Catch Can Routing....

[TheBandit]

The hissing is a vacuum leak indicating the drain is not closed off. The image seems to show just a hose barb with no sort of drain valve / petcock valve. You will need to either cap that during normal use or replace it with a petcock valve so it can be kept closed until you are ready to drain it.

[69camarokid]

The hissing is a vacuum leak indicating the drain is not closed off. The image seems to show just a hose barb with no sort of drain valve / petcock valve. You will need to either cap that during normal use or replace it with a petcock valve so it can be kept closed until you are ready to drain it.

I am a fool. I didnt pay enough attention to the pic I posted. My can has the petcock style valve on the bottom, not a hose barb.

What I found is that if when the petcock valve its opposite of what you think it should be. If you spin it til its tight, it is actually open. When you spin it til its as loose as possible, the valve is actually closed. screwing it completely in the opposite direction took care of my hissing noise! Yah!