Fixing the Downward Steam Problem
A previous post questioned why the safety valve steam didn't exhaust up through the safety valve holes. 'David & Val' recommended the solution. The holes on the safety valve cap on some A3's do not align with the valve holes on the top of the boiler. In fact, they were way off. Placing a drill through the top and spotting on the cap proved the problem was real. As you can see from the photo, the new holes need to be near to the centre and the other one was right on the edge of the cap (see pointer) and would be hidden by the flexible shroud. So I only used the centre hole drilling it a little larger than the originals. The original holes have been blocked off with 10BA screws, held in by Loctite and cut off. I now have my Flying Scotsman blowing off correctly!! I'll be looking at the other A3's too.
Hi Jan. your post regarding the A3 safety valve cover is of interest. Over the years, in addition to your observation, I have discovered the lack of alignment is often that the safety valve steam outlet has been knocked out of line following a LiveSteam accident...