Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

  Just found out there is a JB Weld Ultimate Grey sealant that is said
to be good at high temps.  This is probably a better choice than the
black.  when I discovered it, the black was all I saw - and it works.
I suspect the grey would increase your confidence.  I'll probably
buy a tube of grey for good luck and use it next time I do one of
these 'Continental' sight glass rehabs.

Remember, on all surfaces to be sealed, cleanliness counts! 

Good Luck,
Wayne