Replace your upper engine mount bushings with polyurethane
The 850’s upper mount is designed to hold the engine in place. Without it, the engine would thrash back and forth in the bay and damage everything near it. Overtime, these bushings hold on to that engine every single day. It’s a tough job. Eventually, they wear out and crack, requiring replacement. Thankfully, it’s an easy DIY job you can do in an hour.
Today we’re giving an overview of how to replace these upper engine mount bushings.
The bushings are 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 vibration felt in the cabin to violent shake and sounds from the bay. The upper 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 torque arm (you don’t replace this, though you will remove it temporarily).
Polyurethane bushings have a lot of benefits over their rubber OEM counterparts. They allow your engine to provide more immediate power to the transmission, as polyurethane is a bit stiffer than rubber, which doesn’t allow the engine to physically roll as much. They’re also much more durable than their rubber counterparts, lasting much longer. The downside to polyurethane components, however, is the stiffness itself, which allows vibrations to move through bushings into the frame a bit more easily.
On the Volvo 850, polyurethane bushings have another serious benefit. Replacing the bushings with original OEM rubber bushings creates some serious headaches during the replacement, as the bushing is a single piece that must be forced onto the mount. This sounds easy enough, but it’s virtually impossible to do by hand and you need some special tools to force it in. (If you’re interested in OEM rubber replacement, check out our OEM Bushing Replacement How-To.)
Nasty old, cracked bushing causing vibration in the steering wheel:
Polyurethane bushings though come in 2 pieces, so all you need to do is remove the old bushing and slide the two pieces in on each side to meet in the middle. Removing the old bushing and installing the new one is pretty simple. The how-to guide above offers more in-depth directions that you can tweak for poly bushings, but in essence you simply:
- Remove the torque arm connecting the bushing to the firewall (remember, these mounts aren’t actually holding the engine up, so it’s okay to remove them).
- Slide the bolt out of the torque arm and bushing (you can see the bolt and part of the torque arm in the picture above).
- Cut out the old bushing with a hacksaw.
- Slide in the 2 pieces of the new bushing.
- Put it all back together.
- Open beer.
If you’re looking to replace the actual engine mount as well, consider going with an OEM piece. It turns out the OEM piece 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.
If you’re interested in replacing the two lower mounts that are responsible for the engine’s weight, check out our post on How to Replace Volvo Lower Motor Mount.