bha1

Has anyone replaced the engine/trans mounts on their car? Was it difficult?

I have lots of tools but no hoist. Have done the trans mount on my R230 and it was pretty easy. The S550 looks identical but the 4matic version (which I have) has a slightly different mount. A few more bolts but looks like basically teh same procedure.

Have never done motor mounts but I have a shop jack, wood block, etc. Set of high ramps, etc. So should be OK for tools.

But how difficult are the motor mounts? I saw someone said they had trouble getting to the top bolt without a special wrench. WIS calls for a special wrench set but they do that a lot and it just means you need a crowsfoot wrench or something (nothing exotic)

Has anyone actually done these and can explain if it was hard?

I see the book time for 2 motor mounts on a 4matic is 2.3 hours. Seems pretty long as I would have assumed a pair of motor mounts without any complexity would take about an hour or so?

I may purchase all 3 mounts, replace the Trans myself (as I'm 80% sure that will fix my problem) If that doesn't fix the problem, I'll take the 2 motor mounts and have my local indy shop do them (and pay the 2hrs labour charge).

Em Bee Lover

My indie did all three mounts for me. Trans was pretty direct. One of the engine mounts apparently is a sob to get to. He is very experienced and proficient. For him to take as long as he did says the job is not a walk in the park, plus he doesn't fluff hours/billing. My two cents.

bha1

That's what I figured..

I think I'll do the trans mount and see if it fixes the problem. If not, I'll drop the car at the indy shop near me with 2 engine mounts and let him do those.

If it is truly a pain in the butt to do those, I'd rather he do it (he's very experienced with these cars and knows this stuff off the top of his head). Besides, 2hrs labour charge is totally reasonable if I can just drop off the car and pick it up at the end of the day.

MagCL

I changed all three of mine but if your indy will charge you only 2 hours, then let him do it. The left mount is a nightmare to remove and you will definitely need the special wrench. The tranny mount is simple to change. I would also recommend buying new bolts for the front two mounts. One of mine broke while I was removing it.

bha1

I don't know that he'll charge me 2 hours, but assumed that from the book time (I beleive it said 2.3 hours for both).

Trans mount looks easy.. how long did it take you to change the engine mounts? I will buy the special tool and a set of new bolts.

Do you have a part # for the tool, or where did you buy it? And if you don't need it anymore, I'm in Oakville and will buy it from you.

Thanks!

bha1

Looked at the WIS instructions and I'm gonna give this a shot, after buying the 'offset wrench' as posted above. It looks like a bit of a challenge actually

If I'm going to get dirty and underneath the car for the tranny mount, I might as well give the engine mounts a shot while I have the tools out and car jacked up.

Welwynnick

The tranny mount is easy, but engine mounts are an order of magnitude more difficult.

Its DIY-feasible, but only for experienced folks. I changed mine last week, and I'd recommend you consider dropping the subframe to get access. The usual way is to remove the exhaust and the steering rack, but that's rather a pain. Mine is RWD though - do your front drive shafts feed through holes in the subframe?

Nick

bha1

Nick,

Do you have a W221? Your signature shows a 2004 S600 which would be a W220. I ask because your description is a little different from what is in WIS. They say nothing about removing the steering rack (other than detaching one part of it) and removing the exhaust.

bha1

For reference, here are the WIS instructions for the engine mounts. I put in my VIN number (my car is a 4MATIC) and this is what came up. Based on the title, it appears the directions are for 4Matic cars, so those of you with RWD would have had different steps to follow.

This doesn't look too difficult.. assuming I have the special wrench (which I just ordered) and new bolts, I don't see anything too difficult at all. There is a line that must be removed along with a bracket (power steering) and also the steering shaft has to be disconnected. But the rest looks pretty standard.

For those of you who have done this job, are these pretty similar to the directions you followed? What part was really difficult other than reaching that one engine mount bolt?

