It skins over quite rapidly, so assemble the parts immediately. Unlike solvent-based substances such as shellac, they cure when deprived of air inside an engine joint rather than when exposed to air. Only a thin film will work, so anaerobics may only be used on rigid castings with machined flanges, not on flexible stampings. All it's capable of filling in are tool marks and pores. The cleanliness of the surfaces to be sealed is especially critical with this class of chemical.
Some types even come with a primer.
Apply a thin bead, but you don't have to rush assembly because anaerobics won't harden until sealed inside the seam. Back to top Hylomar is a sophisticated sealer long used in jet aircraft and missiles. But, like anaerobics, it's not intended to fill large gaps, so isn't suitable as a gasket substitute on steel stampings. It works well, however, on castings, and also makes a good supplement for coating gaskets and keeping them in place. Since it remains resilient, it helps seal old gaskets that must be reused in an emergency.