Wing fuel tank leaks at fuel pickup

Both wing tanks on my 415C developed a seep from the aluminum fitting that attaches to the fuel line at the bottom of the tank. This fitting also holds the tank drain valve and the finger screen. The fittings had aluminum crush washers at both ends and that's where the fuel is seeping out. Are those crush washers correct? Part number? There was a ProSeal-like sealant around the fittings. Is there supposed to be sealant there? In short, how do you install the pickup fittings so they don't leak?
Thanks