TOY4LEE

I just completed the OFH replacement from underneath the car. I needed a service anyway, so I drained the oil and coolant. I then removed the starter, disconnected a couple wires, disconnected wire loom clips from ribs on block and OFH, and removed the steering section between the column and rack. Removing the 5 housing bolts is pretty straight forward. The spring clamp on the coolant hose to the tube going to the head is turned up so I couldn't get plyers on it. I cut the hose at the tube and used my Dremel to cut the clamp off. Be careful on this part. I should have drained the block via the plug under the housing to avoid the antifreeze shower.
To reinstall I put the spring clamp from the original OFH on the tube with the plyers attached, then put the housing in place and started the hose onto the tube. Next, I started a couple of bolts to hold the housing still, put a zip tie on the plyers holding the clamp open, slid the clamp on the hose, and started the process of getting the hose in place. This was the hardest part of the job.
Now I have a message that the traction control system is unavailable see operators manual and the curse control doesn't work. I have done the lock to lock to reset it, checked the 2 connectors l disconnected, removed and repositioned the steering section that I removed to no avail. If anyone can shed some light on what I might have done I would appreciate it.
Thanks
Lee

CryptoJoe

Do you have the torque specs for the oil filter housing and the intake manifold by any chance?

antboii

This is what I used when I was doing mine. Couldn’t find it for our cars specifically either.. 20Nm - 14.75ftlbs - “just tight enough” You don’t want to crack the housing. Tighten evenly and torque in a sequence.

CryptoJoe

Sweet. Thanks a lot. What about for the intake manifold?

CryptoJoe

I reached out to Mercedes and they said the torque spec for the oil filter housing is 20 Nm and the intake manifold to head is 14 Nm. Thanks to everyone that helped. Car is working fine.

antboii

Awesome man, thanks for reaching out and confirming for all of us! Glad to hear you got the job wrapped up.

Ant

thegolffather

How much would a shop charge for labor to do this? is this a common issue with the C250 mine seems to have an oil leak. The car is new to me so I am getting to know her...

antboii

I'm not sure what a shop would charge but it wouldn't be less than $1k. It's a pretty labor intensive job (not hard) but it takes time.

Intake manifold needs to be removed as well as the starter. Then you'll have all the access to swap out the oil filter housing.

Yes, it seems to be a common issue with our cars (and others) the gasket goes bad eventually.

I would also do the oil cap test to see if you have a clogged/stuck PCV system. That will exaggerate the oil leaks.

Happy to help if you have more questions.

Ant

CryptoJoe

Ant is correct here. It will at least be 1K. This helped me a lot though. It's not the best but it helped. This helped with the intake manifold removal only. You will need to remove the intake / air filter housing. Then remove the intake manifold. Then the starter. Then a small fuel line and then you will need to remove the hose that is attached to the oil filter housing. I recommend purchasing the OE OFH because it will come with a new hose. There is this really annoying o-ring that you will have to remove and replace. It's very difficult to get it back on so I just replaced it with a basic one from Autozone that tightens with a screw driver. The manifold and the OFH will need to tightened down to the specs bc if it's too tight then the plastic will crack or too loose you will continue to have a leak.

It is doable though. You can rent the torque wrench from Autozone. You will need a new gasket for the manifold of course.

thegolffather

Thanks, What is an oil cap test?

antboii

Hey, the oil cap test is similar to checking blow by on a diesel.

With the car running and in park, undo the oil cap and place it over the oil fill hole.

If the oil cap bobbles and jumps all over the place, you are experiencing blow bye/excessive crankcase pressure.

The oil cap SHOULD be sucked in by the vacuum of the engine running.

If it is jumping all over and you can feel excessive crankcase pressure your PCV system is likely clogged.

There are a few different threads on that from myself and others on the forum.

Ant

meazz1

Another challenge I faced was to remove the clamp from the pipe to the OFH hose. With the right pliers or clamp removal tool it's easy.