How to unscrew a broken bolt in a hard-to-reach place. How to unscrew a broken bolt correctly? How can I unscrew a broken bolt?

Sometimes during the repair process you encounter bolts that are so old and “stuck” that if you try to unscrew them, they will simply break. Accordingly, the question immediately arises of how to unscrew the remaining rod so as not to damage the parts connected by it.

A novice master may be frightened by such a seemingly hopeless situation, but there is no need to be afraid: unscrewing a broken bolt is not so difficult.

To begin with, you should remember that if the bolt is tight and does not want to be unscrewed, then you do not need to force it. It is better to immediately fill it with anti-corrosion liquid, for example, WD-40. Then tap the head well with a hammer so that the liquid can penetrate deep into the thread. After a couple of minutes, it will be several times easier to remove the stuck bolt.

Even if you have already broken off the head, fill the bolt shaft with “Vedashka” or penetrating lubricant - this will make the process of removing it easier.

There are two types of bolt fractures: when the head breaks off after the bolt has had time to move out of the seat a little, or when the remaining part is below the surface.

When the fault was above the surface

In this case, it is easier to deal with the bolt. Here are some of your options:

Grab the rod visible above the surface with pliers or pliers and try to unscrew it.
Take a punch and set it at an angle to the edge of the bolt. Try to give the bolt a rotational movement by lightly hitting the center punch with a hammer. Sometimes such small efforts are enough for the rod to begin to unscrew.
Using a hacksaw for metal, cut a transverse hole for a flat screwdriver on the visible surface and try to unscrew it. You can also use a grinder or even a chisel for this.
Another option is to use welding or aggressive glue. Try welding/gluing another bolt to the rod and unscrewing it. You can also weld, for example, an L-shaped hexagon or any other suitable handle that can be used as a stop.

If you are using welding, do not try to unscrew a heated bolt right away - let it cool. Remember: metal expands when heated, so it will be impossible to remove a heated bolt. Water the welding area cold water to speed up the cooling process.

If the bolt breaks below the surface

For the first method, you will need a drill with a very thin drill bit. Using a drill, you need to drill three holes on the same plane, and then connect them in one line. This will create a hole for the screwdriver - now you just need to insert it into homemade groove and unscrew.
The second method is more complex and time-consuming. It requires a drill, a tap and patience. Using a drill, you need to drill a hole in the center of the stuck bolt. Then, using a tap, carefully cut a left-hand thread in this hole. You will be installing a left-hand thread screw into this new thread. After the screw is completely tightened, the old bolt will begin to unscrew.
The rod can also be removed by drilling. This is the most time consuming and dangerous method, as there is a risk of damage to the thread. For drilling, use a drill with thin drill bits. To drill a hole in a bolt high class strength, it is better to use a cobalt or pobedit drill.

Use a thin drill to drill a hole in the center. It is very important to drill the first hole exactly in the center so that there are no distortions when further work! The drill cannot be overheated, so you need to drill at low speeds and constantly cool it in water or oil.

After this, a thicker drill is taken, then the next one, and the whole process is repeated until practically nothing remains of the frame. You can drive a special extractor with a reverse thread into the resulting hole and unscrew the remaining rod. If you don’t have an extractor at hand, then you need to drill out the inside as much as possible. And when the walls become thin enough, try to break them using tweezers or sharpened wire. Be very careful when performing this procedure so as not to strip the threads.

If it was not possible not to touch the thread, then you will have to cut a new one, and the new thread will be larger than the previous one. If the diameter of the previous bolt thread was M10, then the new thread will have a minimum diameter of M12.

Repairing a car is far from the easiest process, and it doesn’t matter what brand the car is or what year it is made. All cars are subjected to serious loads every day, which means breakdowns are inevitable. The average motorist can easily fix most of these faults in a garage, working slowly and carefully. If you are careless when it comes to car repairs, you can often complicate the situation.

