When I installed the Mightymouse C5/C6 mild kit a few months ago, I used their 3/8" rubber hose between the can and the intake & valley cover nipple. A few weeks ago I changed the length of the hose between the can and the valley nipple for a cleaner install, but in trying to slide the hose off the nipple, the entire nipple pulled off the cover; I had to cut the hose to remove it from the nipple. When I recently went to drain the can, I disconnected the line from the can that goes to the valley cover. Barely fiddling hose caused the metal nipple to pull out of the valley cover. It goes back in easily, but do I need to make a better seal with that nipple and/or replace the entire valley cover? Once the nipple is secure/sealed again, should I use some sort of lubricant between that nipple and the hose?

 

You can probably just rough up the nipple and the hole, and use epoxy on it.

Try silicone dielectric grease on the hose.