[Stijn_Thys]

Dear All,

I am new to the forum. As I was looking on the net for a problem we have on our old Mercedes truck I stumbled upon this form and really hope that some members with technical experience can help me...

Altough it is about the brake system of the Mercedes 1013 1980 this was the closest forum I could post to.

The question is concerning the following:

We have air escaping in the middle vent seen on the picture. This is according to the local truck inspection not allowed. (if we park the truck with the engine of it looses pressure rather quickly on the brake system).
How can this be solved? or what is the problem on this?

Hope someone can help...
thanks to all...

 

[Dreadnought]

I don,t pretend to be a qualified mechanic, but when I ran trucks years ago, if something like this happened, the first thing I would do is take off the valve and clean it thoroughly, 9 times out of 10 that cured it, it was just a piece of dirt holding the valve open. If it doesn,t work, buy new valve (or get one from a truck dismantler and fit, it looks like a bolt on job. (Make sure you have the correct valve though! some may look the same but operate at different pressures.) Good Luck.

 

[Stijn_Thys]

Thank you for the speedy reply...
I was doubting of what kind of part it exactly was. I thought it was some kind of vent. But you suggest it is some kind of pressure valve?
Is it easy to get off, or should I get the entire unit off (or is this too complicated?)

Thanks

 

[Dreadnought]

Think Truck mechanic? are they highly educated? No so you should not have much trouble taking off the valve or the entire unit to clean it. Alcohol is good for cleaning this type of equipment and valves. Make sure that if you do take the unit apart you do it in a clean space on a bench that is clean. It may be that a spring inside the valve has weakened with use and is no longer pushing against a diaphragm, maybe you can just stretch the spring or replace just the spring. Again Good Luck....(fixing it yourself feels a lot better than paying some mechanic to do it).

 

[gordon123]

It's hard to tell from the photo what the unit is meant to be, but what I'd suggest is cleaning it all over and looking for a part number.

Since its a Mercedes machine I'd guess that it's made by Bosch. Then either search on Google or contact your local truck factor/Bosch agent with the part number who will tell you if there's a repair kit available.

It sounds like the same kind of problem that the air assist chamber on U900/U1100s get.

Cheers,

Gordon

 

[esde]

Does that truck have air brakes, or air over hydraulic? Where in the system is that box; what operates it and where do the lines we see go? I agree that something needs either adjustment, cleaning, or rebuilding. Sometimes adjusting and cleaning can prolong the time before rebuilding (but not always).