[tkv000]

I was perusing the mog manuals for information on how to service the firewall brake valve, as mine leaks out the bottom tube, I ran across this, thought it would be good info to share

Due to a machining fault at the supplier's, the air dryers may start to leak at the housing. The causes for this have now been identified and appropriate counter-measures have been introduced to remedy the fault.

The check should be made the next time the vehicle comes into the workshop or during the next maintenance service.

As of VIN 437.125 1W 197 136 these air dryers no longer leak. Stocks in the GLC and in the regional warehouses have been cleared of old parts.

This is old info (claims ended in 2002) but there may be some on the road still with the issue, something to check.

I've included the entire article for those interested.

 

[NeedforSpeed502]

Trev,

Let me know any info you find on the brake valve. Mine leaks out of the same spot and I am trying to see if I can take it apart and just clean it or if it needs more.

 

[TRUKTOR]

There is a rebuild kit for the firewall valve... " . Motorwagenbremseventil" or something.
I ordered one from Germany and the valve went back to normal and quit leaking, so I left
It alone. It was a bag with something like 22 different O-rings in it. I don't know if it covered different models, or it came with duplicates, but looking at the bag of O-rings, and the size of the housing on the fire wall, I'm not sure that even the Germans could cram that
Many O-Rings in there....

 

[BloodyGerman]

some people on UNIMURR had success with spraying WD40 thru the vent port into the brake valve while somebody else floored the brake pedal (with empty air tank I'd assume).

 

[tkv000]

Trev,

Let me know any info you find on the brake valve. Mine leaks out of the same spot and I am trying to see if I can take it apart and just clean it or if it needs more.

Well, that took a while. I couldn't find this anywhere but ran across it today (after I've already ordered a new firewall brake valve)

Here is, at the very least, an exploded diagram. Because as I found out, if you take it apart wrong, it will indeed, explode.