Which parts allow fuel crossfeed and which do not?

[NutellaonToast]

Title says it all: Which parts allow fuel crossfeed and which do not?  I have tried a fair amount of googling and can't find a definitive list.  Thanks!

[bewing]

Welcome to the forums.

Everything except heatshields and I-Beams allow crossfeed, AFAIK.

Edited March 12, 2019 by bewing

[HvP]

Hello @NutellaonToast welcome to the KSP forums!

Very few stock parts completely block fuel crossfeed, and those will have orange text in the part description which says "No Fuel Crossfeed." Those are: the M-series structural panels and I-beams; the SP-series structural panels from the Making History expansion; and all of the heat shields. The launch stability enhancer technically cannot transfer to other parts, although it is rarely an issue.

Some parts will block crossfeed by default, but you have the option to toggle crossfeed on individual parts from the right-click part action window. These parts have orange text in the part description which says, "Crossfeed toggles in Editor and Flight. Default Off." Those include: every decoupler and separator, both radially attached and stack node attached decouplers, including the small hardpoint and structural pylon. This does not include the engine plates from the Making History expansion since they always allow crossfeed.

All of the docking ports have crossfeed turned on by default, but this can be toggled off in the right-click part action menu.

Everything else will always allow crossfeed.

Edited March 12, 2019 by HvP

[NutellaonToast]

Thanks both so much for answering my question!