Brass fitting sealant for alcohol tanks?

[gordyzx9r]

On my original plastic float switch for my alcohol system there was some kind of sealant on the threads.  I was told I wouldn't need it since the new float switch was brass and I was hooking it up to a brass line.



Should I use some kind of sealant on the threads?  And if so, what kind?  When I went to Lowe's and asked for a brass fittings sealant they just looked at me like I was crazy.

[Steve Wood]

if the fittings are npt, they should not need any, but, if you wish to use something, I would choose one of the liquid teflon sealants

[gordyzx9r]

if the fittings are npt, they should not need any, but, if you wish to use something, I would choose one of the liquid teflon sealants

NPT?

[SuperSix]

if the fittings are npt, they should not need any, but, if you wish to use something, I would choose one of the liquid teflon sealants

NPT?

Normal Pipe thread, I think. A proper NPT connection shouldn't need sealant.

[Steve Wood]

NPT is a tapered, self sealing thread, but, a lot of this crap that is imported does not always seal without undue torque so a little sealant will aid in curing a potential problem

[daveismissing]

national pipe thread/national coarse thread/national fine thread

[earlbrown]

I thought it was National Pipe Tapered as opposed to National Pipe Straight.

[Steve Wood]

http://www.engineeringtoolbox.com/npt-national-pipe-taper-threads-d_750.html

Use sealant

[The Radius Kid]

Sealant would be a good idea.
You could get away without it,but there's always the chance........ ..
The primary purpose of thread sealant is not to seal,but to lubricate the threads so they engage deeper.
It's secondary purpose is to seal small gaps in the thread interface.
 
Read here:
 
http://tds.loctite.com/tds5/docs/567-EN.PDF