pitot static quick connect fitting issue

[erich weaver]

As part of a panel makeover, my partner and I are revamping the pitot static plumbing, repacing the bulky old bulky plastic fittings with the newer quick-connect fittings from SteinAir. Anticipated a straight-forward operation but not to be. None of the male fittings that screw in to the female fittings on the back of the EFIS, autopilot and backup airspeed indicator will thread correctly. They look like they will fit but apparently are just slightly off. I know 1/8 NPT threaded futtings are standard. The old plastic fittings work perfectly, and my 1/8NPT tap runs fine in the threads of the female fittings, so something is scewy with the male quick connect fittings. Anybody else have this issue? Bad batch? Frustrating...