Originally Posted by
zip439
As you said you remove it from the car at oil change intervals and drain the can from the bottom. There is a cap there that unscrews. I put a small o-ring inside the cap to help make a good seal and when I drain the can I will spray brake or carb cleaner into it to help it drain and clean the inside. Be very careful with the mounting screws; Dropping is a one time thing because they disappear down a bottomless hole.
I put a couple of paper towels under mine. This way if I drop the nut or washer, it lands on the paper towel.
The new catch cans from Needswings has the O-ring in them now.
Thanks for the tip about spraying the inside to help the oil out.