1985 300D Motor mount madness!!! - PeachParts Mercedes-Benz Forum

#1 02-23-2009, 07:10 AM

Hi guys need some help here. Trying to change motor mounts on 85 300D and have a lot of questions. So here goes. 1. How do I take the engine shocks out? I have undone the top nut but do I need to undo the bottom one as well or can I get away with just the top one? 2. Where is the bolt that holds the motor onto the cross member? I can't seem to find it but in the DIY article it says you need to undo it. And LAST 3. The drivers side motor mount the rear 6mm bolt (one closest to the engine) is below/hidden/underneath the engine shock/engine fork thing (the part that goes in the center or the motor mount that is attached to the engine). Help me Obi wan kinobi you're my only hope!!! This is driving me crazy.

#2 02-23-2009, 07:40 AM

Anyone anyone at all? help

JimmyL · #3 02-23-2009, 08:05 AM

Quote:

Originally Posted by helpplease

Help me Obi wan kinobi you're my only hope!!! This is driving me crazy.

Patience young Luke!

There are photo'd procedures on here somewhere if you search.
Cliff notes version:
Loosen 8mm allen screw on the bottom of the engine mount, under car. [makes sure and clean grime from inside allen so as not to strip]
Loosen "bottom" of engine shock. 10mm nut on bottom, and you'll have to use a very small wrench to hold the shock shaft at the bottom most area of the shock shaft. 6 or 7mm wrench I believe. A nut, washer and rubber grommet will come off.
Unhook accelerator linkage to injection pump. [the one that comes from the firewall so it doesn't bend when you jack up the engine]
Some folks only do one side at a time, others loosen both engine mount bolts at the same time. YRMV
Place a piece of wood [at least a 2x4] under the oil pan and jack engine up. It will jack up quite a bit, 4-6 inches. Listen for unpleasant noised but you should be fine.
Then you need to loosen the 6mm allen bolts from the top. The bolt you speak of can be harder to get to than the others, but with engine jacked up you can finally get to it.
Replace mount, with shield on top of it if still there.
Lower engine, making sure the engine shocks drop through the holes they are supposed to. Can be tricky.
You also have to line up the hole in the engine arms with the hole up through the engine mount. Sometimes a prybar will be necessary to center engine.
NOTE:
You do NOT want to cross thread these 8mm bolts. If you can't get it easily started don't tighten it up!
Reconnect everything. Enjoy!

Try to have more patience in the future. Still early in the morning, especially for the west coast folks.
A search would have given you the info almost immediately, with pics.......

#4 02-23-2009, 09:52 AM

Thanks Jimmy Sorry for the early post but was a crap weekend....been working on this thing since saturday with no sucess.

winmutt · #5 02-23-2009, 09:59 AM

Well did you get it fixed?

#6 02-23-2009, 10:13 AM

Fixed this weekend no...internet was down, couldn't find my Haynes manual (not that those are all those valuable), and my wife washed the instructions I had pre printed on the internet. I will hopefully get it fixed tonight or tommorrow night will post with the postitive results. My spelling is horrid.

tangofox007 · #7 02-23-2009, 10:40 AM

Quote:

Originally Posted by helpplease

couldn't find my Haynes manual (not that those are all those valuable),

Don't use the torque value (130 Nm) that Haynes provides for the mount-to-frame bolt. It's way too high and will likely result in stripped threads in the support arm. The MB 618.95 engine manual calls for 70Nm.

#8 02-23-2009, 10:44 AM

Tango still can't find the haynes manual...when I get the car fixed tonight or tomorrow I am sure I will be tripping over the darn thing every 5 minutes.

#9 02-24-2009, 07:03 AM

Well I can't seem to get the motor shocks to unbolt I have put the vice grips on them and the 10mm nut doesn't move, Now the problem is the vice grips have messed up the threads. So any ideas as to how I can proceed?

JimmyL · #10 02-24-2009, 09:46 AM

Quote:

Originally Posted by helpplease

Well I can't seem to get the motor shocks to unbolt I have put the vice grips on them and the 10mm nut doesn't move, Now the problem is the vice grips have messed up the threads. So any ideas as to how I can proceed?

You should have read and headed the part about using a wrench to hold the shaft of the engine shock. Or did that get washed too.......

[OK, mild jab there]
Hopefully you can still get a wrench on that lower part. If not, your job might have gotten a bit tougher.......

tangofox007 · #11 02-24-2009, 09:52 AM

Quote:

Originally Posted by JimmyL

Hopefully you can still get a wrench on that lower part. If not, your job might have gotten a bit tougher.......

And more expensive. Those shocks aren't cheap.

Leverage is a great ally. Try a longer wrench.

#12 02-24-2009, 09:55 AM

You should have read and headed the part about using a wrench to hold the shaft of the engine shock (how? A wrench to hold which part?)

::matthew · #13 02-24-2009, 10:12 AM

FSM - Engine Mount

FSM - Engine Shock

tangofox007 · #14 02-24-2009, 10:35 AM

Quote:

Originally Posted by helpplease

You should have read and headed the part about using a wrench to hold the shaft of the engine shock (how? A wrench to hold which part?)

There should be a 7mm wrench flat on the lower shock strut rod, just above the rubber mount.

See the very end of the second link posted by ::matthew.

#15 02-24-2009, 11:07 AM

At this point in time I really wish I would have just taken it somewhere and had this done. I am now going to be around the same amount of money as having a shop do it. CRAP!!!!!!!!