During the tear down for a 4100 rebuild I found that the two small brass tubes that are inside the two larger brass tubes on the primary venturi cluster have come loose from the venturi body. These two small tubes have a small bleed hole drilled in the side of each but only on one end. There is no clear indication of which end these small bleed holes should go into the body, up or down.

Any ideas?

and its a pain, put on your detective hat and look carefully at the ends to determine which side was pressed into the venturi, Check if both sides ar the same if they are (and in the couple of cases I have had this happen it was obvious which side was pressed or they could only go in one obvious way or it wouldn't matter.

Bill White
White Automotive

No indication that I can see. They are uniformly stained.

I have been told that they go in with the small bleed hole up into the venturi but I cant seem to get them to seat.