Just purchased a 4 way manifold. Crimped everything and checked for leaks and all of the ball valve barb fittings leaked. So I took them apart they had thread sealant on them. I tired teflon tape but I don’t think they are actually pipe thread. I’ve used blue loctite before for other applications but would it work for pressure? I ended up over tightening on and broke one valve already.
Use loctite 565. We use it on our air valves at my work and its incredible. Let it set up for 24 hours
As I watch some plumbers put stuff together, they will use the tape and liquid sealant stuff. Sneezles61
Tephlon tape and pipe dope what I leat for gas. But that was black pipe. On those fittings tephlon should do it. If it leaks probably need more wraps