Should I drain the oil before replacing flame trap?

 

and were is this thing?

 

On top right in front of the fuel injector closest to the firewall. Has three hose connections. Big hose on top, little hose on the side and a medium hose on the bottom. Take off the little side hose first since the fitting breaks off easily. Then pull out of the bottom hose and top hose. Clean or replace.
You don't need to drain oil to replace it.

 

Besides the flame trap, you should also do the oil separator-that gets plugged up and is the problem besides the trap...