---

1 Remove ground line(s) from battery AR54.10-P-0003SX
(batteries)
2 Move front wheels to straight-ahead position The steering wheel must not be turned
and secure steering wheel. when the steering coupling is detached,
otherwise the clock spring contact will be
destroyed.
*129589012100
3 Remove air filter housing AR09.10-P-1150SX
4 Remove heat shields from engine mounts (8)
5 Remove bolts (5, 7) *001589011600
*BA22.10-P-1001-03D
*BA22.10-P-1002-03D
*BA22.10-P-1001-03C
*BA22.10-P-1002-03C
6 Attach engine hoist and raise engine No not apply tension to or damage lines AR33.10-P-0105SX
or hoses.
Attach shackle to front engine
suspension lug only.
7 Remove bottom engine compartment AR61.20-P-1105SX
paneling
8 Detach steering coupling at steering shaft AR46.10-P-8000SX
9 Remove left engine mount (8) to the rear Installation: Align anti-twist lock on
and down engine mount (8) to cutout on engine
support (6).
10 Detach power steering oil line (4) from
holder (2)
11 Remove holder (2) from alternator (G2) by *BA15.40-P-1001-01F
removing bolts (1)
12 Remove right engine mount (8) to the front Remove engine mount (8) between front
and down axle carrier (9) and fan shroud.
Installation: Align anti-twist lock on
engine mount (8) to cutout on engine
support (6).

Welwynnick

Sorry, ignore what I said, the W221 and W220 subframes are quite different. Go with WIS.

Nick

bha

Did the job yesterday (at least most of it) and it was difficult.

I did buy the special wrench. It's not a 'nice to have' kind of thing.. it's TOTALLY required. You won't get the top bolt out without it.

For the two lower bolts, one is easy to get to and the other is hard. You'll try to use a flexible extension on it, wobble extension, and just a socket wrench. It wont come out with any of these.

Use a long socket (mine was about 1.5 to 2" long) and a 3/8" socket wrench. That will get it out. Any other wrench will be too short or too long and hit the exhaust manifold. You can't reach it with a long extension because the exhaust is in the way.

Got all of these bolts out and the engine jacked up. Now comes the REALLY hard part.

The drivers side mount has to go back, then down. You slide it along and downward to get it out. Here's the secret.. it comes out in the hole in the THIRD underbody panel not the second. First panel is under the bumper, 2nd under the engine, 3rd under the transmission.

You need to remove the mount all the way back in the hole in the 3rd panel. Right next to one of the cat converters. No other way to get it out. Don't try to get it out of the 2nd panel because it won't come out! I did remove all the panels by the way.. just describing the area where the panels "would" be if installed.

You also need to remove the steering coupler. One bolt/nut at the bottom, and one bolt at the top. Look and you'll see what I mean. You can't put it back on at an angle or the wrong way but PLEASE make sure the bolts are on tight with a dab of locktite. You don't want this thing coming off WIS says if the steering wheel is moved while this is disconnected, you'll destroy the clock spring instantly. So I didn't touch the wheel at all.. didn't even open the car door while this piece was disconnected. Put the top (closest to the steering wheel end) back on first, not the bottom . Or you'll never get the top on.

Trans mount is really easy once you've done an engine mount. 15 mins max.

Passenger side engine mount is IMPOSSIBLE. Got it unbolted, and raised the engine as high as it would go (even tried it with the other mount unbolted too) and could not get the mount out. It says it goes toward the front of the car, then comes out between the subframe beam and the fan shroud. I couldn't get it to move more than an inch or two to the front of the car. It wedges between the engine (exhaust manifold) and the body of the car. If the mount were 2" smaller then maybe it would come out. But no way was this thing coming out.

Put the whole thing back together an the vibration is mostly gone.

Maybe I'm reading the date codes wrong, but the trans mount was dated 2012 and was an original MB part wth a part # on it. Same with the engine mount but it said 2013. Which is weird. I just bought the car so will have to check with the previous owner if he did them.

I can't seem to find any way to look up the old (bad) style of engine mounts and the new (revised) ones because they all have the same part number. Even the MB bulletin that says to replace them due to vibration says "replace with new revised part # xxx xxx xxx xx" but that's the same part # as the old ones. So not sure whether I had the old or new style.

In any case, the vibe is mostly gone. Don't know whether it was transmission or engine, but I suspect trans because I only have 1 new engine mount in.

Anyhow, if you're gonna do this at home, make sure to get the special wrench off eBay/Amazon. And do the drivers side first. If that goes well, do the passenger but don't spend more than an hour on it... if it won't come out have a shop install it.

Don't pay anyone to do your trans mount. I have a 4matic and it's simple. I remember my non-4matic car (R230 with same style of mount as the W221 non-4matics) was even easier.

Nickthegreek

[QUOTE=bha;6037094]Did the job yesterday (at least most of it) and it was difficult.

