How to unscrew a broken bolt from the engine block or other sites: available ways
In the process of repair and maintenance of the car, as well as any other equipment, there is often an urgent need to remove individual elements of the internal combustion engine or chassis, body panels, etc.. d. At the same time removal of components of the engine, Attachments and suspensions are often the most problematic operation. The reason is, that the nodes can be tightened with bolts or pins, moreover, the torque is quite large.
If you add to this the temperature differences in the hood space, oiling, accumulation of dust, dirt and other deposits, it becomes clear, that unscrewing various bolts and other fasteners is not only responsible and time consuming, but also often a difficult task. In this article we will talk about that, what can be done, if the pin or bolt is broken, as well as how to unscrew a broken bolt.
Torn bolt thread, the hairpin broke or the bolt in the engine block broke: how to unscrew
so, bolts and pins often "ferment", covered with rust, can be dragged or twisted with a skew (not on the thread) during previous operations. This is true for all models and brands of cars without exception.
In any case, a common situation is this, when the master broke the thread while unscrewing the bolt, broke the hairpin, broke the head of the bolt, etc.. d. A situation is also possible, when the tightening torque when twisting is greatly exceeded, the bolt bursts, remaining untwisted. Naturally, the remains of the bolt must be unscrewed, then the pin or bolt should be replaced.
Usually, bolts break in cases, when the bolt has rusted or stuck, at the same time at unscrewing too big efforts are added. This usually affects cars with mileage or cars, which are operated in difficult conditions. Most often, threaded connections begin to cause problems as a result of contact with moisture. For the chassis of the car, such contact is inevitable. In the case of the engine, The cylinder head is screwed to the cylinder block, the tightening torque is large.
Anyhow, the most problematic situation is that, that the bolt may be broken level, that is, it is not possible to unscrew it in the usual way or with the help of simple tools. In other words, The "body" of the bolt does not protrude above the surface. In this case, there are several ways to solve the problem, the most common are:
- bolt drilling;
- unscrewing the screw by welding;
First of all, the choice of one or another method depends on certain conditions. If the bolt scrolled before breakage, then the main task is to "attach" to his body, to then unscrew the remnants. If it is impossible to turn the bolt, then it is necessary to carefully drill the remains of the body in the hole. Let's look at the available methods in more detail.
Let's start with that, what you need to know for a successful outcome, how to unscrew a broken bolt, as well as perform a number of additional works before unscrewing.
- At the initial stage it is necessary to remove dirt, oil residues, rust, etc.. d. from the problem area. Also, be sure to apply a special tool to the threaded connection, to bolts "deoxidized". Such liquid can be special cleaners. These are warehouses, removes and softens rust, dirt, etc.. d. WD-40 or pure oil is quite suitable for these purposes.
- Let's move on. If the fragment protrudes above the threaded hole, it is also possible to make several hammer blows through it, the bolt is additionally heated (example, using a blowtorch). The only thing, it is possible to strike on a bolt or to heat it only in that case, if other parts are guaranteed not to be affected by such exposure, elements or a threaded hole.
If you managed to break the thread (the bolt is spinning), then the broken screw is unscrewed with pliers, adjustable wrench, etc.. d. You can still chisel, to make a "groove" on a bolt body on a metal hacksaw or a Bulgarian, then you can try to unscrew the fragment with an ordinary screwdriver.
Also in the wreckage, if the body protrudes high enough, a transverse through hole is drilled, in which the metal rod is inserted, nail, screwdriver, etc.. d. Then the lever allows you to unscrew the fragment with the help of handy tools.
- Often the body of the bolt does not protrude much above the surface, that is, the bolt is broken almost level. This complicates the process of removing debris from the threaded hole. In this case, welding helps well. To implement tasks, it is necessary to pick up a bolt with a hat similar in diameter, then you need to weld it with a welding machine to the body of the fragment in the threaded hole.
Then you can try to unscrew the fragment with a wrench. It is important to remember, that the weld may be brittle at the joint, so you shouldn't make too much effort. Let's add, that in addition to welding, special types of glue are sometimes used for such cases. However, this method is not widespread, as these types of glue are not always at hand, as well as some doubts about the reliability of fixation by such means.
- The most difficult case is considered to be a broken bolt, which broke off, example, level with the surface or even lower. This is often the case, when the bolt in the engine block breaks off. In this case, the methods described above do not always work. To solve the problem, you need to know, how to unscrew the wreckage from the hole, drill a bolt from the car engine unit, etc.. P.
We also recommend reading the article about it, how to tighten the bolts of the cylinder head. In this article you will learn about it, how to tighten the cylinder head, with what effort and in what order the upholstery of the block head is carried out.
First of all, it is necessary to prepare a drill and a set with thin drills. pay attention, it is not recommended to perform such work without certain skills. The main task is to drill a few small holes in the body of the bolt. This is done so, so that it is now possible to combine these small holes into one large one. Then a screwdriver is inserted into the hole, after which the fragments are unscrewed.
A more complicated way is to cut the left thread in the body of the broken bolt. In this case, you need a drill and a tap. First, a hole is drilled in the body of the fragment, then the left thread is cut with a tap. Then another bolt is screwed into this thread. After, as such the bolt will be screwed in all the way, the fragment must begin to unscrew from the hole.
The last available way to remove a bolt fragment, which broke in the threaded hole, is considered drilling. The method is quite complicated, requires special skills. The main purpose is not to damage the thread of the hole when reaming the fragment.
To drill a fragment, first a hole is made in its center with a thin drill. Then the drill changes to thicker, etc.. d. After, as the walls of the body of the broken bolt become as thin as possible, you need to try to break them with metal wire or tweezers. The debris is then removed from the hole. This method in the case of proper implementation eliminates the need to cut a new thread in the hole or restore the existing one.
Let's summarize
As you can see, there are several ways to unscrew a broken bolt or pin. In each case, it is necessary to take into account the nature of the body breakage, the location of the fragment itself, possibility of access to the problem area, possible consequences of heating the remains of the bolt, etc.. d.
Finally, note, that before unscrewing the bolts it is desirable to carry out treatment before the procedure to remove dirt and soften rust. In this case, if different standard methods of unscrewing do not give the desired result (the bolt does not go), then it is optimal not to make much effort, so as not to break the hairpin.
The same can be said about tightening pins or bolts. The point is, that it is necessary to tighten fastenings with strictly certain effort and in the specified order (example, cylinder head fitting). Ignoring this rule leads to that, that the studs or bolts break, are extracted, deformed, etc.. P.
We also recommend reading the article about it, how to unscrew the oil filter without a key. In this article you will learn about the available ways to unscrew the oil filter without a puller.
In case of such problems it is better to turn to experienced professionals, which in many cases will unscrew the problematic broken or sour bolt. If you avoid breaking the bolt is not possible, then qualified craftsmen will remove the residue from the hole with minimal risk, and, if necessary, restore the damaged thread.
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