The Master Airscrew filters are known for leaking / sucking air at the 2 piece body seam.   Pretty much everybody that uses them seals the body with CA or epoxy.  Best to do it when new, before you get fuel/oil in them.  I like them because of the small size.  No other issues once you get them sealed.

I use the MA filters for almost everything. I put a piece of heat shrink tubing over them, it seals the seam and the little shrink over the end holds them together.