I wondered why the previous owner had smeared oodles of RTV around the smoke pipe outlet on my Severn coal boiler. As I removed the RTV it became obvious that pieces were cracked, broken and missing where the 8" smoke cast iron smoke pipe assembly connects to the boiler. Some of the mounting studs are either broken or missing. Here is a pic of what I'm left with...http://img153.imageshack.us/img153/9269/0lp7.jpg
The piece in the upper left corner will be removed when I can get the nut that holds it freed up.
As you can see I'm left with an irregular opening and nothing really there to attach to.
The chimney flue opening is 7" and the chimney is 16" from the back of the boiler.
My first thought is to use something like this in the opening to transition to a 6" round pipe and use cement to fill any leftover gaps:
This link is broken, either the page no longer exists or there is some other issue like a typo.
What do you think? Any thoughts or suggestions?