I've done this job a couple of times on W123's, and many times on various other vehicles. I don't think that I'd want to try it with the vehicle out of level. I don't see any reason to have the front up, other than to ease removal of the engine stop. In any case, I would never get under a car on ramps without having the other pair of wheels chocked.

I'd expect up to three inches of lift before the engine starts to move. I'd stop when I see the tires leave the floor. Perhaps your front springs are sagging badly. Not to suggest that you've made an error, but are you sure that you got the bearer bolts out? If you rock the engine, then you should see it moving free from the mounts, or at least see the shields wiggling around some.

__________________
'79 240D

Well I had to put the front tires up on (low-level) ramps because otherwise there wasn't enough space for me to get under the car to remove the two engine bearer bolts. But no need to put it on ramps now that the engine bearer bolts have been removed. I'll try again tomorrow morning with the car level on ground and will attempt lifting the engine up higher, as you suggested.

But to lift the engine up via the oil pan...wouldn't it too much stress on the oil pan (collapsing it) if I were to lift the car up until the tires left the floor?

Yes believe me, I got the two engine bearer bolts out...they are two M10 bolts which I removed with an 8mm hex socket that go right into the side mounts from below.

And no, I've tried to rock the engine by pushing hard on the valve cover, but it is stuck, it does not move at all. Should I be concerned at this point, or just go ahead and raise the engine more tomorrow as you said?

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

I questioned whether you'd actually gotten the lower bolts out because I didn't find it necessary to raise the car to access those bolts, but working from memory I can't picture any other 10mm bolts in recesses that you could have removed down there.

I'm half joking here. I would not attempt to raise the tires off the floor by jacking under the oil pan. I'd bet that the pan can take the stress, but it wouldn't be very gentlemanly for me to make that bet with your car. I would go up almost that far--to the point where some of the weight is off the wheels. At that point you should at least get the engine to rock fairly easily. You mentioned the possibility of there being engine shocks installed. You're correct in assuming that there shouldn't be-- but since your front engine stop is missing, things may have been done to this car that shouldn't have been done. If an engine shock was installed, it should be attached to the drivers side engine bearer. You can tell at a glance.

Other than that remote possibility of an improperly installed engine shock, there is nothing other than gravity holding down the engine if the lower bolts are out. The engine will lift. If not, I have no explanation.

I would. I'd also locate the missing parts for mounting the front stop and install it, as well as replace the rear stop. Since you've already bought it, you might as well put it in.

__________________
'79 240D

Thanks Left Coast I will look to see whether there is an engine shock installed on either side and then try again to lift the engine, this time pushing it a bit higher, and see what happens.

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

when I did my mounts I had that "why is the whole car going up, and not just the engine" moment, but just kept jacking, I think if you jack a little more the engine will separate from the rest of the car.

make sure the piece of 2x4 under the oil pan is large enough to disperse the weight along the whole width of the pan

You were right, it worked just fine by raising more the engine.
By the way, there were no engine shocks installed on my car.

Here you can see a couple of pictures of the old side mounts
(sorry, I realized the pictures were so dark only after the
old mounts were thrown away):





The one on the left (in both pictures) is the passenger side mount.
You can see how it completely collapsed.
Because of it, the engine was about one and a half inches lower
on the passenger side than on the driver side, and it had also
drifted about one and a half inches in that direction, thus
pinching that line as shown in the first picture in this thread.
Possibly as a result of it, when lifting the engine by raising the oil pan,
the engine bearer on the driver side came up much more than
the one on the passenger side. That way it was going to hit the
return hose to power steering system right were it attaches
to the connection at the power steering box. So I had to disconnect
that return hose, drawing first the ATF out of the power steering
pump reservoir, as per FSM 00-211 instructions (now I have to
refill the power steering system with PS fluid as a good amount of
the old ATF ended up on my garage floor... and will have
to bleed the system too..). Also as the engine went up, the fuel
line to fuel filter got fully extended and ultimately disconnected,
also spilling some fuel on the floor I later had to use the fuel
hand pump to bleed the fuel system.

