The engine support (engine mount) is designed to reduce vibration loads and oscillatory movements of the internal combustion engine in the engine compartment, as well as to minimize the transfer of such loads to the vehicle body. In other words, the engine is attached to the load-bearing elements of the car body not directly, but with the help of special supports, which are also called cushions.
Simply put, the engine mount is the gasket between the engine and the body. Naturally, any problems associated with the engine mounts lead to the fact that the efficiency of the engine mounts decreases and severe discomfort occurs. Also, for a number of reasons, the operation of the vehicle may become significantly more complicated.
Next, we will talk about what signs indicate that the power unit mount is torn, as well as how to diagnose and check engine mounts.
What is an engine mount (mount) and what is it intended for?
Engine mounts are special units with which the engine and gearbox are secured to the frame, subframe or body of the car. To perform its job reliably, the support must have high wear resistance and strength. Therefore, the design of the part is a steel base equipped with rubber pads in the areas of the junction with the motor. It is the latter that dampen the vibrations produced by a running engine.
In addition to absorbing vibrations, the support serves as a shock absorber for the engine, preventing mechanical damage after hitting uneven road surfaces.
Rubber-metal engine mounts
Main functions of engine mounts:
- To absorb shocks and jolts that occur when the vehicle is moving.
- Ensure effective vibration isolation of the passenger compartment at idle.
- Provide less wear on parts by reducing engine sway.
How to determine whether the supports are working or not?
There are several ways to independently check the status of these devices. You can try to rock the engine with your hands. By knocking on a certain side, it is easy to localize the faulty mechanism. Another common diagnostic method is when the hood is opened and locked, the engine is started, after which the car jerks forward and backward. This way it will be possible to determine whether the unit is moving and returning to its original position with a knock.
Hydraulic cushions can crack, which will cause leakage of working fluid from the system. Supports with damaged rubber gaskets are unsuitable for further use and should be replaced as soon as possible. It is easy to identify mechanical damage and defects, for example, separation of the rubber part from the metal, at the time of maintenance of the power unit. Any destruction of the pillows is a strong argument in favor of replacing them with new, original copies. In order for the new kit to fully exhaust its service life, you must follow a number of simple steps:
- periodically check the tightness of nuts, bolts, and other fasteners;
- remove traces of engine oil and dirt from the surface of the supports;
- operate the vehicle calmly and moderately;
- prevent any critical loads on the engine or chassis of the car;
- use original supports or analogues from trusted manufacturers.
It turns out that operating a car without vibration and vibration dampers is simply impossible. That is why it is important to monitor their condition and replace them in a timely manner. Now the range of products on the market of spare parts and components for cars is incredibly diverse. Car owners often face difficulties in choosing new supports and understanding their average cost from different manufacturers. In such cases, you can use services that will show the average cost of engine mounts in your region.
Domestic drivers, according to reviews, give preference to German products (the production of pillows is carried out by the German company FEBI , which produces high-quality products at an affordable price). Many automobile concerns already install devices from SWAG - another manufacturer from Germany that relies on multi-level quality control. Engines of French cars come off the assembly line with airbags from SASIC - the optimal solution for those who spend time driving Peugeot, Citroen, Renault.
Number and location of engine mounts
The location of the supports is not known to many car owners until strong vibration begins when the engine is running. Then the details will attract attention themselves, although they are not always visible under the hood. Most often, without special training and knowledge, you can only see the upper support.
The main factors that determine the number of engine mounts and their location are the weight and position of the power unit in the engine compartment, as well as the type of vehicle body.
As a rule, 3 or 4 ICE supports are used to secure the power plant. Moreover, three-point fixation is the most common among almost all manufacturers. Despite the different method of location and method of their fastening, the fixation must be so reliable that there is no significant displacement of the motor during vehicle operation.
In addition to the engine, the transmission is also mounted on rubber-metal mounts. Therefore, it is necessary to distinguish between the gearbox and engine mounts.
Don't joke with silent blocks!
Engine mounts, like other parts in your car, are subject to wear and tear. This is especially true when the support has rubber elements. Like any other malfunction, failed airbags manifest themselves with certain symptoms. Signals to visit a car service center can be:
- increased vibration spreading throughout the body;
- unusual knocks under the hood when driving on rough roads;
- knocking sound in the front of the car when braking or when starting off;
- grinding noise when changing gears.
