This is the greatest stuff since chewing gum for sealing tiny leaks. It has the viscosity of water almost and will flow into the tiniest of gaps. The surface tension is such that it will coat vertical surfaces.

I would use an eye dropper to place a tiny amount of it around the tube and allow it to flow into the gap. It adheres like super glue but will tolerate temperatures up to 350 F.

http://www.mgchemicals.com/products/422a.html

I would not be a bit surprised if it improves the sealing if used in scratches on the wear surface of rotor housings with new apex seals. Try it in a car engine first. JB Weld may also work in this application. It sounds like it would burn off and Paul Lamar is insane but that is what some people said about welding p-ports. The actual temperature of the wear surface is a lot lower than most people think.

Paul Lamar