Pipe threads are tapered, the design is supposed to get tighter and seal better as you thread it farther into the fitting, some type of sealer is usually needed unless the fittings are brass. Brass is soft and the threads will form pretty well and if the joint is low pressure you may not need sealer. IF the fittings are not pipe thread, such as a flare or inverted flare, the threads do not have any sealing ability, it is the face of the flared pipe against the flare seat that seals. I have used teflon tape sparingly on auto pipe threads, I also have used a gasket sealer such as Permatex Motoseal sparingly on difficult leakes. If your fittings are pipe thread then teflon tape should take care of it, If the joint is in good condition, normal white tape should work, it is thin and fills the microscopic voids in the threads. If the threads in the tank are good, you may have to use a new fitting so you aren't working with worn-out deformed threads on that half of the joint.
Last edited by 78buckshot; 11/07/2023 5:23 PM.
