen in its place. This is the source of fluid flow.
When replacing the working fluid in a rolling hydraulic jack (and this must be done with a major overhaul), it is mandatory to pump its hydraulic system. Based on the fact that the structure of various lifting mechanisms is different, it is impossible to give a universal answer to the question of how to pump a hydraulic jack. Without highlighting details, the procedure will be as follows.
First of all, you should unscrew the plug from the neck to fill the hydraulic jack with a working fluid (or to drain it, it depends on the structure of the jack).
Then completely drain the used oil (into a previously prepared tank). Next, fill in the cleaning agent in the system to remove everything that remains of the spent working fluid and dirt, which, presumably, is present inside (use non-hazardous compounds for rubber seals). Subsequent events are carried out in the following order:
- pour a small amount of fluid into the system;
- work with a lever so that the liquid substance disperses throughout the system;
- add more and do the operation again;
- topping up until the stock reaches the extreme top position;
- open the stopcock to allow the working piston to return to its initial lower position;
- as it moves, the cleaning fluid will be expelled from the device through the drain hole;
- if the liquid is highly contaminated, then the operation should be done several times in a row until it becomes somewhat clean.
After cleaning the system, you can begin to fill in fresh oil. The steps will be similar to those performed with the cleaning fluid. After that, all the covers must be closed and wiped the oil that has got on the hydraulic jack body.
Constantly watch the level of working fluid in the device. Over time, rubber gaskets lose their quality and let the oil out. In its place, air enters the hydraulic system, and its airing occurs. This can become a circumstance that the piston will no longer reach its upper location, because air can be compressed in contrast to the oil. If you notice a similar problem, add or replace the working fluid in the hydraulic jack, and also change the rubber gaskets.
Repairing a two-ton or three-ton rolling jack is no different at all — except with the amount of oil needed to fill it.
After the elimination of all malfunctions is completed and fresh oil is poured, the hydraulic jack is “pumped” - they let out excess air. For this purpose, they first “energetically” work “with a plunger until pressure is formed. Then air is vented through specialized plugs and oil is added.
After completion of work, it is recommended that the hydraulic jack be relieved of loads. Keep the device in a dry and warm place. Due to the penetration of excess moisture, the mechanism is able to become corroded, and the cold will adversely affect the quality characteristics of the working fluid. It is advisable not to use the jack in hard frost . The loads on the lifting gear must not exceed those for which it is designed.
With continuous operation, the replacement of the working fluid (pumping) should be done once every 2-3 months. Then, in order to maintain the hydraulic jack in working condition during the period of “downtime”, there is no need without changing the oil in it - 2-3 working movements of the rod once every 3 months are absolutely enough.
Summarize. In case of failure of the hydraulic jack, it is necessary to check 3 components:
- quantity and quality of oil;
- the presence of air bubbles in the system;
- how tight the valves sit in the seats, pollution.
In the vast majority of situations, to solve all the difficulties with the jack, it is only necessary to clean and change the working fluid.
See how to repair a rolling jack in 10 minutes.