You might want to consider using an
oil grade pipe sealant rather than RTV or teflon. I use a thread sealant that is used for natural gas, propane,
oil, diesel and gas applications. It does not harden and forms a tight seal in the threads. I have found that Teflon can leak and if you retighten something with RTV you can break it loose after it has hardened. A good pipe sealant will form a lasting seal and since it does not harden, if you tighten the bolt further, it still adheres to the threads.