A motor mount is a critical part of a vehicle that keeps the engine in place. It is used to align the engine into position because, if the chassis is not isolated from the engine and the transmission, the vehicle can experience excessive noise and vibration because the engine is unable to perform smoothly. The mounts consist of rubber insulator blocks and metal plates which are essential to the car's performance.
Rattling and Vibration
Rattling and vibration are the most basic signs of a broken motor mount since its function prevents these symptoms from occurring. If you notice a continued rattling or feel the car moving and vibrating as you drive, you may want to check for other symptoms of a broken motor mount to confirm that this is the cause of the problem.
Engine Out of Place
The mount can break if the rubber separates itself from the steel. When this happens, the engine does not necessarily break away, but instead jerks and twists during acceleration or while carrying heavy loads. An engine that is out of place from its original position is another sign of a broken motor mount.
Parts such as the radiator, exhaust system, wiring connectors and heater hoses can become overworked if a car has a broken motor mount. All these parts are intricately linked to one another and placed in close proximity to the mounts and the engine. When the mounts are broken, these parts can heat up easily due to excess contact with the engine, preventing the vehicle from running smoothly. In the case of rear-wheel drive vehicles, the broken mount may put enough pressure on the engine-cooling fan to either snap or slam against the radiator. You may also hear creaking noises when the pulleys or drive belts start developing friction as a result of their inability to move about freely.
Excessive torque is another sign of a broken motor mount, especially in front-wheel drive vehicles. When the mounts snap, the engine may move in such a way that it interferes with the throttle or gear lever. This can lead to leaks in the exhaust. This usually happens in the area where the manifold joins the main exhaust pipe, or the pipe may collapse. If the broken mount happens to be an end-mount (at the end of the chassis, transmission or engine), this can also lead to torque steer as the engine's power pulls the steering wheel in one direction or the other.