I found that the passenger side mount was missing one of the two
screws, so I now do need one. I also need the front mount (AKA
engine stop, AKA t-mount) assembly, which is not currently
installed on my car....meaning the upper and lower straps and the
four M8 bolts (my car still has the adjusting screw installed).
So, if anyone has an extra side mount screw, or the front mount
assembly, and is willing to sell them to me, that would be great.


To sum up the procedure I went through for replacing the side
mounts, hoping it will be useful to someone reading this, these
are the steps I took (which, unfortunately, not even the FSM lists
fully). Keep in mind that I did not have to loosen and adjust the
engine stop, which is part of the procedure if you have it on your
car, because I don't have one currently installed. Also my car did
not come with engine shock absorbers. If you have a 240D with the
automatic transmission, you probably have one and must unscrew
the engine shock's lower nut while securing the piston rod so that
it doesn't turn, BEFORE lifting the engine.

Tools I Used for the Job:

- 10 mm socket (to remove air filter assembly)
- Small screwdriver, to remove dirt from the hex heads before
attempting to unscrew them
- A good 8 mm hex socket (engine bearer bolts at side engine mounts,
which are removed from below the car)
- Adjustable wrench (to disconnect/reconnect return hose to
power steering system)
- Medium size blade screwdriver to disconnect/reconnect the fuel line.
- A good 6 mm hex socket (screws on side mounts, removed from
above)
- 13 mm wrench to release adjusting screw on rear (transmission)
mount in order to more easily align engine bearer tips on mounts.
- 3/8" ratchet with short and medium extenders
- 22 mm wrench to release bolt over fuel filter in order to bleed the fuel
system (since my fuel line to fuel filter was disconnected)


Step by Step Procedure I used for Removing Side Mounts on my 1979
240D, manual transmission:

a) Remove air filter assembly, in order to access passenger side
mount
b) Disconnect radiator shroud (or radiator fan will hit it when
you raise the engine)
c) Disconnect accelerator linkage (just the last link to the
chassis)
d) Use a small screwdriver to clean out hex heads. The hex bits
must go all the way in and fit properly, otherwise the heads
will strip.

1) Unscrew engine bearer bolts at engine mount, working from
below. In my case these were M10 x 40 bolts, one per mount.
2) If you have power steering, you will probably have to
disconnect return hose to power steering system. Before
doing so, draw fluid out of power steering pump reservoir.
At least watch out for that hose while lifting the engine,
you don't want the engine bearer to hit it.
3) Raise the engine, applying jack to oil pan. Make sure to
insert a large block of wood between jack and oil pan to
avoid damage to oil pan. At first both the chassis and the
engine will rise together because the springs will push
up the frame as you are lifting the engine. In my case,
both the chassis and the engine rose together about 5"
before the engine started lifting from the chassis.
While doing this step, keep an eye on the power steering
pump hose (if you haven't disconnected it) and the fuel line
to fuel filter (which may get fully extended e disconnect,
depending on how much you will have to raise the engine
to get clearance on both sides). Before this step, you
should have disconnected both radiator shroud and
accelerator linkage.
4) Withdraw mount shields.
5) Remove mount screws and pull out old engine mounts.
6) Put in new side engine mounts and put back screws. In my case,
the engine rose more on the driver side, so I installed passenger
side mount first by pushing on the valve cover toward driver side
so as to raise a bit more passenger side's end of the engine and
slide passenger mount in.
7) Reinsert mount shields.
8) Fully release adjusting screw on rear engine (transmission) mount in
order to more easily align the threads in the engine bearer tips with
the holes in the chassis so that you can later reinsert and tighten the
engine bearer bolts.
9) Lower the engine very slowly, making sure the engine bearer tips go
right into the center of the mounts. You may have to use a pry bar (I
used one with a flat, bent tip) leveraging between the mount's top
and the engine bearer tip while rocking the engine (hand on valve
cover) back and forth in order to properly align those engine bearer
tips. It may take several attempts and a lot of time...this is especially
true if one or both of the old mounts were damaged/collapsed and
consequently the engine has been sitting in an inclined position for
a while. If needed, you can also use a smaller pry bar or large
screwdriver from below, through the chassis holes, to push laterally on
the engine bearer bolts' heads once the latter have been inserted
and screwed in most of the way, if you still need to move the engine
slightly for better alignment on both sides. I had to do this too.
10) Once you are satisfied that the engine bearer tips are
positioned in the center of the mounts and that holes and threads
are properly aligned, reinsert M10x40 hex head bolts from under the
car and torque to 40 Nm.
11) Remember to tighten up adjusting screw on rear (transmission)
mount.
12) Put back whatever you disconnected/removed in the previous
steps.
13) If fuel line and return hose to power steering system were
disconnected, you will need to bleed fuel system and replenish PS
fluid and then bleed PS system.

