Importance of Engine Mounts
conical mounts_EMIf you put a fragile item into a box and shake it
around, it will probably become damaged. The item may even damage
the box itself. However, if you secure the fragile item using rods
and cushions to hold it in place, it will stay still when the box
is shaken. Engine mounts work in the exact same way.
Engine Mount Form
Engine mounts can be of various designs or form depending on the
application and amount of energy they need to absorb. Because of
this, most engine mounts are relatively small or just large enough
dampen and absorb the energy without taking up too much space.
There are a few parts that go into an engine mount. One of these is
the molded rubber bushing or mount which acts as the vibration
control and cushion. The engine will typically be attached directly
to this part. There will also be a bolt that goes through the
length of the motor mount, which is used to secure it. The purpose
is to make sure there is a rubber break between the two mating
surfaces. Some motor mounts have a metal cover over the rubber part
to provide more stability.
Engine mounts are made in a variety of shapes. They can be large,
with multiple mounts connected to a frame. Some are also made with
hydraulic fluid on the inside to provide more damping and
flexibility. The shape, size and materials of an engine mount
depends on how much load is applied to the mount and how much
energy the mount needs to absorb or dampen from transmitting to the
support frame.
Function of an Engine Mount
The function of an engine mount depends on the vehicle that it is
needed for. Here are the four most common types of engine mounts:
Single piece isolator: These can be used as the front or rear
mounts of an engine set. They tend to be best suited for stationary
applications (Gen Sets, In plant power, etc) as there is only an
elastomer on the top portion of the mount.
Hydraulic Engine Mount: engine mounts with hydraulic fluid absorb
more noise and vibration. The internal fluid is “pushed” through
internal orifices to provide a controlled spring rate. These are
most common in vehicles with four cylinders or more, such as large
trucks and buses.
Two-Piece Mounts: These are great for applications that have high
rebound load s - such as off-road equipment. Think of the need to
isolate in both directions.
Base plate for flange mounts. These are for applications where ease
of installation is required. These mounts have a base flange that
can easily be fixed to a floor or base structure with bolts. No
need to recess or insert into a frame. These are commonly used in
applications where there is plenty of space to accommodate a mount.
Rubber Engine Mounts
The best material to use for engine mounts is natural rubber. Here
are some reasons why you should choose rubber for your engine
mount:
Versatile in the shapes and configurations to adapt to many
different applications.
Excellent vibration and noise dampening
Long lifespan - correctly selected, a rubber isolator can outlast
the engine it is protecting.
Provides a balance between energy absorption and stability for the
engine - these are often in conflict.
Resistant to ozone, water, oil and other damaging fluids/elements -
giving them the ability to perform under tough conditions at low
cost.
Natural rubber is the most widely used and common as it is the best
material for resiliency or the ability to go back to its original
shape. The ability to return to its original shape and not to stay
deformed (compression set) is an important characteristic. Is it
always the best choice? The best material is determined by what
fluids and environmental conditions the mount will be exposed to.
For example, if the mount will be in constant contact with oils or
fuel then Neoprene will be a better choice. Constant exposure to
sunlight or UV? Then EPDM is the best bet. Need to operate at
extreme heat or extreme low temperature? Silicone is the one you
need. Need some help choosing the right material? Contact the RPM
Industrial Rubber Parts team, we have got your back.
Because engine mounts are made of rubber, it allows for unique
customization. OEMs can design mounts that will fit the application
rather than design the application to fit the mount. Have a mount
that has been discontinued? Let our experience match you up with
the best part or guidance to move forward. An OEM may also get
custom motor mounts made for a few other reasons. With
customization, manufacturers can choose the material, shape,
colors, size and more.
Benefits of Using good quality, Rubber Engine Mounts
Reduce excess vibration and noise
Keep engines from sustaining damage
Extend the lifespan of the engine and connected sensor components
Keep transmission and other vital parts from sustaining damage
Engine mounts are designed to absorb the energy of the system and
become worn out after a while and may require a replacement. It’s
important not to wait to replace your engine mount or your vehicle
may be damaged.