Replacing Engine &Trans. Mounts Need Help
 

What is the proper procedure to replacing [subject] mounts?I just ordered them from Fastlane for my 1989 420 sel.

ANYONE!

I have never replaced mounts on this particular model, but there should be no tricks to it. You will simply need to determine how they bolt in, raise the engine and replace mount one side at a time. Then raise the transmission just enough to change it.

Regardless of the model, there is most always something in the way, but after a few trips back and forth to the tool box, you will find the right extension, socket, universal joint or whatever, to get it done.

Good luck,

Should be a total of three bolts per mount. One bolt holding the arm to the mount and two holding the mount to the frame.

I'll be doing mine as soon as the mounts arrive, and in looking at the job, it looks like first you'll need a 19mm to get the main bolt. That bolt also appears to hold down the heat shield. Once that bolt and shield are out, lift the engine and remove the two cap screws (6mm allen I believe). Now slip out the old and the new in. Replace the two cap screws, lower the engine and install the main bolt and heat shield. Do one side at a time.

You must lift the engine at least a bit before removing the heatshield(s) since the old mount will have collapsed onto it, pinching it in place.

Disconnect /watch fan shroud and throttle linkage as you lift engine. You have to lift it further than you think.

Do NOT let the main bolt x-thread when re-installing. Have a bar handy to tweak the engine side to side to align hole if neccessary.

I'm planning on doing the same thing on my 126....what is the best way to jack up the motor w/o obviously damaging anything?

Thanks guys,as soon as they arive i will install them. Thanks for all your help.

mbtjc,
The best way is to have the front of the car up on ramps, block rear tires; then use a piece of wood(I use a scrap piece of 2x6) under the pan and a bottle jack. When you jack the engine up and you have the car on jack stands it does "groan" a bit and makes me nervous, so I use ramps.

bribenz,

could you share your method, tools, etc...???

Thanks!

What do you mean by using a lift? If you mean a full-fledged hydraulic lift, most of us don't have access to that type of thing. So I think a floor jack and a creeper is gonna be it for most of us! :) What size allen is the main bolt? What exactly is an anti-seize compound? What kind did you use?

Thanks a ton for the valuable info!

After reading bribenz' decription I realized I gave you the process for the 4.5. Granted, I haven't even looked at the mounts on the 560 yet but gambled something so simple would likely remain unchanged. Ooops!

Looked in the manual this morning and yup, the center bolt comes out the bottom. That appears, on paper, to be much easier than the 4.5 because the center bolts on the 4.5 are a real pain to reach.

Done
 

Mounts arrived today, I installed in about 2 working hours. Very easy job.

Now that I've been through it on the 126 a couple things to pass on. First, be sure to pull the two clips for the fan shroud. This will allow the shroud to move upward as the enigine lifts. You also have to remove the lower nut and bushing from the engine shocks to gain enough lift.

I started on the passenger side - the harder side. Harder because the starter is on that side and takes up some working space. I found that getting the inner mount to frame cap screw out required a little tool modification. I had to cut off about 3/8" of the short leg of a 6mm allen wrench to get that bolt out. My 6mm hex socket was too tall to fit between the mount at the arm, and I didn't want to remove the arm and the allen wrench was too tall and I couldn't get on the screw because I was hitting the starter. While I was at it, I cut about 3/4" off the long leg. This allowed me to use my 1/4" drive ratchet and a 6mm socket plus the 3/4" piece as a drive. Worked great.

Driver's side was much easier as there was more working room.

http://www.pe.net/~mktangas/mmount.jpg

You can see how much the mounts have collapsed over the years. Replacing the mounts took nearly all of the idle shimmy out, I can hardly tell the motor is running.

Mounts?
 

I noticed the mounts from Fastlane for my S500 range from $86.00 to $110.00, the dealership wants $154.00. Is there a difference between any of them?