Need a little help guys ... I have searched ALL the threads in the archive. While there are a bunch of them on mounts I couldn't find one on W124 V8's. I've got pretty much everything scoped and laid out ... except ... How do you get the old ones out?

The CD I have says to remove the forward portions of the exhaust. I'm prepared to break a feww bolts and deal with it but is this, in fact, the key step. It doesn't look as though removing the crossoverfrom the right bank of cyliders provides enough room to get the right side mount out. I need help ... thanks

Removing that pipe definitely provides enough room for mount removal as long as you have the means to raise the engine slightly to get the mount out of its hole.

If you are lucky you are looking at 30-60 min of work, if not.... well. You will need a number of tools (ratchet, universal joints, sockets and extensions, etc) for this job. Under normal circumstances and with the mounts just slightly collapsed you need to disconnect the exhaust pipe going from the left side header to the main pipe. Its the one that goes across the transmission. Then you disconnect the two lower motor mount retaining bolts on the crossmember of each side and loosen up the fan shroud and place it over the engine fan before you jack or lift the engine up. If you dont have an engine lift, put a piece of wood on a hydraulic jack and carefully raise the engine placing the jack under the oilpan.
If the upper bolts are not seized up through excessive vibration, you can now loosen the upper bolts and take the mounts out.
There's a heatshield on the right side protecting a steering balljoint, that will have to come off too (the heatshield) to make room for the pretty fat mounts to come out. Jack the engine up as high as you can without damaging the throttle linkage and they will come out rather easily.
In case the upper bolts cannot easily be broken loose you will have to disconnect all four bolts on each side that attach the engine carrier arms to the engine. Now you've got a loose enginemount-enginecarrier combo in there. You will have to wedge them inplace somewhere and brake the upper bolt loose.
It will be more difficult on the left side but with patience it can be done. If the mounts have been in there too long and are completely collapsed you will have to go through what I just described, if not it should be fairly easy. Once you have them out , putting the new ones in is the reverse of the same procedure, only you need to line up the mounts and the lower bolts after you have connected the mount with the upper bolt to the engine carrier (then re-attached to the block).
Even the worst mounts can be replaced. Its just a matter of persistence, heavy cursing and brute force. I once spent almost an entire day on two completely seized up bolts on a M119 in a W124. But in the end they all come out, one way or another and the resulting smoothness of the engine later on is more than worth the trouble. For some reason these mounts seem to go bad pretty consistently every 50k-75k miles. My 400E has 120K down and the mounts have been done twice now. The ones on M103 engine W124's seem to last quite a bit longer.
Good luck!
F.J.

__________________
F.J.
81 300 SD grey/palomino 168K miles
84 190E 2.3 black/grey 64K miles (wrecked)
85 190E 2.3 maroon/palomino 92K miles
88 300E desert red/palomino 204k miles
(made to look like a '94-95)
92 400E desert taupe/creme beige 120K miles
(converted to 94-95 E420 looks)

Thank you R.M and especially you, F.J. ... I think !!

Any body care to come over Saturday? All those over 250 with Steve Austin guns are welcome.

Will let you all know how it works out. The car has 108K on it. One mount is pretty much toast, the other not as bad so I suspect I'll reread F.J. 's post a couple more times and get mentally perpared for a long day.

Thanks again guys.

This thread is very informative to me, I am also thinking about changing the motor mounts on my 92 400E by myself.

My car now vibrates at idle, and does worst at 1000 rpm when shift lever in any gear, also the car shakes a little bit at 120kmph highway speed, I had tires balanced twice without any improvement.

Are those the reasons that drove you to have motor mounts replaced? My 400E has 200k km already, when I bought it, I didn't get the complete service record, so I am not sure if they are due.

Thanks.

__________________
99 BMW 540i 6-speed 110K Km
03 SAAB 9-5 wagon 80K Km
92 400E (Sold) 245K km
Still missing the days with the Benz, it kept me busy.

carman850:
Excessive, steady vibrations in "D" at idle are usually a surefire indicator of engine mounts gone bad. If you can feel rather strong vibrations with the tranny in D when you put your elbow on the doorpanel while at an intersection or so, your mounts need replacing. These cars should idle absolutely smooth in 'D" with no vibrations whatsoever. And to avoid excessive labor, they need to be done sooner than later as the vibrations usualy seize up the upper bolts and it becomes increasingly difficult to break them loose.
Your car shaking at higher speed is a different issue, could be the driveshaft support bearing gone bad or any of the front or rear suspension components. Sometimes loose control arm bolts can cause this. You might also want to check the steering dampner(cheap fix!).
Hope this helps.
F.J.

