I inherited my late great uncles 3" scale Suffolk dredging tractor. When I looked at it the engine had seized and needed much loved tlc. I was checking the boiler and fixings and the safety valve wasn't tight. So I extracted it checked the thread and condition and I think it has been crossed threaded. I don't have any plans or information on the boiler and fixings and don't know if or how to get parts or if I have to replace boiler of just safety valve. If anyone can help it would be greatly appreciated. Thanks in advance. Tristan