When I manually change the recipe of an assembler then the fluid currently in the assembler tries to flow into any connected fluid boxes. So a fairly empty pipe or a tank connected to the assembler will preserve the fluid when the recipe is changed.
When I clear the recipe with the crafting combinator, calling
Code: Select all
assembler.set_recipe(nil)
But here comes the strange part: When I change the recipe with
Code: Select all
assembler.set_recipe("something else")