Teflon tape for raw water intake

[shantijwk]

Is OK to use Teflon tape on the thru hull threads for the raw water intake? I removed an old gate valve and will replace it with a ball valve tomorrow. I have an O’Day 27 with a Universal Atomic diesel. The old valve looked like it had Permatex on the threads [black gack]. I believe that Permatex is/was a polysulfide type product. If so could I just use Boat Life Caulk on the threads? Thoughts and experience greatly appreciated.
Wayne

[trantor12020]

Teflon tape is prefectly alright to contain process fluid of <10barg and temp <100degC at where I work. However, qulaity of the NPT thread plays an important part there. I don't think your thru' hull fittings are of enough quality that you can rely on/just teflon tape. Remember thru hulls are usually fit and forget. So you want to be sure it will not be a problem.

[Goodnewsboy]

Be careful with teflon tape on suction connections. Stray bits of tape can do bad things to some pumps. I'd use teflon paste applied carefully to the threads only.