Just wanted to pass on my experience - as it might help you. I bought a pair of engine mounts for my '95 E320, as when the car idled in gear, there was a noticeble vibration inside the passenger's compartment. I removed the plastic "belly" pan from under the car, and jacked it up under the front crossmember. The placed two floor jacks on either side of the hydraulic jack, and lowered the jack. Then, undid the fan shroud ring and pushed it toward the engine. This will allow you to jack up the engine and not push the fan into the shroud.

From underneath the car, I loosened the two engine mount bolts (17mm) and removed them. Up top, the challenge began. I found that you get much more room to work when you lift the engine up a bit. I used a wide, 2" x 6" piece of wood under the oil pan, and carefully lifted the engine.

OK - the RH side mount (passenger side) was a pain. Either get a stubby 17mm wrench or you're going to want to unbolt the mount assembly from the side of the block (which I did - just four 13mm bolts). There is just not enough room to get a socket or even a wrench on the single bolt in the top of the engine mount (exhaust manifold is just above this area). I then was able to pull the whole assembly and remove the bolt (top of motor mount to motor mount housing) on my bench. Then put the new mount in place on my bench, and torqued down the top bolt. Going back was fine, just had to use a prybar to encourage the motor mount to align with the hole in the bottom of the car's chassis (facing the ground). Beware that your old mount will be very compressed, and you'll have to get the engine as high as you can to get the new mounts in place.

Believe it or not, the LH side mount was much easier. With a 3/8" ratchet and short 17mm socket, I was able to maneuver my left arm behind the throttle linkage (under the intake plenum) and put it directly on the top bolt of the engine mount. It came right out. Assembly on this side - I threaded in the top bolt first - slightly and the bottom bolt next, then dropped the engine. Then made sure both sides were tight. Put the shroud back on and drop the car to the ground.

Idling is great. Startups are quieter. Car drives great. I highly recommend the change if your mounts are original. I think it took me two hours (with me going inside to read my four year old a book before bedtime). Hope this helps - best regards, 71Rcode

congratulations!

I just don't know how the rh side was a pain... my top bolts come out real easy....in a 1988 300e....

Great post of the procedure in details.

Are motor mounts replaced more per mileage or age, and what's the usual schedule?

Impala - thanks. I think the best posts I read on this site are when guys totally explain a procedure. Whenever I take on a task, I'll spend a few minutes writing up how it went for me. A little thing like that can make a "can fix" decision for a guy, and end up saving him $$$. To answer your question, I don't know. I would think that with age/mileage, the mounts should be replaced. My wife's E320 has 85k on it. And those mounts were worn. So, I don't think it's a bad idea for anyone with a W124 model.

Lee - must be a different exhaust-to-motor mount clearance configuration on the earlier 300E models. I wish mine would've been that simple!

The Star Magazine had an article on how to change engine mounts. I will look for the date if there is interest.

My local shop would like $175 total + the parts I provide to change out the trans mount and the 2 engine mounts on my 89 300E... is that fair?

I am really nervous about lifting the engine....

I am still trying to figure out which mounts to buy... could someone assist?

__________________
2006 BMW M5 "Heidi" @ 109,000 miles
2005 MBZ C55 AMG "Lorelai" @ 165,000 miles
1991 MBZ 300E "Benzachino II" @ 165,000 miles
1990 MBZ 500SL "Shoshanna" @ 118,000 miles

(On the hunt for a good used M103 engine as of 6/10/23, PM me if you have one to sell!)

Tranny mount
http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1D00YU6RY1GP19MM7Z&year=1989&make=MB&model=300-E-002&category=J&part=Transmission+Mount
Motor mounts depends on tranny type. [ man/auto.]

Just finished this job on my 94 E320 cabriolet.

I did the engine mount arm removal on both sides after trying to break the bolt loose on the top of the mount on the driver's side. I couldn't get the right combination of tools and with the limited swing I didn't want it to suddenly break loose and bang up my hand. I'm also currently dealing with a bad shoulder which requires me to be very careful if I don't want severe pain. There is absolutely no room on the passenger side to get at this top bolt for the mount as mentioned. It's reasonably easy to access the four mounting arm bolts, and then chuck up the arm/mount in a vise and break loose.

As reported the difference between old/new is amazing. Next on the list is replacement of the two mounts on my 95 E300 diesel. I did note that access on the diesel OM606 engine is much less restricted, and I can get a socket on both left and right hand top bolts, which means I do not have to remove the arms for this application.

Jim

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14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles

Lee, the later car is a V6 - whole different ballgame.
Yeah, jacking the engine is not really too bad, as long as you go slow and track down any binding hoses or cables before going up too far. Old stiff AC hoses and steering hoses need to be watched closely.
I jacked up my m103 I6 in my '91 SE awhile back high enough to get two hockey oucks under each motor mount - and the oil pan just literally fell out with all that additional room.

DG

Oops, my Bad; the '95 is a M104 I6. Probably a lot of extra smog stuff on there.
More coffee,
DG