What does the engine mount do and how is the engine connected to the mount?

The engine is fixed on the body frame by connecting with the bracket. The role of the engine mount is roughly divided into three points: "support", "vibration isolation" and "vibration control". Well-made engine mounts not only don't transmit vibrations to the body, they also help improve the vehicle's handling and steering feel.

What does the engine mount do and how is the engine connected to the mount (2)

Installation structure

A bracket is placed on the front side member to hold the upper end of the engine block on the right side of the vehicle and the transmission on the rotational axis of the power unit on the left side. At these two points, the lower part of the engine block oscillates mainly back and forth, so the lower one is held by the torque rod in the sub frame position away from the axis of rotation. This restrains the engine from swinging like a pendulum. Additionally, a torsion bar was added near the upper right bracket to hold it at four points to adjust for changes in engine position due to acceleration/deceleration and left/right lean. It costs more than a three-point system, but reduces engine jitter and idle vibration better.

What does the engine mount do and how is the engine connected to the mount (3)

The lower half has built-in anti-vibration rubber instead of a metal block. This position is where the weight of the engine comes in from directly above, not only attached to the side members, but also pulled out of the mounts and attached to a solid part of the interior of the body.

Different cars use different materials and structures, but generally there are only two fixed points for engine installation, but Subaru has three. One on the front of the engine and one on the left and right on the transmission side. The left and right engine mounts are liquid-tight. Subaru's installation method is better balanced, but in the event of a collision, the engine can easily shift and fall.


Post time: Jul-09-2022