Motor mounts are mounts created to securely fasten your engine and transmission to the subframe of your car. They are also known as engine mounts.
They are small blocks of rubber that are installed on top of steel brackets securely fastened in place.
The rubber is used to absorb the vibrations created by the working of the engine. Some mounts are filled with liquid to further reduce the vibrations felt.
They provide the engine with support to reduce the noise and disturbance generated by the engine.
They absorb vibrations and shocks so that you get a smooth journey when driving. Most cars will have 3 or 4.
As a general rule, engine mounts will need checking every 5 to 7 years.
If you drive a lot or regularly drive on unlevel ground, your motor mounts may need replacing more often.
What are the types of motor mounts?
Rigid mounts are, as the name suggests, immobile. They are welded or bolted into place on the frame of the engine.
They are commonly found in smaller motors. This is because they are prone to damage when subjected to lots of intense vibrations.
Rigid mounts give the best alignment between the engine motor and the mechanisms around it.
These mounts have a layer of insulation (usually rubber) separating the motor and the mount. This acts to reduce the noise and as a shock absorber for the vibrations. These kinds of mounts can prolong your motor’s life due to the protection the insulation provides the engine.
These mounts allow the engine to move slightly without compromising the functionality of the motor. They are more common in large motors as these require better levels of noise suppression. The insulation also reduces the impact of the motor turning on and off on the surrounding mechanics.
These mounts are the ones that contain a liquid of some kind to muffle sounds and vibrations. They may also contain a gel-like substance such as glycol or hydraulic fluid (usually found in brakes).
Hydraulic mounts are often in 4-cylinder motors as these are very noisy, but can be found in other noisy engines too.
Face mounts are bolted directly onto the motor casing and into the surrounding mechanics. These do not require a standard mount for installation.
Face mounting is also known as NEMA ‘C’. You can use NEMA ‘C’ adaptors to install face-mounted motors to cars designed with other motor mounts.
How long does it take?
This will depend on the condition of your car and its component parts. If there are many rusty bolts these will add a significant portion of time to the repair as they are hard to remove.
The job will be faster if only one motor mount needs replacing, but it will evidently take longer if you need to replace them all. Removing the engine is a delicate task and must be done carefully to avoid causing damage to it.
For replacing one mount, you should allocate around 1-2 hours. As a rule of thumb, allocate 6-7 hours for a complete motor mount replacement job. This will vary depending on your experience level too.
How much does it cost?
This really depends on whether you get them replaced by a qualified mechanic or you try to do it yourself. They are very labor-intensive to replace and this is what tends to drive the replacement costs up.
This is because the engine must be taken out of the car for the mounts to be replaced. This is a delicate operation as the engine is very fragile. Something as simple as rusty bolts can increase the labor time by up to an hour.
On some larger vehicles, replacement costs by a professional can reach between $1,000-2,000. You can buy most replacement bolts and mounts for between $50 and $200 at most auto parts shops.
The price will vary depending on the manufacturer and if they are liquid-filled these tend to be more expensive,
There are reports of people DIY-ing the replacement job for under $100 but we do not recommend this. The engine is a very delicate part of the car and you could cause serious damage if you mess around with the wrong parts.
How to know when to change your motor mount
If you hear a clunking or banging sound coming from under your bonnet, this may be indicative of a damaged engine mount. One of their primary functions is to reduce the impact of the engine vibrations. If you can feel anything off, this is a fairly strong sign you should get the mounts checked out.
Similarly, if you do not hear banging but you can feel the endive vibrating as you drive this could suggest motor mount issues. The fluid may have drained out or the rubber may be worn out - both of which should be sorted immediately.
If the positioning of your engine is off this can be due to the motor mounts. They ensure the engine is in perfect alignment within the hood of your car. If it tilts to one side or moves freely then your motor mounts are ineffective and need replacing.
If you leave this, the engine can become so loose that it jumps about under the hood. The impact on the engine can damage the small component parts and this can cause life-threatening accidents.
You should regularly check the appearance of your engine mounts for signs of wear and damage. Look for cracks, warps, and corrosion on the mounts. The rubber may also start to flake off. All of these dramatically reduce the effectiveness of motor mounts, reducing the car’s safety.
Should I replace it myself?
If you have some knowledge of car mechanics and have worked with vehicle engines before you may be able to replace the motor mounts yourself.
You will need all of the necessary tools and at least one other person to help you with the task.