[IMG][/IMG]1981 240D has an idle shake or rattle that I am at a loss to figure out. It is only at idle. Anything above idle it goes a way. I changed the engine mount last year thinking that was the issue to no avail. I replaced the idle shock as well as the rubber bushing that mounts behind the oil pan to the chassis cross member, still there. I just noticed that the engine mounts are totally compressed to the point that the metal on the engine mount is touching the frame. I checked the part number 123 241 1213 to see if I got the wrong part and it is the correct part number. I jacked up the engine an inch and can visible see that the engine mount is no longer bottomed out on the frame. The idle rattle is gone. I’m thinking one or two possibilities. 1) a bad batch of rubber from the factory or 2) Trans mount is wrong for the car or installed incorrectly.
Please point me in the right direction. Thanks

Unfortunately there is many directions to go.

What companies Motor Mounts did you use?
The Motor Mounts on my I replaced on my 84 300D were URO which is not a good quality company but the lasted I believe it was 5 years before they collapsed.
People have been using 2 of the same Lemforder (the mounts are made by Phoenix which is the same as the genuine Mercedes mounts. Country of origin is Turkey) mounts for my 300D on the 240Ds of your year instead of the 2 different mounts that only companies like Meyle and so on still make.


Concerning the cause of the shaking at idle it can be caused by one or more the following, uneven compression, unbalanced Injector pop/opening pressure, Injector pop/opening pressure too low, worn our Injector Nozzles, valves not seating or burned, the need for a valve adjustment, idle speed set too low, the overflow/pressure relief valve needs the spring stretched to a free length of 27mm or replaced and that is all I can think of right off.


If your Fuel Supply Lift Pump valves are worn or you are sucking in air.


Some have claimed changing the Delivery valves in the Fuel Injection Pump cured the rough Idle when the other stuff mentioned was not the issue.

__________________
84 300D, 82 Volvo 244Gl Diesel

If idle shake or rattle totally went away when raising engine, cause might be engine mount only.
Mine vibrated badly whenever engine was running but worse in idle when the left engine mount was collapsed. Replaced left mount with a Lemforder for my vehicle and all abnormal engine shake went away. Maybe the 1 yr old mount collapsed early because of oil softened the mount or because it is not a good brand and rubber softened.
In addition, collapsed engine mount caused PS belt to touch the oil cooler hose. Vibration told me to do the repair before something else failed.

Get new mounts, preferably from a dealership.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

I use a guy out of San Diego called Europarts. Though I cannot remember the specific brand, he only sells quality aftermarket and Mercedes genuine parts. In fact I’ve always gotten my motor mounts from him and never had an issue until now. I will give the motor mounts another try I guess.

__________________
1981 240D auto
1977 240D manual 300 Turbo swap
1983 300SD
1983 300TD Parts car

Using 300D Motor Mounts on a 240D (w123 chassis)
Comment from Post #1 between the pictures:
“So after verifying that 300D mounts can be used on 240D cars, I ordered Lemforder mounts from Phil for $26 instead of $134 for OE. I just got them today. Found that they were made in Turkey.”
http://www.peachparts.com/shopforum/diesel-discussion/312703-lemforder-engine-mounts.html#post2882819

As I mentioned on a 84 300D the Lemforder Motor Mounts are the same make as the Dealer mounts except that the Dealer wants a lot more for them. It used to be $22 verses the Dealer $77.

Also I believe if your engine is shaking for other then mount reasons I think it works the Mounts to an early end. The Motor Mounts were made to work along with an engine that is running within specs.

Anyway the Genuine Mercedes Mounts have the Mrecedes Star on them. On the Lemforders the area where the Mercedes star is ground off but the part number and the Phoenix logo are still on the mount.

My Stock Motor Mounts the same as Lemfoerder
http://www.peachparts.com/shopforum/diesel-discussion/305264-stock-84-300d-motor-mounts-same-lemforder%3B-pics-show-proof.html

__________________
84 300D, 82 Volvo 244Gl Diesel