"Aviation Sealer" is a brush-on liquid that's sort of a poop-brown color, and it has very little "sticky" properties. High Tack is more of a glue than a sealer, designed to stick a gasket into place while the part is being positioned. I prefer a variation of aviation sealer called Permatex Super 300, which is almost black, and seals much better than 3-D, which is the regular aviation brush-on sealer. Super 300 was developed to seal aircraft fuel system parts exposed to 115/145 octane aviation gasoline, and it's remarkable stuff! I use it on steel shim head gaskets on race engines, not to seal compression, but to prevent hot coolant from seeping into places it doesn't belong. At oil pan corners where side gaskets meet front and rear pan seals, I like to use a dab of RTV to bridge the joint and prevent oil seeps. Ditto on small block V-8 intake manifold corners.
Jerry
Last edited by Hotrod Lincoln; 03/19/2008 3:48 AM.
