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

Hi Rob, I will be seeing you at Cabin Fever and I look forward to that.
Unfortunately I am not the right person to fix your boiler. 

If it were me I would get a new boiler. 
Ministeam has them as does Matthias Brenner (station500 on eBay)

https://www.ministeam.com/products/wilesco-01662?_pos=1&_psq=boiler+wilesco+d409&_ss=e&_v=1.0

If you are set on a repair you should show it to Bruce (St Paul Steam) 
He will be at Cabin Fever somewhere near me. He may be able to help.

Gil