Gasoline thread sealant can be used on all except:

In the context of vapor recovery systems, it is critical to use appropriate sealants that are compatible with the various components involved, particularly those that come into contact with fuels or vapors. Gasoline thread sealants are formulated to prevent leaks in fuel applications by providing a seal that can withstand the harsh conditions associated with gasoline.

The threaded portion of rotatable adaptors is designed to allow for movement and rotation in the connection, and using a thread sealant in this area could inhibit the intended function of the adaptor by creating a rigid bond between the threads. It is essential that these adaptors maintain their ability to rotate and function correctly to facilitate the effective recovery of vapor. Therefore, the use of gasoline thread sealant in this application is not recommended.

In contrast, the other components like the P/V valve, ball float, and riser adaptor are often stationary parts that require a secure seal to prevent leaks. These components benefit from the use of gasoline thread sealant to ensure that any connections are leak-proof, thus maintaining system integrity and performance.