It so happens that in the process repair work When tightening or unscrewing bolts and studs, the threads break off. This is very unpleasant, especially if there is no knowledge of how to unscrew a broken pin. This situation confuses any repair. Let's try to figure out how to get out of this unpleasant situation.

Often fasteners break if the craftsman is large and has great physical strength, and the pin is stuck or rusted to the thread. It's about not about those cars that have just rolled off the production lines. Very often, owners of old cars that were stored and operated carelessly face similar problems. And to be even more specific, most likely such a machine was stored in places with increased level humidity. Chassis parts - studs - are almost constantly in contact with water. Therefore, it is not surprising that these elements rust. As a result, the owner is wondering how to unscrew the broken stud from the hub.

However, the fasteners do not unscrew and break not only due to moisture, but also due to high temperatures. For example, the exhaust manifold can be heated up to 400 degrees. As a result of exposure to high temperatures over a long period of time, the stud corrodes.

How do studs break?

These fasteners can break in different ways. Most unpleasant situation when they are literally cut flush. Then the master has to think about how to unscrew the broken pin, because without using special tool And technology is indispensable in this case.

It is much better if the part breaks already at the exit from the thread, when a small part of its “body” will be visible and remain on the surface. In this case, if the bolt has already been torn off, it will turn out and can be manipulated with pliers, screwdrivers and welding.

Effective ways to deal with broken bolts and studs

Professional locksmiths know several effective methods How to unscrew a broken pin. Before you start this task, you need to prepare. By these works we mean cleaning the surface from dirt and grease. It is recommended to pre-treat the threaded connection with WD-40 or ordinary machine oil. You can also ease the situation by hitting the piece of wood with a hammer several times. Often the problem is solved by heating - the pin or bolt, provided that it looks out of the hole, is heated with a soldering iron. Then it can be removed relatively easily.

How to unscrew a stud if it breaks above the thread

If in the process it was possible to break the thread even a little, that is, if fastener started to turn out, you can try using pliers or pliers. A good and powerful one will also help in this difficult task. In the second option, you may also need a grinder. Sometimes a chisel will do just fine - the main thing is not to use excessive force. How to unscrew a broken wheel stud this way? Make a transverse hole for a screwdriver and unscrew the pin with this tool.

If a screwdriver does not help, then you can use this operation. This operation is quite easy. Prepare a bolt whose head approximately corresponds to the diameter of the stud. Next, the bolt is welded to the fragment protruding from the hole. Then, using the key and without extra effort They try to unscrew the unfortunate pin. Experienced auto mechanics say that there are special adhesives with aggressive action, which can be used as cold welding. But they are not always effective.

If the pin breaks below the surface or in the hole

In this situation, you will need a drill, a thin drill bit for it, as well as good tool skills. Before unscrewing the broken pin from the engine block, it is necessary to drill 2-3 or more thin holes in the body of the pin. Then these holes will have to connect into one single hole. They insert a screwdriver here and try to unscrew the broken pieces of the bolt.

Left-hand thread in stud

The second method is more complicated. It is used when it is impossible to unscrew a broken pin using any of the available ways. In this case, the measures taken will be even more drastic. This method will require an electric drill, a tap and a lot of time. First of all, a hole is drilled in the stud - right in the center. Then carefully cut the thread in the hole with a tap.

Note important point: before unscrewing the broken pin from the head, make sure that the thread is “left-handed”. When a new bolt with the same thread is screwed into the newly cut part, the moment it reaches the end, the broken pin will begin to turn out.

Drilling

And finally, the third and most radical way. It is used to remove broken bolts and studs from the hole. This is drilling. The method is very difficult. It is much more complex than all of the above and is the most dangerous. There is a risk of damaging the threads in the bore of the engine block or cylinder head. You should hold the drill securely, as if you do this, there is a serious risk of damaging an expensive part. The stud is often made of harder grades of steel, and the head is made of aluminum. The commutator body is cast iron, so it is also softer than a steel stud. The drill will definitely go from a solid stud to a more soft metal. This happens especially often if the work is carried out in a confined space and the drill is installed at a slight angle. The principle of drilling is as follows: you need to make a hole strictly in the center of the stud with a thin drill, having previously cored it, then install a thicker one in the drill and repeat the entire procedure.