If you notice something like this on your car, don’t hesitate. Although at first glance, if an engine mount fails, nothing but discomfort will result, in fact, in this case, the power unit itself is in serious danger. Drop everything and change the engine mount silent blocks.
Types of engine mounts
For specific models of their cars, manufacturers develop different power plant supports that have optimal rigidity indicators. If the rubber on the metal frames of the parts is less hard than necessary, then the engine will sway strongly when driving.
Operating principle of hydraulic support
Currently, engine mounts are represented in two large categories:
- Hydraulic.
- Rubber-metal.
Most often, “rubber” ones are found on domestic cars or older foreign cars. Their design is very simple, low cost and provides reasonable quality in performing their direct functions. Hydraulic cushions are installed on cars of foreign manufacturers. The parts are distinguished by more comfortable and convenient use, as well as high efficiency and wear resistance.
According to the type of control, hydraulic supports are:
- mechanical;
- electronic;
- dynamic.
The dynamic bearings were developed by Porsche's engineering team and implemented on its own sports car in 2011.
Typical faults
If, while driving a car, a characteristic knocking noise has become clearly audible from under the hood, more precisely, from under the lower part of the engine or in the transmission area, if noise and vibration increase during the switching from 2nd to 4th gear, then this may be associated with malfunctions in the suspension or engine operation. Depending on the condition of the road surface, these sounds may become louder.
If the car is operated for a long time under conditions of severe loads or temperature changes, then all this does not have the best effect on the condition of the engine mounts. Over time, rubber loses its elasticity. In addition, the pillow may delaminate or crack, or even collapse.
But it is worth considering that the service life of these parts is quite long - more than 100,000 km. The supports are subjected to high loads when the vehicle starts and during braking. If the car owner likes to drive fast enough, with sharp jerks at the start, then the supports will not last their intended period.
Also among the typical faults is the breakdown of a metal aluminum bracket. This often happens when hitting a different obstacle. If there are oil leaks in the engine, it will definitely get onto the rubber part of the support. This lubricant can corrode the silent block and the support will fail.
Coolant also does not have the best effect on the rubber part of the cushion. Breakdowns in the system must be eliminated immediately. Do not overheat the engine. In addition to the cracked cylinder head, antifreeze from the expansion tank will also get onto the rubber parts. This will not have the best effect on their resource.
Removal and installation
If you look at the essence of the issue, you can replace the engine mounts yourself even with basic plumbing skills. Brief description of the process:
- we install wheel chocks, it is advisable to remove the “-” battery if the work will take place near the starter;
- dismantle the elements that block access to the fasteners;
- Using a small board or thick rubber, create a stop under the engine or gearbox near the cushion that needs to be replaced. The jack must be installed under the wall of the pallet to avoid dents. There is no need to create a lot of force, since the jack will only serve as a fulcrum. For engines and gearboxes with plastic trays, the stop must be found on the gearbox body or engine block;
- unscrew the mounting bolts and nuts. If, after unscrewing the nut, it turns out that the bolt is stuck and does not come out by hand, pry it off with a small lever. If you unscrew all the fasteners of the support, but it does not come out, try lowering or raising the engine a little with a jack. There is a possibility that the motor, being slightly distorted, pinched the pillow;
- Installation of a new support and assembly is carried out in the reverse order. As with removal, in order to install the support, you may have to adjust the position of the engine with a jack.
Replacing the engine mount if a malfunction is detected
If you need to replace the engine mounts, the signs of malfunction described above will usually allow you to get to the nearest car service center or your own garage on your own. But you should drive carefully, if possible at a speed no higher than 60 km/h. The rear or left cushion is usually subject to wear. A detected malfunction of one support will most likely entail the replacement of the second pillow. At the end of the inspection, you need to purchase the necessary spare parts in advance - you won’t be able to go get them by car while replacing the airbags.
- Preparing to replace the engine mount It is recommended to carry out work on replacing supports in a warm place, since the rubber used at low temperatures hardens and loses elasticity. This will significantly complicate the process.
