Replace Upper Engine Mount with a Polyurethane Bushing, Volvo 850/S70/V70/C70
By Matt
Overview
The 850's
upper engine mount is designed to hold the engine in place.
Without it, the engine would thrash back and forth in the engine bay and damage nearly everything near it.
There are two lower engine mounts that are responsible for the engine's weight, but these are out of scope
for this How To section.
Original bushing after sawing and removal.
It's easily spotted at
the top of the engine a bit to the driver's side (North American). When it decays, the results can vary from
engine vibration felt in the cabin to violent shake and sounds from the engine bay.
The upper engine mount, as it comes from the factory, is a molded rubber piece a little smaller than a
baseball.
Replacement polyurethane mounts (about $20-40) are two
half-donut pieces that come together from either side of the metal arm (you don't replace this). In retrospect
I would have replaced my mount with an OEM peice after looking at the OEM that came out and reading about them.
It turns out the OEM peice has a certain engineered design that limits engine rock to two directions, and
conversely dampens engine movement in other directions. Apparently the 850's engineers built a certain degree
of movement into the design of the car.
Tools
hacksaw
hammer
ratchet set
adjustable wrench
Procedure
Remove the bolt that runs through the center of the engine mount. Put the adjustable wrench on one side
to keep it from turning while you use the ratchet to unscrew the bolt. When this is out take a hacksaw
blade and run it through the OEM bushing (there are holes). Cut the bushing from the inside out (cutting
approximately a half- or a quarter of a centimeter).
This photo
shows the original bushing that has just been cut. IMPORTANT: The hacksaw blade appears to be 'aimed' at
the bolt hole... but please, don't cut that. It should not look like you need to cut through any metal.
This is a much better illustration of what you need to cut:
Original bushing during sawing. Notice the small cut at the 11 o'clock position.
The next step is to remove the bushing after the cutting has collapsed the integrity of it. It should
pull out either side.
Line everything up, put in either half of the replacement polyurethane bushing (or the one peice of the
OEM replacement if you're concerned about keeping your Volvo running with the correct parts), keeping in
mind you may have to
tap the bolt through with a hammer. If the
holes are not lining up perfectly, get a friend to try to rock the engine back and forth while you push
and tap the bold. Don't forget the washers.
Conclusion
The hardest part is getting the old OEM bushing out. Like I said above, if I could do it over again, I'd
get the OEM version. Also, I think I feel now more natural engine vibration in the steering wheel because
the polyurethane replacement transmits a bit more vibration.
Reader Comments
When you fit the new mount rotate the top forward about 15 degrees as this
takes some of the 'shear' out of the thrust and the mount will last much
longer. I still have an OEM mount in and it is about 6 years old.
Hutchie
Instead of a hacksaw to cut the old bushing out use a narrow wood chisel and hammer. It is much faster.
Orr's Island
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