And, finally, enjoy it! Which is the most important part of what we do
while taking care of our old, wonderful, beloved cars!


Happy Thanksgiving to You All!

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

when you put that t-mount in, don't forget to add more of those very detailed instructions. Thanks in advance...

Will do

I am waiting till I can find/buy the missing t-mount assembly somewhere.

I'll soon also replace the rear engine (transmission) mount and add the installation steps to this thread.

Does anyone have an extra side mount (top) screw or a t-mount assembly to sell me? (I'm in Los Angeles.)

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

I drove the car this morning and I have to say I am very pleased.

No more vibrations all over the place and, as an added benefit, the new mounts seem to have slowed down the idle speed, which was too fast, by repositioning the engine. The engine sounds wonderful now, as it should...and you cannot see the engine vibrate at all...





Compare the previous picture (top) with the new one: it will give you an idea of how much the collapsed passenger side mount had caused the engine to move down and to the side. There were a few strange noises coming from under the hood before with the engine running...but they are all gone now...

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

Just replaced my t-mount yesterday. It is pretty straight forward...

1. Raise vehicle or use ramps as I did
2. For the two small nuts use a 13mm wrench to hold the bolt while using a 13mm socket/ratchet to take off the nut.
3. For the big bottom bolt, There is a "keeper" holding the head of the bolt so it does not back out, Just lift and pivot out of the way.
4. Use a 19mm wrench to back out the large bolt from the plate it is threaded into. (Mine required a few strikes from a deadblow hammer on the wrench to get the bolt to back out)
5. When the large bolt has backed off the plate enough, remove plate, clean everything up, replace mount, and nuts and your done! very easy!

I just did mine and cut two 10" X 13" pieces of 3/4" plywood to fit the oil pan. Lifted the car using a hydraulic jack and placed the front tires on steel ramps. Then removed the radiator shroud clips, air cleaner and upper radiator hose along with the throttle linkage at the firewall. Loosened the 8mm motor mount bolts using a 1/2" drive socket then lifted the engine by placing the two 10"X13" pieces of 3/4" plywood under the oil pan. The 10" X 13" size worked well to disperse the pressure exerted by the floor jack. Once lifted, I placed a 6" 2X4 piece of wood under the bell housing of the transmission supported by a jack stand (just in case the hydraulic floor jack failed). Then removed the air cleaner to allow easier access to the passenger side mount. After this, motor mount removal/install was easy.

To adjust the t-mount properly, you will have to first release adjusting screws at both t-mount (aka engine stop) and rear engine mount. Then slightly rock engine from side to side with your hands, and later use the special tool (you can build it or something similar yourself easily by following directions in the FSM - see suggested links below) to properly position the t-mount. Finally, having done the above, you can tighten adjusting screws at both t-mount and rear engine mount. Lastly, withdraw the special tool from t-mount. At this point you will have a functional, properly adjusted t-mount.

It's easily done if you look at the drawings when reading the instructions. You can download the two FSM (with drawings) relative to this job here:

00-215 Removal and installation of front engine stop:
http://www.google.com/url?sa=t&rct=j&q=00-215+%22engine+stop%22&source=web&cd=1&ved=0CC4QFjAA&url=http%3A%2F%2Fwww.tglmarketinginc.com%2Fmbforum%2Fservman%2FMB%2520Service%2520Manuals%2Fwww.paul drayton.com%2Fuploadfiles%2Fmerc%2FService%2FW123%2Fw123CD2%2FProgram%2FEngine%2F615%2F00-215.pdf&ei=Na3WTqbMMe7JiQL28LTlCQ&usg=AFQjCNFlyfQRK5zUcMm-B7iLDvdabR4WuA

