Leaking inlet nut

[tucsonjwt]

I have a leaking inlet nut on my 83 C20 454 Quadrajet. I replaced the white nylon washer but it is still leaking. I think the problem is that the washer does not extend past the end of the inlet nut - I can feel the end of the inlet nut threads when I run my fingernail across the end of the nut with the new washer installed. Where can I get the correct washer and shouldn't it extend past the end of the inlet nut threads?

[tucsonjwt]

Answering my own question, the nylon washer on the bottom of the inlet nut (a.k.a. filter housing) should not be flush or extend past the bottom of the filter housing threads. There is a large enough hole in the mating area of the carburetor to allow for the threads of the filter housing to clear the edges of the mounting area and the nylon washer seats on the very narrow edges of the mating surface area.

I discovered that the filter housing threads, mating threads on the carburetor, hard line fitting and mating threads on the filter housing, all had a very fine residue of teflon tape from previous work on the carburetor. I used a fine wire brush to clean what threads I could reach, and then sprayed all threads with carburetor cleaner and wiped off these surfaces.

The primary problem was that the excessive teflon residue on the hard line fitting threads prevented the fitting from threading into the filter housing all the way, resulting in a leak.