I think I am starting to understand that you are saying I have pre-polluted the fluid inside the thruster itself, then when I reconnect the fluid is able to move backwards, back into the pipes. I know you said this is by design, but I would argue that this post gaining such traction implies the syst...

I am experiencing the same issue as the OP. I have attached gif, version & save file for inspection. Platform is Zaxaramas. Cheers, Steve Sorry but your gif doesn't contain enough information to make it a bug. Like mentioned earlier the fluid inputs are not filtered to 1 type of fluid by design...

Have confirmed that as OP suggested, the bug seems to present itself when the inputs are parallel to eachother.

This configuration does not present the problem:

I am experiencing the same issue as the OP.

I have attached gif, version & save file for inspection. Platform is Zaxaramas.

Cheers,
Steve