Help me figure out what this part is...
 

Their is a line running off the vacuum valve to a bolt. From the bolt their is another line that runs to something but I'm not sure what that is. It's the thing that has the shiny metal "hose" that fits to it. Anyway, it's the bolt I'm trying to figure out that I need. It's got two spots for lines and there is a rubber connector that fits the lines to the bolt. The rubber was all eaten up and when I tried puling them out, one of the little connections on the bolt just snapped off. I think it's one of these:
http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&year=1984&make=MB&model=300-DT-001&category=All&part=Thermo+Vacuum+Valve&appEngines=_any
They have a part called blue and one called black. What's up with that? An how about the rubber connectors, I'll need those too. Is it these:
http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&year=1984&make=MB&model=300-DT-001&category=D&part=Diesel+Inj.+Plug
I sort of doubt it but can't find anything that looks similar. Thanks for the help!

Oh and the bolt says carb on it.

Without having any idea what vehicle or engine you are dealing with, I would guess that you are talking about an EGR valve. The "bolt" is actually a thermal switch which prevents vacuum from being routed to the EGR valve when the engine is cold.

Before buying EGR parts, you might want to consider the merits of having the EGR sytem in the first place.

Ok first things first. Is this a diesel or a gasser? What model car/engine?

A shiny metal tube sounds like an EGR valve which you do not need connected.

1984 300d.

I think it is the EGR valve. But it's the bolt that has two line connections on it that is busted. No way to connect those two lines without a new one. What does it do? Can I run the car without this hooked up?

If you cap the line that is not connected to the EGR valve, you will eliminate the vacuum leak and could use the car with no negative side effects.

Can you take a picture?

I wish...

Well what's the pint of the lines? And what part do I need to buy to replace that bolt?

wow! I got my camera working
here's a pic

Plug the vacuum lines coming from the black box, you don't need or want them.

So it looks like one line is connected to the bolt but actualy the rubber connector fiting is all craked and has air leaks. So what part is it and what does it all mean?

Why don't I want them? What do they do??? I can't imagine why it's there if you don't want or need it?

It is for the EGR, the EGR is a complete waste of metal and does nothing good for the engine.