Blow-by

Is there oil puddled in the bottom of the air filter pan. If not dont worry about it. Oily and sooty air filters are not uncommom

Do NOT get talked into engine work because of an oily air filter element. My '80 300SD had this problem for some years until I sealed the rim of plastic top of its cyclonic air / oil separator. The plastic warps and allows oil to spray on to the air filter element; this fixes it. Sounds like a big job but is quite easy.

Remove the air cleaner's cover as you would to change the air filter. Inside is what looks like a small "can" with a plastic top that has a hose connection to the valve cover. Its top is held in place by two metal tabs, gently bend one or both of these up until the plastic top can be removed. Note the top's orientation before lifting it out. Apply Permatex to the top's edges that meet the "can" inside the air cleaner. Replace the top in the correct orientation and bend the tabs so top is tight on its "can." Install a new air filter if the old one is badly oil soaked and close it up. Finished.

This will reduce the oily air filter problem by 98%.

I looked at the air cleaner compartment. The mix chamber is not inside but under the Air filter compartment. It's held down by three nuts. Naturally two of them are broken and that is what holds the air filter close to the intake chamber, letting I assume, more of the oil in. I believe there is blow by but not sure if that matters all that much, This car runs very nice at 80. Drove it all the way from Michigan to California going 80 almost all the way. So maybe I will find another shop to work on my car. Steve

put in a new air filter and drive it. if it rattles at idle get a bath towel put it on the top of the air cleaner and close the hood. worked for me on the noise issue.

case

the case, minus a few cans!

Case -- I like it! A pretty well-known MB guy up here in Wisconsin (the late Randy Durrance) suggested fitting an old shock absorber bushing between the air filter housing and the valve cover to reduce the vibration. The towel, though, is a much simpler, more common-sense approach.

The placement and stability of the air filter housing in an OM617 engine can be a big factor in oil leakage from the return line from the oil separator to the oil pan. It can also go a long way in preserving the air filter mount, which is a known weak spot on these cars. I have two W123s; one has a broken mount; the other has been welded.

. To quote Monty Burns and a legion of '70s stoners....excellent!

Russ Maki Ixonia, Wis.

when I first purchased my 240D with 85k km on it I also noticed an oily air filter. An independent mechanic garage told me that there was 'blow-by' and that a re and re of the engine was definitely, no choice, in order. My MB dealer told me to hold off and simply replace the filter more often. I sold the car to a taxi driver who used it as an taxi at 260k km. I guess, the point is, don't worry about blow-by and replace the air cleaner more often

regards

Talking about air cleaner mounts, I'm going to the dealership tomorrow to pick up some of the rubber mounts that hold the air cleaner housing to the bracket. One of them is broken again. At least this time the bracket is still in one piece. I concluded that the next time the bracket breaks, I'm going to have it welded with extra pieces of metal added to reinforce it.

Also, on the bracket, I noticed there are two sets of mounting holes for the rubber mounts. One set is slightly forward of the other set. When the last mechanic put the bracket in, which was new, he used the holes which position the air cleaner slightly back. Couple of years later, one of the mounts tore out of the bracket ruining the threads. So, I repositioned the mounts, using the forward set of holes. This seems to have worked better, as I've only lost one mount in the last 2 years and that was a rubber seperation, everything else is still ok. Not sure why the bracket has two set of holes, unless MB knows what a piece of crap it is so they give you the other set to use just in case :)