Vent line questions

[XchaosX]

Should my air pack vent line be capped like this?

My front axle vent also has a cap like it on it

My slobber tube has two holes in it, the bottom hole I believe has the gas tank vent line tied into it if I traced the right line. What should be attached to the top hole?

 

[M35A2-AZ]

The little caps are vents that are used on the axles and other things.
You need to check them from time to time to make sure they do not plug up.

 

[jamawieb]

Looks right to me. The caps protect the vent from dirt. I'm not sure what the second hole is for, but it would be some sort of vent tubing. I think they are usually plugged.