The main thing here is to drill strictly in the center. When practically nothing remains of the stud body, the wall will become thin. It can be broken. You should very carefully break off the remaining pins using pre-sharpened wire or tweezers. It must be remembered that any action is carried out as slowly and carefully as possible. If you act rashly, you will need to think not about how to unscrew the broken block stud, but also about how to restore the cylinder head itself. And these are significant costs.

We use a conductor

You can greatly simplify the operation of drilling out broken studs. This is relevant for those who often repair engines. A simple conductor will help the master. The dimensions of the part are taken from real engines. On the conductor, and this metal plate, the same holes are drilled in the same places as on the head, as well as on the manifold. Holes for bushings are also made in the jig. They will keep the part from moving on the block.

With the help of such devices, you can greatly facilitate the task and figure out how to unscrew a broken pin from the exhaust manifold by drilling without damaging the manifold itself.

Extractors

An extractor is a special device that allows you to remove the remains of faulty fasteners or unscrew a broken pin. The device is very simple and at the same time ingenious. In order to remove a stuck or broken part, you need to somehow hook it and then unscrew it. And all this is done very simply. You need to drill a hole in the center of the stud, wedge some tool in the shape of a cone or cylinder into it, then use this tool to remove the bolt. This is the extractor. These devices make it much easier to resolve issues such as unscrewing a broken pin from a manifold or from any other places.

There are several types of extractors:

Wedge-shaped.
Rod.
Spiral.
Screw.

Now these devices can be purchased in sets, but they are also available for sale individually. Experts recommend using these tools. They make solving difficult situations such as broken bolts much easier.

Choosing steel for the stud

Often auto mechanics make their own studs. They recommend making these fasteners from the following grades of steel: 35, 40, 45, 50, 55, 60. If you make a new fastener from this metal, the result will be a product with sufficient tensile strength.

If the studs will be purchased in stores, you should not choose the cheapest ones or those that you saw on the counter of a car store. The most reliable products have a part number - 13517010. The penultimate number indicates that this stud has sufficient tensile strength.

Before screwing in the stud...

So that you don’t have to think about how to unscrew a broken pin, before getting to work, it is recommended to lubricate the part with graphite, or better yet, let it better element unscrew together with the nut, which will cause it to break. And finally, it is also better to treat the nut threads with graphite lubricant. In the future, this will prevent the part from breaking or breaking.

Very often an old bolt that for a long time did not unscrew, almost “tightly” sticks to the thread. If you apply excessive force when unscrewing such a bolt, it may simply break. A rather complicated situation arises that can confuse even experienced craftsman. How to get a broken bolt if there is nothing to grab it with?

First, you should fill the broken bolt with some kind of lubricant, and, if necessary, a rust dissolving agent. After this, the bolt is tapped several times well with a small hammer so that the liquids penetrate deeper into the surface better. threaded connection. Such simple processing will make removing the bolt much easier.

So, a broken bolt cannot be grasped by any tool if it breaks below the surface or flush with it. In such a situation, you can drill a small slot for a screwdriver. For this you only need small size drill.

Using such a drill, a series of holes are made, and then the partitions between them are broken out. The result is a groove where a screwdriver is inserted and the bolt is unscrewed with its help. At the same time, there is strong pressure on the screwdriver from above. And to make it easier to unscrew the bolt, the screwdriver can be clamped with a key.

If this method is not suitable, you can glue it with aggressive glue based on strong acids or weld it to a broken bolt metal rod, handle or other bolt. This will make it quite easy to unscrew, but it is not always possible to glue something to it with sufficient reliability, and welding may not be available, so this method not used too often.

The third method is to first drill a hole in the bolt, then make a thread inside it (reverse orientation), and then screw another bolt inside. The other bolt will be slightly smaller, but that doesn't matter. The most important thing is that now you can easily unscrew both bolts.

