Hello guys. I'm in the process of putting throttle body injection on my 1973 Mercedes 280.







Now you can see in these two pictures theirs that nipple with coolant in it... basically I'm hoping you guys could tell me if I can just cap that off and what it does? the way I'm setting up my efi puts the throttle right in that spot so I can't have a hose in the way.


Thanks.

also can anyone explain what that tube does? can it be deleted? It's hard to find information about these engines in my experience... or maybe I just don't know how to google good enough.

DB:

If there is a part in your pictures that you think contains coolant, please mark it.

If you are referring to the pipe that is between the carb flange and the cam box, it is EGR.
The vertical rubber connector between the manifold and the cam box is crankcase ventilation.

Hey thanks for the quick response.




The hose circled in orange is the hose that connects to the coolant nipple filled with coolant

Also do you happen to know what that red hose is connected to on the intake manifold? that red hose is also filled with coolant.

This is the coolant nipple I'm talking about that's in the way. It either needs to be plugged, if possible or re routed.

DB:

The nipple hiding behind the EGR pipe can be deleted; it is a screwed-in steel fitting.
It was used to supply hot water to the choke; the hose marked in orange was the exit water connection from the choke, and may also be deleted.

The red hose connected to the manifold under the carb flange is the exit of water that heats the floor of the manifold under the throttles. It should be retained.

Thanks for the information! 1 step closer to having my TBI now!!