filling catch can?

umm the catch can is supposed to cycle... that kinda the point lol

the radiator gets hot so the fluid expands.. then the now extra fluid gets pushed into the overflow...

when i cools it will suck it back in...

when you put a high cap on it it has to reach that pressure before it can vent...

your suposed to fill the overflow half way cold and then just let it do its thing...

helps get rid of air also...