I did buy the special wrench. It's not a 'nice to have' kind of thing.. it's TOTALLY required. You won't get the top bolt out without it.

For the two lower bolts, one is easy to get to and the other is hard. You'll try to use a flexible extension on it, wobble extension, and just a socket wrench. It wont come out with any of these.

Use a long socket (mine was about 1.5 to 2" long) and a 3/8" socket wrench. That will get it out. Any other wrench will be too short or too long and hit the exhaust manifold. You can't reach it with a long extension because the exhaust is in the way.

Got all of these bolts out and the engine jacked up. Now comes the REALLY hard part.

The drivers side mount has to go back, then down. You slide it along and downward to get it out. Here's the secret.. it comes out in the hole in the THIRD underbody panel not the second. First panel is under the bumper, 2nd under the engine, 3rd under the transmission.

You need to remove the mount all the way back in the hole in the 3rd panel. Right next to one of the cat converters. No other way to get it out. Don't try to get it out of the 2nd panel because it won't come out! I did remove all the panels by the way.. just describing the area where the panels "would" be if installed.

You also need to remove the steering coupler. One bolt/nut at the bottom, and one bolt at the top. Look and you'll see what I mean. You can't put it back on at an angle or the wrong way but PLEASE make sure the bolts are on tight with a dab of locktite. You don't want this thing coming off WIS says if the steering wheel is moved while this is disconnected, you'll destroy the clock spring instantly. So I didn't touch the wheel at all.. didn't even open the car door while this piece was disconnected. Put the top (closest to the steering wheel end) back on first, not the bottom . Or you'll never get the top on.

Trans mount is really easy once you've done an engine mount. 15 mins max.

Passenger side engine mount is IMPOSSIBLE. Got it unbolted, and raised the engine as high as it would go (even tried it with the other mount unbolted too) and could not get the mount out. It says it goes toward the front of the car, then comes out between the subframe beam and the fan shroud. I couldn't get it to move more than an inch or two to the front of the car. It wedges between the engine (exhaust manifold) and the body of the car. If the mount were 2" smaller then maybe it would come out. But no way was this thing coming out.

Put the whole thing back together an the vibration is mostly gone.

Maybe I'm reading the date codes wrong, but the trans mount was dated 2012 and was an original MB part wth a part # on it. Same with the engine mount but it said 2013. Which is weird. I just bought the car so will have to check with the previous owner if he did them.

I can't seem to find any way to look up the old (bad) style of engine mounts and the new (revised) ones because they all have the same part number. Even the MB bulletin that says to replace them due to vibration says "replace with new revised part # xxx xxx xxx xx" but that's the same part # as the old ones. So not sure whether I had the old or new style.

In any case, the vibe is mostly gone. Don't know whether it was transmission or engine, but I suspect trans because I only have 1 new engine mount in.

Anyhow, if you're gonna do this at home, make sure to get the special wrench off eBay/Amazon. And do the drivers side first. If that goes well, do the passenger but don't spend more than an hour on it... if it won't come out have a shop install it.

Don't pay anyone to do your trans mount. I have a 4matic and it's simple. I remember my non-4matic car (R230 with same style of mount as the W221 non-4matics) was even

One of the mechanics at my local dealership told me theres a much more direct way to do this. He removes the engine fan to make more room. Remove the bolts on the mounts. Then raise the engine until the axleshafts touch the subframe. Loosen/remove the bolts on the alternator and ac compressor. Then you snake them out

bha

Wow that sounds interesting. I followed the WIS directions figuring it was safest but maybe the MB techs do so many of these they have 'improved' on how to do them.

I'm not going to try it though.. removing the fan sounds fine but when I raised my engine I got nervous lifting it even a few inches. It seemed to have more resistance (maybe the rubber in the mounts was twisting, etc.) but I just couldnt get the thought out of my head that I was bending the driveshaft/exhaust/AC lines/etc.

There are too many expensive parts for me to break/bend that I'd be worried to try this unless I was an MB tech who has done a lot of them (which I'm not...)

I am undecided between dropping the mount off at my indy shop and having them do it (just one mount left.. I was able to do the other two). And the other option is to unbolt the one mount, jack it up really high and play with it for 1/2 hour till I get it out. It might end up being a waste of 2hrs if I can't get it and have to put it back together again though....