And the last thing you can do if all else fails is to completely drill out the bolt. To do this, use several drills. They start drilling the bolt with a fairly thin drill, but gradually move on to an increasingly larger one.

As a result, the walls of the bolt will become thin and they will simply break. It is not a problem to remove pieces of a broken bolt using tweezers.

This method of coping with the task always works. But there is one subtlety that should be kept in mind all the time. A broken bolt must be drilled strictly in the center.

If the hole is offset from the center, then by the time the bolt is almost drilled out, the thread will be damaged on one side, and on the other side there will still be a rather thick wall that is not so easy to break. If you drill the bolt strictly in the center, such a problem, of course, will not arise.

Personally, I have repeatedly encountered the problem when a bolt or stud breaks at the root. Moreover, I am not some kind of auto mechanic or mechanic. I say all this to mean that this quite happens with an ordinary person, who periodically deals with technology or other technical parts.
Well, since you find yourself in such a situation, then don’t despair - everything can be fixed. I offer you seven ways to get out of this situation and free the thread from a broken pin or bolt.

Preparation before turning out the fragment

But don’t rush to start unscrewing right away. Before doing this, you need to take steps that will make your efforts easier.
First of all, spray the broken area with penetrating lubricant. This can be any “liquid key”, WD-40. Let's wait a little.

Method 1: Flat head screwdriver and hammer

This is the easiest way, but it is not always suitable. In about half the cases, the pin breaks off with a fragment sticking out, which is just where you can get caught.

We take a flat-head screwdriver, press it against the fragment and, using impact movements at an angle in the direction of unscrewing the thread, carefully turn the fragment.

This method is suitable if it does not require much effort to unscrew. If the effort is not enough, then move on to the second method.

Method two: try to unscrew it with a chisel

This method is similar to the first, but instead of a screwdriver we take a chisel. In the same way, we rest against the splinter and use percussive movements to turn it out.

A chisel makes it possible to create more force compared to a screwdriver.

Third method: core and hammer

If the bolt fragment does not have splinters, or even the breakage occurred just below the final surface of the thread, then you can try using a core.

We rest the core against the surface of the fragment with an offset and, with blows at an angle, we turn it out until the fragment can be hooked with pliers or another tool.

Fourth method: weld the nut by welding

In my opinion this is the most effective and quick option, but if you have welding machine. Its essence is to weld a nut onto a piece of bolt on top.
So, to do this, take a nut, but not the same size, but a couple of units larger. That is, if the broken bolt was 10, then take a nut 12. This is necessary for a better and larger welding site.

Holding the nut with pliers, we place it on the fragment, but not in the center, but offset. Using an electrode, we weld the stud and nut to one side inside the nut.
Then, after cooling, unscrew it with a regular wrench.

Fifth method: unscrew the pin with an extractor

Here you will also need a specialized tool specifically designed for unscrewing broken studs and bolts - an extractor.

We center the pin so that the drill does not run around when starting to drill.

Drill a hole of the appropriate diameter for the extractor.

We insert the extractor into the hole and unscrew it with a key.

Sixth method: drill out the fragment

The method is to select a drill according to the lower diameter of the stud thread and drill it out. A very difficult method that requires skill.
First we go through a drill of a smaller diameter.

Then we drill as close as possible.

We knock out the fragments and remnants of the stud with a flat screwdriver.

This method of removal is not always worth the effort, but it deserves your attention.

Seventh method: drill a clean hole and make an insert

The most time-consuming and expensive method of all. But there are times when this is the only working option to return the node to working condition.
We drill out the stud cleanly along with the thread.

We cut a new thread with a tap.

You can finish here if the design now allows you to select a thicker bolt or stud. If not, we buy an insert or order it from a familiar locksmith.
Lubricate the external thread with thread locker and screw it in.

Stitch flush.
What method did you use? Write in the comments, I think your experience will be interesting! All the best!

Over time, the metal from which the fastener is made gets tired, becomes less durable, breaks easily, and the thread, accordingly, can easily be torn off.

