Installation Instructions in the E46 chassis:
- Part name: E46 Motor Mount Bushings
- Part number: K0103-80/95/AL
- Product page: Link
- Difficulty level: 4
E46 Engine Mount Replacement Guide
One of the most neglected maintenance items on a BMW is the engine mounts. It's very hard to tell when an engine mount has failed unless you know what to look for. Because a lot of BMWs use hydraulic engine mounts they can be completely failed and still appear to be just fine. What actually happens in these cases is the hydraulic fluid from inside the engine mount will leak out. This will cause the engine mount to collapse. But not enough to be noticed by the novice automotive enthusiast. Aside from the usual cracks and tears in the rubber, things to look out for are brown fluid residue on the engine mounts or subframe, excessive vibration at idle, and the engine's oil pan sitting abnormally close to the subframe. These are all symptoms of worn or collapsed engine mounts. In this article, we will cover the basics of replacing engine mounts.
Raising The Vehicle
- Two Floor Jacks (one is acceptable)
- Four Jack Stands
- Mechanics Gloves
- 1/2" Electric Impact (breaker bar and socket are fine)
*Skip step 1 if you have a 1/2" impact*
Step 1: Break the wheel bolts or lug nuts loose half a turn with a socket and breaker bar before raising the vehicle.
Step 2: Jack the rear of the vehicle up as high as you can. To do this you'll want to put the jack under the rear subframe on the section that wraps around the diff.
Step 3: Place jack stands under the rear side lift pads. Be sure to get them as high as possible while still being sturdy.
Step 4: Lower the vehicle on to lift pads. Make sure the vehicle is secure and not rocking on uneven stands.
Step 5: Using both jacks at both front lift pads, evenly raise the vehicle until it is level with the rear jack stands
Step 6: Place the second set of jack stands under center frame rails at front of the vehicle.
Step 7: Lower the vehicle on to jack stands. Make sure the vehicle is stable and not rocking on uneven jack stands.
Step 8: Using 1/2" impact and socket remove rear wheels and place to the side.
Removing Engine Mounts
- Floor Jack or Engine Hoist (Engine Hoist Preferred)
- Small Block of Wood (Distributes the load between the jack and oil pan to support the engine)
- 1/2 or 3/8 Impact
- 13mm/16mm/17mm Sockets
- Swivel Extension
- 13mm/16mm/17mm Open Ended Wrench
- 3/8" Ratchet (A swivel head would be ideal)
- Pry Bar
Step 1: Once the vehicle has been raised you'll need to loosen or remove the 13mm nuts that hold the transmission mounts to the transmission brace. This is necessary to allow the engine to move up out of the way.
Step 2: Remove 8 13mm bolts from the front skid plate using 1/2" impact and remove the skid plate from the vehicle.
Step 3: Using the 16mm socket, swivel extension, and ratchet unbolt the two lower nuts holding the engine mounts to the subframe.
Step 4: Use the 3/8" ratchet and the 16mm socket or the 16mm open-end wrench to remove the nuts connecting the engine mounts to the engine mount arms.
Step 5: If using an engine hoist connect the hoist to the hook on the front of the engine and slowly raise the engine being sure to keep an eye on all accessories to make sure nothing is being pulled or damaged. If using a floor jack. Place the small block of wood on to the jack's lift pad and place it on the front passenger side of the oil pan. Slowly raise the engine until both engine mounts are able to be removed.
Step 6: In some cases, the passenger side engine mount arm may need to be removed. To do this unbolt the 4 13mm bolts holding the engine mount arm to the block and the 13mm nut holding the engine ground to the frame rail.
Step 7: Remove one engine mount at a time you may need to rotate the mount while removing it to release it from the subframe.
Installing Engine Mounts
Step 1: Install engine mounts in reverse order of removal.
Step 2: Using engine hoist or floor jack slowly lower engine. While lowering carefully guide the engine mount studs into the engine mount arms. If you are having trouble lining the studs up using a pry bar to move the engine left or right can help line them up.
Step 3: Thread the provided 17mm nuts on to the upper and lower studs of the engine mounts and torque to spec - Polyurethane (80a,95a) = 12-15ft/lbs, while Aluminum should be torqued to 25-33 ft/lbs.
Step 4: Tighten the transmission mounts and torque to spec - 12-15 ft/lbs
Step 5: Don't forget to torque your wheel bolts or lug nuts! ~85 ft/lbs