there are 2 inputs (one from the head, one from the block) and 2 exhausts (one back to the sump and one that carries on to the other tank) on the catch tank
this then has an inlet (from the catch tank) and an exhaust (vents to atmosphere)

the catch tank (the first one) has a plate inside so when the misty oil hits the plate from the 2 inlets the vapour condenses onto the plate and dribbles back down into the sump again

the second exhaust then lets any still misty oil go onto the second tank and this tank then catches any remaining oil

if there is STILL misty oil then this goes out the system somewhere else and vents to atmosphere so you only loose a bit of oil

at least that's the theory, if you have to vents in the scooby then you simply do the same thing, if you've got 3 then just join them up, it's not like you will cause a restriction is it











*some of the above might not be true, but i think it is