By thread sealant I mean teflon tape or joint sealing paste. You don't really want to put Loctite on those fittings, since you do want to be able to get them apart at some point. Also, you don't want to put anything on the line to Earl's fitting connections, since they are supposed to be self-sealing. Fittings like the NPT thread on the turbo, etc, should have some teflon tape or paste on them.