00-220 Adjustment of engine stop:
http://www.google.com/url?sa=t&rct=j&q=00-220+%22engine+stop%22&source=web&cd=1&ved=0CC4QFjAA&url=http%3A%2F%2Fwww.tglmarketinginc.com%2Fmbforum%2Fservman%2FMB%2520Service%2520Manuals%2Fwww.paul drayton.com%2Fuploadfiles%2Fmerc%2FService%2FW123%2Fw123CD2%2FProgram%2FEngine%2F615%2F00-220.pdf&ei=NazWTtjfOejViALWhfDGCQ&usg=AFQjCNErDxhOo74UcYsJ2mcTpGlHXkLeOw

I hope it helps.

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

The car will naturally come up some, not because you're lifting the whole car, but because you're taking the weight of the engine off the springs.

__________________
1981 Mercedes 300TD, 1994 Honda Civic Del Sol
http://mefi.us/images/fuelly/smallsig-us/67195.pnghttp://mefi.us/images/fuelly/smallsig-us/103885.png

I finally got to replace my transmission mount today.

Tools needed for this job: 19mm wrench, 13mm wrench, 17mm socket, 13mm socket, 6mm hex key, 3/8" ratchet with short extension.

First of all, there was an old, alien transmission mount installed, nothing like it should have been on this 123.123 240D. You can see it on the left, in the (bad) picture below, compared to the brand new mount which went in, on the right.



The old mount has a strange enough 1" x 3/4" square tubing in the place of the round pipe that is proper for my car. This old mount doesn't look like any of the four mounts illustrated in FSM 00-212 (Removal and installation of rear engine mount) meant for type 115.1 and type 123.1 MB's. I have no idea why it was there, it shouldn't have been. It very likely contributed to the old vibrations.

Also, perhaps the engine bearer currently installed on my car is not the proper type, as the new mount (No. 123 240 20 18, which is the proper one for my car - meant for chassis above 050513 with manual transmission) had a round pipe which was way too long to fit into the engine bearer.
Therefore, I cut an 8mm length off it:



and after that it fit into the engine bearer just fine.

The removal/installation procedure is very straightforward (I did not have a front engine stop to preliminarily release the adjusting screw of, which would normally be the first step of this procedure, since I don't have one on my car yet, still waiting to find an assembly for it somewhere...my car came without one when I bought it 7 years ago):

1) Unscrew 19mm nut attaching the top of the old mount to the frame.
2) Release adjusting screw (using a 13mm wrench in conjunction with a 6mm hex key)
3) Unscrew the two bolts from below (13mm socket) that attach old mount to engine bearer.
4) Since I have a manual transmission, at this point I simply supported the transmission by use of a jack.
5) Unscrew the two large bolts (17mm socket) and pull out engine bearer.
6) Remove old mount from engine bearer and place new mount in, making sure you insert adjusting screw WITHOUT TIGHTENING IT, and use the two bolts to attach mount to engine bearer WITHOUT TIGHTENING THEM. Make sure you place the mount in the engine bearer facing the right direction: compare it to the upper frame where it will be bolted to and you will promptly understand that there is a right way to put it in.
7) Screw back engine bearer to frame using the two large bolts WITHOUT TIGHTENING THEM.
8) Lower and take out of the way jack that was supporting transmission.
9) Tighten engine bearer. Do not use a breaker bar, even though these are big bolts. Proper torque here is only 30 Nm!
10) Tighten bolts attaching mount to engine bearer (also at 30 Nm).
11) Tighten adjusting screw (40 Nm).
12) Finally, screw 19mm nut on (70 Nm).

Done!

With the two new side mounts, this new transmission mount and the four new bilstein shocks I installed recently, the car now rides like a new Mercedes! Even though it is still missing a front engine mount (engine stop).

__________________
1979 240D, W123, 105K miles, stick, white w/ tan interior.

The springs may take more to unload than your current 2-3 inch lift is. You are lifting most of the engine weight off them remember. That engine if fairly heavy for a four banger as well. Take a look at your new mounts for the fastenings. If you have removed what obviously is indicated on them lift the engine higher.

I have seen the exhaust header pipe bolts loosened to do this as well. Do not know if it is a neccesity on this model. It would not totally prevent some mount separation from the chassis anyway.