Good morning, Looking for the thread size of the tube nut that goes into the filter housing of the Quadrajet. Thanks. Robbie
Off the top of my head I do not know the exact thread size and pitch but I do know it takes a 5/8" line wrench and a 1" wrench to hold the filter housing while you tighten it.
5/8" - 18 tube nut. Typical for SAE 3/8" OEM fuel lines w/90° double flare, also known as inverted flare. And FYI the filter fitting thread into the carb itself is a lot more unusual, it's 1" - 20 UNEF (Unified National Extra Fine) thread. Devon