__________________
F.J.
81 300 SD grey/palomino 168K miles
84 190E 2.3 black/grey 64K miles (wrecked)
85 190E 2.3 maroon/palomino 92K miles
88 300E desert red/palomino 204k miles
(made to look like a '94-95)
92 400E desert taupe/creme beige 120K miles
(converted to 94-95 E420 looks)

Hi F.J.Lahme,

Is the procedure the same for the 500E?
What is the easy way to disconnect the exhaust pipe connection, I'm thinking of doing this this spring?
Also, can you elaborate on the driveshaft vibration? I have a vibration that comes up around 75 mph + (a natural speed limiter ) and just gets worse as the speed goes up, is there a test to eliminate components or should I just have a Tech figure it out? Thanks

Hi Ross,
to my knowledge there is no real difference. Pretty much the same. I'll look it up and post it later in more detail.
To get the pipe off you need to drive the car on two ramps or jack it up in the front. The connection to the righthand side requires a ratchet with socket and a wrench(12mm and 13mm either way) the left hand connection to the exhaust header a ratchet, a long extension and if I remember correctly a 13mm socket. Fortunately there is no nut on top, so its easy to remove and reinstall. You dont have to take the exhaust headers off, just the pipe on the left and a heatshield on the right and there'll be enough room for the mounts to come out.

Your vibration can have a number of causes, one of which can be the driveshaft support bearing, hard to say without looking at and testdriving the car. The others are:
steering dampner, incorrectly balanced front wheels, unsuitable tires, worn out ball joints, tierod joints, worn front shocks, worn rear control arm bushings/joints(if the car seems to handle a bit queer) perhaps engine and tranny mounts or something as trivial as loose bolts somewhere in the front suspension.
Where do you feel the vibration? Does the whole car vibrate or just the steering wheel? If you feel it in the steering wheel the culprit is likely to be found somewhere up front with steering or supension components.
I need a bit more info on your car to eliminate issues. Mileage?
Any suspension parts replaced recently? ect.
Do a visual inspection of the balljoints, swaybar bushings and tierods. Look for torn rubber. Check the front and rear wheels for play. Leakage on the steering dampner? etc.
Hope this helps.
F.J.

__________________
F.J.
81 300 SD grey/palomino 168K miles
84 190E 2.3 black/grey 64K miles (wrecked)
85 190E 2.3 maroon/palomino 92K miles
88 300E desert red/palomino 204k miles
(made to look like a '94-95)
92 400E desert taupe/creme beige 120K miles
(converted to 94-95 E420 looks)

Hi Ross,
no difference for the mounts according to the factory manual.
It thought so, but its been a while since I had a 500E to work on. I dont think there are any on this island. Not to my knowledge anyways.
Good Luck.
F.J.

__________________
F.J.
81 300 SD grey/palomino 168K miles
84 190E 2.3 black/grey 64K miles (wrecked)
85 190E 2.3 maroon/palomino 92K miles
88 300E desert red/palomino 204k miles
(made to look like a '94-95)
92 400E desert taupe/creme beige 120K miles
(converted to 94-95 E420 looks)

Thanks FJ, the car has 172k on her and going strong.

I will have the car looked at soon and have the vibration checked out, I haven't really worried about it too much as it is my built in speed limiter.

I try and DIY when I can and think the engine mounts will be another weekend challenge. Hope those bolts are seized in there, now... where is that portable butane torch???

For future searchers on the subject: F. J. Lahme is right on the money. I have changed mounts on the 6 cylinder W124s and on the W123s and this is certainly much tighter as far as clearance goes and at first seems downright impossible to get these huge mounts out and in. Only variation I noted was that by lifting the engine very high I did not have to remove or loosen the exhaust at all. I did remove a plastic shield at the driver's side subframe near the radiator though for that side. I had also removed the drag link and steering damper beforehand for replacement at the same time which helped with access. Not having to deal with exhaust bolts was great. I worried that lifting the engine so high would possible crack the exhaust somewhere, but so far no issues noted. My high speed (slight rythmic) vibration is now completely gone.

__________________
2008 GL320CDI 6K
1970 280SL 112K
1982 240D 210K (Sold)
1973 220D 220K (Sold)
1967 200D 160K (Sold)
1992 400E 139K (Sold)
1988 300E 148K (Sold)
1987 300D 257K (Sold)
1991 300E 108K (Sold)
1987 300E 131K (Sold)
1978 300D TMU (Sold)
1980 300D TMU (Sold)
MBCA Member

I just finished the 400E motor mount job and thought I'd add my thoughts for posterity's sake. It's a tough job - very tight quarters on the V8 - get out all your tools expect to buy some too. The passenger side wasn't that bad - I took a different approach by removing the oil filter housing. That frees up plenty of space in the front and provides an opportunity to install the redesigned check valve. I still couldn't get the top (mount to bracket) bolt loose so I too removed the bracket and mount together, brought them out towards the front, replaced the mount on the workbench, and reversed the process.

The driver's side is much tougher. I took the exhaust pipe off and still couldn't get the combination mount/bracket out of the engine compartment. So I put the bracket/mount back on the car and went back to trying to break the top bolt loose - finally got it after buying a swivel head rachet and adding a cheater bar. Then the mount alone comes out towards the rear past where the exhaust pipe was. On the driver's side you've pretty much got to figure out how to break the top bolt loose - it's too tight to get the combination bracket/mount out of the engine compartment. It still helps to take the exhaust pipe off - there's just no good access from the front. I had no trouble with the exhaust pipe, even though it was 12 years old. It's a tough project but all doable. Thanks to past contributors - I don't think I would have even tried it without this thread.