It is also advisable to drive the car into an inspection hole and carry out the replacement from there, having first disconnected the battery terminals. They often begin to inspect the left front side of the engine, where the airbag malfunction appears in most cases and access to which is most convenient.A torn mount can be repaired, since the price of a new mount for a foreign car engine is about 2,000 rubles (and for an SUV it is twice as high). If the rubber element is damaged, the support will have to be changed in any case.
- Engine mount replacement process
First of all, protective elements are removed from the motor to facilitate access to the necessary parts. A jack is then placed under the engine to provide support while the mounts are removed. If the process takes place in a viewing hole, you can lay a wide, fairly strong board across it and install a jack on it.Next, the unit is raised with a jack until it is possible to freely unscrew the support being replaced. After unscrewing the mounting screws and removing the old support, a new one is installed in its place, and the operation is repeated in the reverse order.
Replacing a rear airbag is usually associated with certain difficulties. This support experiences the greatest loads during engine operation. As a result, all fasteners are deformed, including bolts. The shape of the fastener differs from other supports.
Here a jack will no longer be enough. To free the support, it is best to hang the motor from the upper beam. If this is not possible, you can build a crossbar on two glasses, lifting the engine with a jack in advance. In some car models, external components may interfere with troubleshooting and will have to be removed. It is more efficient to cut off a severely deformed pillow fastening bolt with a cutting wheel. Sometimes they try to align and unscrew such a bolt, but after a while it will still have to be replaced.
The old support often sticks to the frame and forms rust due to the accumulation of dirt. Oil or a product like WD-40 can help remove it. It is important to install the new rear support correctly. The arrow on the support should point forward, in the direction of travel of the machine. The rest of the assembly is carried out in reverse order.
After replacing the rear support, you can proceed to the right one. Here, too, there is a possibility of encountering deformed bolts, but a more serious problem lies in the generator or car air conditioning compressor located here. It is known that removing the compressor can lead to depressurization of the circuit and leakage of refrigerant.
If the repair takes place at a service station, it is better to subsequently check the air conditioner for possible malfunctions. Short-sighted car service employees sometimes remove the compressor themselves to save time, without warning the car owner about it.
In foreign cars, in most cases, the right engine mount is located closer to the front. Therefore, to access this cushion, the right headlight and radiator grille are often removed.
Some of the deformed bolts cannot be cut off even with a grinder, since access to them is limited by other neighboring elements or simply cannot be reached. In this case, it is better to use a regular hacksaw, cutting off the damaged bolt by hand.
This procedure will take much longer, but at least this way you will not damage adjacent parts and components. The new support is placed in place of the old one as usual, in reverse order. When installing the radiator grille, you need to be careful - the radiator honeycombs are sharp enough to cut yourself.
- Safety during operation
The most important thing is to fix the motor securely and safely. A second assistant is desirable for assistance and backup.
We recommend
“How to fill brake fluid: choose a brand and follow the rules” Read more
"Mazda Demio"
Signs of a malfunction of the left engine mount of the Mazda Demio are knocking and vibrations. The supports bear a heavy load. It is worth carefully monitoring the condition of the airbags; a faulty part can damage the engine. This car has three airbags: left, right and bottom.
The second is located near the engine oil filler neck. The left support is located under the battery. The lower one is located directly opposite the junction of the engine and automatic transmission. The methods for diagnosing a malfunction in this case are the same as for any other cars - this is a visual inspection and checking for play.
Novice car owners often wonder why the automatic transmission jerks when driving. There are many reasons for this. Can the automatic transmission jump due to faulty engine mounts? Yes maybe. Sometimes the car's behavior changes. Therefore, if extraneous vibrations, shocks, hums, or characteristic noise are noticed, then it is best to check the supports.
- How to flush the engine cooling system 4 ways to clean the engine radiator
- Do-it-yourself car engine washing
- Five main mistakes when flushing the engine cooling system
- What is the best way to flush a car's engine cooling system?
Conclusion
The engine mount not only protects the engine and transmission from premature wear, but also provides greater riding comfort. A routine inspection and simple diagnostics will allow you to determine the problem in advance, without waiting for unpleasant vibration to appear throughout the body. The appearance of additional noise distracts the driver from the road and increases the risk of an emergency. For this reason, every driver must be attentive to the “behavior” of his car and respond in a timely manner.
