IGB

These are standard threaded screws. Counter clockwise to loosen them.

Of course, since it is likely that you are looking at it from the opposite direction (you facing towards the rear of the car), your wrench/ratchet or whatever tool is going to spin clockwise to loosen.

The torque spec for that bolt is 12 N.m = 8.85 ft.lbs... So it really doesn't require much force to get them off past that tight range. Since different metals will expand to differing degrees with heat, if you've tried to loosen them while the engine is cold, try it again while it is a bit warm, and vice versa.

If you still need to borrow tools, PM me with your contact number. I cannot promise anything for today (possible, but not for sure), but by Thursday at the latest, I can meet up with you and I'll bring my tools.

Just an FYI, I could not find my separate T-30 Torx bit, and in spite of my saying a socket Torx bit would not work with a ratchet (too think for that tight space) I figured you can use the T-30 socket, along with the ratcheting 1/4 wrench in the following manner:

This is what they look like separated...



And...

This is how you'd use them together.



The depth might still be an issue for the one screw farthest towards the left of the engine, so I will look some more for my separate T-30 Torx bit, just in case.

Let me know...

cahido123

I'm new with mb, and was thinking that I had a very big trouble but with this post I will be very very relaxed and the next monday will be finding the spare parts

ERA

Hi !
I know that this is an old post, but I would like to ask you something. If you are changing the expansion plugs, you need to drain the engine oil ? I think I just need a cold engine.
The second question is, do I need to put some oil on the expansion plug to have a better seating ?

Thanks

gamma300C

No, no need to drain oil. When I changed mine (09 C300), I cleaned the area after popping the old plugs with brake cleaner(any solvent will do) and spread a thin, even layer of hi temp RTV silicone sealant on the new plug edges where they seat. Snap in easily, wipe off excess sealant if any, and still good 2 years later.

ERA

Thanks for your help ! I just chance the plugs (small ones). I can't find the Big one hahaha

Brian McL

I have a BAD leak from that vacuum pump and it looks almost impossible to remove....no room. Is there a DIY on replacing the "O" ring? Thanks

NewShockerGuy

I think this is my issue and I'm glad I found this thread.

I haven't had a huge amount of time to look other than when I saw a small oil mark on my garage floor from having our 09' w211 on the lift for several days. But then when I started the car I kept smelling an odd smell.

When I finally looked yesterday I see that there is oil residue when I placed my hand in the back passenger engine bay at below the black disc item, which I can only assume is the pump from this picture.



But I haven't verified yet on the other plugs. I did see however there was oil on the o2 sensor exterior plug and thus more than likely hitting the hot exhaust causing the smell...
But it does look super tight to be able to work on it...


EDIT: 12-12-2022
I bought the entire parts from FCP Euro. 3 caps, and the breather with 4 new bolts. I think it came to about $100. VERY easy to change. I just popped off the old plastic caps on the back of the engine. They were brittle but weren't leaking. Then went over to the breather piece. ALL bolts were loose. So, I imagine that's why it was leaking for me. however, the inside diaphragm piece was much larger than the newer piece, so I imagine that was worn out. This time around I used blue loctite for the 4 bolts so they wouldn't back out and get loose over time. The hardest part for me was getting the air inlet hoses off the manifold/intake. They are such a stupid/stiff design it makes for an annoyance when removing and putting them back on. I'll check in a few days to see if there are any oil spots/leaks but I'm glad this was a cheaper fix and quite a DIY/easy thing to do. I was fearing prior to finding this thread that it was gonna be $$$$.


-Nigel