EdupradaOften overlooked, the engine mount, also called an engine silent block, is an essential part for absorbing vibrations and thus guaranteeing a better lifespan of the various elements of your car’s engine. The engine mount is one of the many silent blocks on your vehicle.
What is a silent block or engine mount used for?
The engine silent block , also called engine support , is made up of two mounting bases linked together by elastic material to absorb shocks and vibrations. The engine silent block therefore acts as a shock absorber for your engine in order to limit the propagation of engine vibrations throughout the rest of the car.
There are several types of engine silent blocks:
- The classic engine silent block : it is made up of an elastic part and 2 metal parts which are connected to the chassis and the engine. This type of engine mount is rather rigid and therefore cannot ensure ample movement of the engine.
- The anti-tilting engine silent block : this type of engine silent block can come in two forms. The first consists of a large cylindrical silent block with a metal spacer in its center. The second consists of a link with the spacer in its center and an elastic block on each side.
- The balance-type engine silent block : with this type of silent block, the entire weight of the powertrain rests on the engine support. Positioned horizontally, the engine mount therefore supports the gearbox on one side and the engine on the other.
- The hydraulic motor silent block : composed of 2 chambers filled with a pressure liquid, the hydraulic motor silent block ensures the best absorption of movements and vibrations of the engine.
Please note: your car has several silent blocks positioned in different locations but always providing the same shock absorber function. Indeed, there are stabilizer bar silent blocks, exhaust silent blocks, engine silent blocks, suspension wishbone silent blocks, etc.
When to change a silent block or an HS engine mount?
It is essential to know when it is necessary to change a defective silent block or engine mount to avoid costly breakdowns and keep your car running smoothly. Here are some guidelines to help you determine when to replace:
Visible symptoms : Pay attention to signs indicating a failing engine mount. Jolts when starting or accelerating, perceptible vibrations in the steering wheel, skipping gears or a clutch that chatters when changing gears can be symptoms of a silent block or an HS engine mount;
High mileage : although the average lifespan of an engine silent block is approximately 300,000 km, it is recommended to monitor the condition of your engine mounts regularly, particularly if your vehicle has traveled a significant distance. If you approach this threshold or notice signs of wear, consider replacement;
General vehicle wear : If your car shows other signs of wear, such as unusual noises, steering instability or suspension problems, it is advisable to check the condition of the engine silent blocks. Faulty engine mounts can make these problems worse and cause additional damage;
Preventive maintenance : as part of the preventive maintenance of your vehicle, it is recommended to have the engine mounts regularly inspected by a professional. They will be able to assess their condition and advise you on the need for replacement.
It is important not to neglect replacing a faulty silent block or engine mount, as this can lead to more serious and costly problems in the long run. If you observe symptoms of wear or have doubts about the condition of your engine mounts, consult a qualified mechanic who can provide you with an accurate assessment and carry out the necessary repairs.
What are the symptoms of an out of order engine mount?
Engine mount wear is most often detected by paying attention to the noise and vibrations of the vehicle while driving. Therefore, when the engine silent blocks fail, the following signs can be observed:
- Jerks when starting or accelerating ;
- Your speeds jump during these jerks;
- You feel vibrations in your steering wheel ;
- Your clutch chatters when changing gears.
How to change a silent block or engine mount?
Changing the engine mount is a relatively simple operation but requires proper tools. In fact, you will need to keep the engine and gearbox raised while replacing the worn or broken silent block.
Necessary material :
- Jack
- Candles
- Complete toolbox
- Protective gloves
- Protective glasses
- Wooden block
Step 1: Raise the car
Start by putting your car on jack stands so you have access to the underside of the car. Be sure to do this on a flat surface so that your car remains stable throughout the procedure.
Step 2: Position the jack under the engine
Now that your car is raised on jack stands, you can position the jack between the gearbox and the engine. Use a wooden block between the jack and the engine to ensure better engine support during the intervention.
Step 3: Access the Engine Mount
Depending on the engine mount you want to change (left, right or lower silent block), you will need to remove certain elements to be able to access it.
For the left engine mount, that is to say on the gearbox side, or on the right when you are facing the hood , you will generally have to remove the battery in order to access it.
For the right engine mount, on the distribution side, or on the left when you are facing the hood, you will generally have to remove the coolant system to gain access to it.
The lower bracket, under the car, is the simplest because you don’t have to remove anything to access it. No need for a jack to support the engine either since it will just have a pendulum effect that you can adjust by hand.
Step 4: Remove Faulty Engine Mount
Make sure the jack is still in place and supporting the engine properly. If everything is correct, you can start removing the engine mount mounting bolts. Once all the tightening bolts have been removed, you can remove the silent block from its location.
Step 5: Install the new engine mount
Put the new silent block in place then retighten the fixing bolts. Pay attention to the tightening torque of the bolts since these are parts that will support the entire weight of the engine. Consult the technical documentation for your car to find out the tightening torque to exert on each bolt.
Then replace all the elements that you had to dismantle to access the engine mount. There you go, your engine now has brand new engine mounts.
How much does it cost to change a silent block or engine mount?
On average, an engine mount costs between €20 and €100 . However, the price may vary depending on the type of engine silent block. Added to this is the price of labor, which can also vary greatly depending on the model of your car. So count on average between €80 and €500 for changing the engine mount.
You now know everything about the engine silent block. As you have understood, the part can last the life of your car but must be replaced if worn.