Nickthegreek

Yeah he told me the dealerships always love a faster way to do sonething because it means more cars in and out of thr bays hence more money. The whole taking apart the steering column sounds unneeded. I dropped the sunframe when I had a w211. Not fun but got the job done pretty quick

Nickthegreek

Hey everyone,

I just got done changing my motor mounts last night and it wasnt bad at all. Did it in under 2 hours. I didnt need to take out the alternator or ac compressor or the cats. I just took the engine hoist and moved it over to one side which forced the engine over and then pried between the frame and timing case. It was a tight fit but nothimg impossible. On the drivers side it popped out where the evap purge solenoid and low ac line are, you just need to push them over alittle. On the passenger side it came right out behind the alternator. Now what as a complete ***** was getting the heat shields out to make room for the top bolt. That took alot of contorting to reach that back bolt. I left that bolt out. Not even worth putting it back in. You need an assortment of extensions and u joints. Also i have two special wrenches i bought from sears ill post. Nothing too expensive. Its totally doable but you have to have patience and be ready to be in some weird contorted positions to get at the back bolt of the heat shield. Also you only need to hook the hoist to the front loop. At first the whole car lifted and i thought the hoist was doing it,but it was because the springs were unloading and the car stopped lifting at a certain point and then just the engine lifted until the front axles hit the subframe. I have 4matic.

Nickthegreek

Heres the wrench for the top mount bolt. On sale at sears 40% off a whole set

Nickthegreek

Heres a comparison of an old and a new mount. The metal portion is identical but if you look inside, the new one on the left has rubber that sits flush with the top metal flange, while the right one has sunken in about a half inch. I was feeling all kinds of vibrations and now they are gone

BenzV12

You must be a handy person great job
Super informative post thanks for that

bha

Now you're making it sound easy, and starting to make me doubt my abilities

So tell me more about the passenger side one.. because your email has convinced me to try that one last mount again.

You say towards the alternator.. which is towards the front of the car. Once you get the mount to the alternator, does it go up (towards the hood opening) or down (towards the floor)?

I was using a shop jack and maybe didn't get that side high enough because I was lifting the entire oil pan. I even tried it with both mounts unbolted but was afraid to jack it higher. Would you say the engine crane was required to get the engine high enough? How high did you lift the passenger side of the engine?

The bolts are easy for me.. I bought the special wrench from ebay shown earlier in this thread, and the bolts came out very very easily. I can't see how it could be done without either the wrench you bought, or the one I bought. You can't remove these with a regular socket set, for anyone who is thinking of trying it!

I'm convinced I'm going to rent an engine crane, pop the right side bolts out, and figure out how to get that mount out. It's bugging me now!

By the way, my mounts looked brand new (although they were dirty) but replacing the drivers side and the trans mount fixed most of the problem. It's still there so I have to replace the passenger side still.

Nickthegreek

Yeah i would say an engine crane is needed. With a crane you can move the engine from side to side. With a jack you cant because you might knock the engine off the jack. I jacked the engine up about 2 inches maybe. knock the mount over and it'll fall into the frame. then i got a coat hanger and grabbed it with it and then got a 4 foot breaker bar and pushed the engine over and had the hoist over to one side to assist. Then I snaked it up vertically behind the alternator. you have to play around with twisting it and itll pop right out. youll also have to remove the bottom two bolts from the drivers side again so it will lift evenly and move sideways for you

Nickthegreek

oh and when you lift the engine up look at the axles and lift it until they are just barely going to touch the subframe. If you put alot of tension on them the engine wont move from side to side so easily. essentially that way it will be free floating

Nickthegreek

No problem anything to inform people more

bha

OK this helps a lot. I will borrow/rent a crane to do the passenger side mount. A few questions just to confirm things:
-So it sounds like you moved the mount "forward" since you say towards the alternator. As opposed to "backwards" towards the rear of the car. Is that correct?
-When you say "had the hoist over to one side to assist" what do you mean? The chain the engine was hanging on was vertical, then you pushed the crane over so the chain wasn't vertical any more (it would be at an angle)?

Thanks!

Nickthegreek

correct you push the crane over to one side so that the chain is at an angle. what this does is it moves the engine with it over to one side and lifts that side up just a bit as well to give you room. And then when you pry against the frame/timing cover you wont need to put too much force on it because the crane is doing the majority of the work already. And you wont be fight against the crane either

and you move the mount towards the front of the vehicle and pull it out vertically just behind the alternator

Nickthegreek

Any luck yet?