In this case, it becomes more difficult to unscrew the bolt, but knowing several ways, you can handle it.

What to do?.

How to unscrew a bolt

You will need

Pliers;

Wire cutters;

Nail puller;

Glue "Liquid nails";

Screwdriver;

One more hardware;

Set of extractors;

Drill with a smaller diameter drill bit.

Step 1. Try to pry the bolt with a puller or nail puller and pull it out as far as the stripped thread will allow. Next, without removing the tool, unscrew it with a screwdriver or wrench, depending on the design of the bolt.

Step 2. If you don't have a nail puller, slide a flathead screwdriver under the head of the bolt, press it against something to create a lever, and gently tap the handle of the screwdriver with a hammer - the bolt will gradually come out of the hole. At this time, try to tighten the bolt counterclockwise with a screwdriver.

Step 3. Try to remove the small bolt with wire cutters. Simply hold the cap between the jaws of the tool and pull it towards you with force. If the thread is completely broken, it will come out without difficulty, and if not completely, turn the pliers together with the bolt counterclockwise.

Step 4. If the head of the bolt has slots for a screwdriver, the problem is that it is impossible to apply force in the desired direction, since the bolt rotates. To fix this, sharpen the head under the adjustable wrench or simply make two cuts opposite each other using pliers. Grab the cap and unscrew it, while pulling the bolt towards you.

Step 5. Buy a set of extractors - several taps with reverse threads. Drill a hole 3-15 mm deep in the bolt with a drill smaller than the internal diameter of the hardware. Select the extractor size and screw it counterclockwise. At the moment when the cone, tapering at the bottom of the tap, reaches the end, the bolt will begin to rotate with it - at this moment, begin to unscrew the torn bolt in the desired direction.

Step 6. On a bolt with a broken thread located in hard to reach place, drop a little metal glue, for example, “Liquid Nails,” and glue another piece of hardware. Degrease the surfaces first. Once completely dry, try removing both bolts together by pulling the glued one towards you and turning it along the thread.

How to remove a bolt

Imagine a situation when, in the process of repairing equipment, you need to disassemble some component, but you cannot do this because one of the mounting bolts does not have a head. The situation is well known, do not despair. There are a few enough simple ways solutions to this problem.

Step 1. If, for example, the break point of a bolt is located in close proximity to the surface of the part, then it is worth resorting to the help of a sharp core. Place it at an angle to the edge of the bolt and, lightly hitting it, try to give it counterclockwise rotation (for a bolt with a right-hand thread). Sometimes this is quite enough.

Step 2. Another option can be implemented using a grinder, provided that top part The “decapitated” bolt protrudes at least slightly above the surface of the part. Cut a slot for a screwdriver in it using a thin cutting wheel measuring 0.8-1.00 mm and you can begin removing the bolt.

Step 3. The next one is probably the most reliable way- using a tap with a left-hand thread. First, make a mark in the center of the bolt with a core and drill a hole with a diameter 2-3 mm smaller than the bolt and a depth of 10-15 mm. Then start screwing the tap into the hole until the resistance to its rotation begins to exceed the friction force of the bolt thread, after which it begins to turn out.

Step 4. In the absence of a tap, you can try to remove the bolt using a screwdriver, the edges of which are sharpened to a cone so that it fits into the hole. For more reliable fixation in the hole, the screwdriver should be lightly struck several times with a hammer.

Step 5. You can also use a right-hand thread tap to remove a broken bolt. As soon as the bolt begins to go deeper, start turning it out. The next method involves the use of welding, but only under three conditions: a) if the bolt has a diameter of more than 10-12 mm; b) the welder is highly qualified; c) the break line is close to the surface (in this case, you can try to weld a piece to the broken bolt metal and use it to remove the bolt).

Step 6. In the most extreme case, when all of the above methods could not be implemented, all that remains is to drill out the bolt with a drill whose diameter matches or is close to the diameter of the bolt. After this, you should drill a hole for a new thread. bigger size. For example, when threading M8, make M10 or M12.