Since I have had this 2013 E550, I have had do do very little for maintenance other than regular oil services, tires, and a complete replacement of the rear subframe (under warranty).
These past few weeks I have replaced all of the turbo feed/ return lines, water pump and thermostat/housing.
The turbo lines and pump were not that big a deal considering I have all the weird tools and a limber 50 year old frame. Here's a couple things I learned during that whole process.
1. Do not forget the drivers side turbo feed hold down bolt...or you will be doing this job again in very short order. The serpentine belt wore a whole right through it. Fastened, it is about 1/4" away from the belt. Lesson learned.
2. After doing this a second time, I culled it down to a 1.5 hour job. No need to remove the fan, radiator hold down, radiator hoses. Just bleed a little....its good for you.
3. I decided to remove the "oil diversion" solenoid just below the thermostat housing to make the water pump job a bit easier. This "solenoid" can only be reattached to the block 1 way. What I did not notice upon removal is if there was a crush ring between it and the block. Im guessing there was some type of gasket there, as upon start up oil shot out of the block like you had 6 cups of coffee and had to pee while on your 4th hour of waiting in line at the dmv. Initially I could not tell exactly how or why this was happening. Mainly because I had to start the car, run to the engine, run back to the cab and shut it off. A comedy of confusion. The solenoid remained unplugged while all of this was happening. I called in a friend to start the car while I tried to figure out what was going on. This time I plugged it back in. He started it, no spray. Now totally confused. I found a crush washer and decided I know better than mercedes engineers and installed it. No leak, plugged in or not. The solenoid appears to have an area milled out for a crush washer. As with most small things that are subject to gravity in the engine bay of a modern mercedes, I have no idea where several bolts and possibly an old crush washer are. I have a feeling the next time I test a rumble strip on the highway, a virtual smorgasbord of used mercedes fasteners will pepper the travelers behind. At least 007 had a button....I will leave it to chance.

If there's a question culminating from this epic tale, i think it would be the following.

Have any of you had an issue with this darn oil diversion solenoid?

Thanks for the read. I've been here for a while, started a new account because my car has been keeping me way to busy with curve ***** to try and figure out my old user/password stuff.

Dan

 

Can you get a picture of it or a parts diagram would help. I am not sure what you're refering to.

In any case, good deal on maintenance well done!

 

This lil guy

This lil guy.

 

this looks like an oil pressure sensor... very few engines have one

Mercedes sensors in contact with super-heated oil develop oil leaks into harness.... down into Lambda contamination for ECU Misfire codes.

The question is how far into your engine harmess oil has progressed??

 

No clue, but i have no evidence as of yet of oil intrusion. This particular issue was self inflicted. The only codes this car has ever thrown at me is "thermostat below operating threshold " and " cam position sensor below threshold"...in 6 years. I replace parts post haste.

Shes been very good to me, and in return.

 

Do you see any electrical connection to the black part of that unit?

 

Yup. It's shielded, but the first inch is exposed insulated wire. It runs up through the intake where it terminates into the ecu harness. Last time i disconnected the harness to do a deep clean it was completely dry. (About 3 months ago)

 

Yeah I have that same bugger on my ‘14 E550 m278 coupe. It was hard to find that part number, and I believe I posted in here last year about it…and it’s copper washer(s). There are a couple of washers involved iirc…it’s a weird setup. As CB says, it’s apparently hella rare to have one too, so few have had the unique pleasure

 

That long through-bolt is ported, and as I found out the hard way…quite susceptible to any torque beyond a gentle nudge. I had to buy it twice

 

Thank you for the confirmation on the crush washers.
When you say "hella rare" , does that mean its rare to have that particular part....or oil pressure at 163k miles

 

Hahaha…both? Jk, rare part for sure. Most everyone just has the ‘plug’ in that location…which of course is also a source of leaks

 

Very interesting.